Impact of Islamic Finance on the Great Moderation- How it affects volatility of the business cycle
Transcript of Impact of Islamic Finance on the Great Moderation- How it affects volatility of the business cycle
Student no: 620029286 1
Impact of Islamic Finance
on the Great Moderation:
how it affects volatility of
the business cycle.
Submitted by Prashina Gobind Samtani to the University of Exeter as a dissertation
for the Master of Science (MSc) in Economics September 2013
I certify that all material in this dissertation, which is not my own work has been
identified and that no material is included for which, a degree has previously been
conferred upon me.
Prashina Gobind Samtani
Student no: 620029286 2
Acknowledgements:
This dissertation “Impact of Islamic Finance on the Great Moderation: how it affects
volatility of the business cycle” is intended to serve the purpose of the authors’ final
term research paper in her postgraduate degree in the field of Economics.
Firstly, I would like to express my heartfelt gratitude to my supervisor Dr. Dudley
Cooke for his support and guidance throughout the journey of my research. His belief
has not only enabled me to discover this challenging area of economics but also
developed a better understanding of the econometric methods required to tackle this
challenge.
I am also thankful to my economics classmates, who not only have been able to boost
me whenever I was striving towards my goal but they also ease me with some
suggestions to move forward.
Last, but not least, to my parents, my sister and my nephew, who have been my utmost
inspiration and the pillars to keep me going till completion. I am most grateful to the
Lord Almighty for making all these possible.
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Abstract:
The Niche Islamic Finance has been growing considerably in the recent years. It is
useful to study the impact of this growth on the business cycle. GDP volatility is the
best proxy for the fluctuations that alter the business cycle. The Great Moderation
period coincides with the boost on the growth of Islamic Finance. The paper will
therefore model the relation between the two events. The emphasis would be on the
different banking systems affecting the low volatility of the business cycle that marks
the concept of Great Moderation. Panel regressions across 116 sample countries are
then run to experiment the hypothesis proposed. The panel was sub-divided to test
whether the percentage of Islamic Banking system in the country has an impact on the
volatility tested.
The results indicated that the presence of Islamic Banking systems contribute
significantly in explaining the low volatility during the period of interest. However, the
percentage of concentration of Islamic Banking system in each country does not
significantly explain this phenomenon.
Keywords: Islamic Finance, Business Cycle, Great Moderation, GDP volatility and
Panel regressions.
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List of Contents:
1. Introduction Page 6
1.1 Concept Page 6
1.2 Background History Page 6
1.3 Significance Page 9
2. Literature Review Page 9
3. Research Design Page 15
3.1 Sample Data Description Page 15
3.2 Dependent Variable Page 15
3.3 Independent Variables Page 15
3.3.1 Oil Volatility Page 15
3.3.2 Islamic Finance Dummy Page 16
3.3.3 Developing country Dummy Page 16
3.3.4 Investment Page 19
3.3.5 Inflation Volatility Page 19
3.3.6 Real Interest Rate Page 19
3.3.7 Credit Page 19
3.3.8 Trade Openness Page 19
3.3.9 Islamic banking concentration Page 20
4. Statistical Methodology Page 20
4.1 Panel Regression Page 20
4.1.1 Cross correlation between the variables Page 21
4.1.2 Descriptive Statistics Page 22
4.1.3 Variance Inflation Factor test Page 23
4.2 Sub-panel regression Page 23
4.3 Method of Estimation Page 27
5. Results Page 31
5.1 Panel Regression Page 31
5.2 Sub-panel Regression Page 33
5.3 Panel Validity Tests Page 34
6. Discussion Page 41
7. Limitations and Further Research Page 43
8. Conclusion Page 45
9. Appendices Page 46
10. Glossary Page 50
11. References Page 51
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List of Figures and Tables:
Table 1- Major Differences between Islamic & Conventional Banking System. ............... 8
Table 2 - Summary of Literature Review and Usefulness to the Research ..................... 14
Table 3 - Relation between Developing Dummy and Islamic Finance Dummy ............... 18
Table 4- Sub-division of main regression panel ................................................................ 21
Table 5- Correlation matrix of Regression variables ........................................................ 22
Table 6- Description statistics of Regression Variables .................................................... 23
Table 7- Variance Inflation Factor test ............................................................................. 23
Table 8- Sub-division of sub-panel regression ................................................................... 26
Table 9- Computation of transformation parameter in Random Effects Model .............. 29
Table 10- Hausman test ..................................................................................................... 30
Table 11- Panel Regression results .................................................................................... 31
Table 12- Sub-panel Regression results ............................................................................ 33
Table 13- Model Selection test A ........................................................................................ 36
Table 14- Model Selection test B ........................................................................................ 37
Table 15- Serial Correlation validity tests ........................................................................ 38
Table 16- Heteroskedasticity validity test ......................................................................... 39
Table 17- Transformed final model robust to heteroskedasticity and correlation ........... 40
Figure 1-Period of Great Moderation presented by Annual GDP growth over time ......... 6
Figure 2-Diffusion timeline of Islamic Banking System ..................................................... 7
Figure 3- Phase Diagram of Investment............................................................................ 12
Figure 4-Changes of Oil Volatility over time ..................................................................... 16
Figure 5- Number of Islamic Banks across the Globe ....................................................... 25
Figure 6- Volatility of 89 countries over time………………………………………………….26
Figure 7- Volatility of 23 countries over time………………………………………………….26
Figure 8- Flowchart of tests to select appropriate method of estimation………………….35
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1. Introduction
1.1 Concept
Great Moderation is a concept that arises around 1985 when the periods of low
volatility in the business cycle begun. Many empirical literatures have investigated the
occurrence of this pattern. Gradually, the Great Moderation lost its publicity due to the
occurrence of financial bubble crisis and most of the research shifted towards this area.
It is of no surprise that Financial Intermediaries play a key role in economic growth as
stated by the report in IMF (2000, p.164). Coincidently, a niche finance market known
as Islamic finance started growing in the US and European region around the same
period. The banking systems under this market must operate within the framework of
the religion, based on Quran and Sunnah. The law that binds this finance market is
popularly known as the Sharia Law. The main difference between the banking system
in the Islamic manner and the conventional is the prohibition of Riba, which is the
interest imposed on money itself. The banking framework used under Islamic manner
is known as Profit-Loss Sharing (PLS) mechanism.
1.2 Background History
The period of low volatility of business cycle has been around from 1985-2007, where
the crisis put an end to it.
Source: National Income and Product Accounts
Figure 1-Period of Great Moderation presented by Annual GDP growth over
time
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On the other hand, the concepts adopted by the Islamic finance system are not new
since it rooted from the barter system. But, the modern Islamic Banking system is
considered a recent phenomenon. In Imam and Kpodar (2010) report, they tracked the
recent establishment of this banking system from the 1960s appearance. Murdoch
further discusses the timeline in a Reuters article in 2009, which is summarized in the
flowchart below.
Source: Reuters, Sole (2007) and Author’s compilations
Figure 2-Diffusion timeline of Islamic Banking System
Updating the timeline of the Reuters article to a more current research, Sole (2007) has
stated that 300 Islamic Financial institutions and over 250 mutual funds have
complied with the Islamic principles. It was also found that the growth rates of the
industry have been impressive and about 10-15 percent per year. In the future, this
trend is likely to linger.
1950s-1960s
•First experiment done in Pakistan and Indian Sub-continent.
•Malaysia and Egypt pioneer ventures using the concept in 1960s.
1975
•First commercial bank in Dubai was established.
•The Islamic Development Bank opens in Jeddah, Saudi Arabia.
1979 •Pakistan pioneered to Islamize the banking system.
1983
•Malaysia established first official sharia-compliant Bank.
•Sudan develops the dual banking system (Conventional along with Islamic).
1984 •Iran begin to Islamize the banking system.
1985 •50 Financial Institutions offered Islamic Financial products around the Globe.
1990s •Other major banks followed offering the Islamic financial products
by 2000
•About 200 Islamic Financial institutions developed over $8 billion in capital. The countries range over Middle East, Southeast Asia, Africa, Europe and America
by 2007
•300 Islamic Financial Institutions and 250 mutual funds complied with the Islamic Principles around the Globe
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Therefore, the substantial diffusion of Islamic Banking throughout the past 40 years
cannot be overlooked. As Bashir (2007) has indicated in his paper, Islamic Banks have
successfully entered international markets. He stated ‘Islamic Banking is one of the
fastest growing banking industry segments worldwide, with an annual growth rate of
17 percent and asset base of US$ 23 billion for the past several years’ (p. 3). At first the
entry of the Islamic Banks were motivated by the need of the Muslims who refuse to
put their money in the Conventional Banks. Following on, the spread became more
prominent after the success of some Islamic Banks drew the attention of the Asian and
European countries. Some of the banks were then set up in countries that have
significant Muslim minorities in order to seize profit-making opportunities. It is
therefore important to acknowledge its impact to those countries.
Before we assess the effect of Islamic Banking system on the business cycle, it is
important to familiarize the reader with the operation of the system. They operate in a
manner different from the conventional banking system in various characteristics,
which are shown in Table 1.
Source: Adib1 (n.d.), Kayed and Hassan (2011) and Author’s compilation.
Table 1- Major Differences between Islamic & Conventional Banking System.
1 The complete URL of the webpage where the information is compiled in the table is per:
http://www.adib.ae/understanding-islamic-banking-0.
Characteristics Islamic Banking System Conventional Banking System
Framework Follows Sharia laws Follows secular banking laws
Prohibition of Gharar
Transactions that involve a lot uncertainty are not allowed. Example would be
options trading.
There is no such prohibition in derivatives trading of any forms.
Profit and Loss Sharing
Main paradigm used in the system. Banks also loses money if the investment fails.
One of the symmetric profit sharing is the Musharakah contract.
No such principle, the investor bears the losses and enjoys the gains as a
whole. The Banks are entitled to fixed fees stipulated in the contract.
Prohibition of Riba
Interest on money itself is prohibited. The banks gains by applying a certain mark up or fees on the financing resource provided
to customers.
There is no such prohibition, as long as the customers meet the
application requirement, interest will be charged according to the credit
standing.
Industry
No trading activities on certain industries that deals with alcohol, drugs, gambling and others that are considered unlawful
under Sharia law.
There is no such prohibition on any industry trading activities.
Prohibition of Maysir
There is a prohibition on transactions that involve speculation.
No such prohibition on the assets traded in the conventional system.
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1.3 Significance
The question is whether the existence of Islamic Banking system could help explain the
research debate about the sources of Great Moderation.
The main idea of this research is to test the significance of the relationship between the
two events. The implication of testing the relation is to take into account the effect of
Islamic finance on explaining the volatility of the business cycle for future policy
making activity. The volatility is important in policy making because the greater the
volatility, the greater the uncertainty segment embedded on it. If the sources of
stabilizing volatility are found, more robust policies are implemented and fewer shocks
will affect the system.
This research paper will be divided into several sections. Section 2 will enlighten the
literature regarding the topic of interest. I will design the research in Section 3,
describe the method in Section 4 and present the results in 5. The results will be
discussed in Section 6. Suggestions for further research will be illustrated in Section 7.
Lastly, the conclusion of the paper will be deduced in Section 8.
2. Literature Review
Various studies have been conducted in regard to the sources of declining output
volatility and existence of Great Moderation. Although, Gali and Gambetti (2009)
agreed that there is some consensus among the studies on the existence and the period
of the Great Moderation, they also consented that there are controversies on its
interpretation. Creal et al. (2010) also affirmed that the causes of Great Moderation are
still much open to research. Creal et al. (2010) stated that Burns and Mitchell (1946) is
the key inspiration of other research in business cycle due to its immense contribution
in policy and decision-making.
Firstly, Kent et al. (2005) did a panel data study on 20 Organization for Economic Co-
operation and Development (OECD) countries and investigated the sources of Great
Moderation. There are four factors that have been proposed in the paper. Behavior of
the different components of GDP, policy efficiencies, structural changes in the industry
or just plain good luck. The good luck here is just an absence of bad luck for example oil
price shocks, which was absent during the Great Moderation period. They ran panel
regression from the period of 1973 until 2003, computed the GDP volatility on a rolling
window of 5-years and regress that as the dependent variable to the structural
indicators.
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Their main regression is as such:
Where is the standard deviation of annual growth of real GDP for country
is a vector of direct structural indicators at previous period such as product
market regulations and monetary policy regime.
is a vector of indirect structural indicators at the same period such as days
lost to labour disputes, trade openness, financial liberalization, inflation volatility
and fiscal policy volatility.
is a vector of other possible explanatory variable, in this case they have
included oil volatility since it is constant at a period of time for all the countries
regressed.
After running the regression, the results did not coincide with the literature and most
of the structural indicators appear to be insignificant in their results. They stipulated
that one reason behind this could be that some trend data may not have been taken
into account during 1973-1985, which might differs much with the trend of the rest of
the dataset. Using a single country was suggested as a control. Therefore, United
States dataset was proposed as a ‘locomotive’ in their paper.
Additionally, Gali and Gambetti (2009) believed that their paper has been able to shed
some light on the advantages of introducing the reasons of the existence of the Great
Moderation. They used volatility changes by computing standard deviations of output
for the pre and post-1984 data and compared the difference in volatilities using US
quarterly data from 1948-Q1 up to 2005-Q4. They utilized the Real Business Cycle
(RBC) Theory and applied Vector-Auto-regression (VAR) to examine the period. Their
paper focused on identifying the role played by different type of shocks that affects the
output volatility in the period of interest. In their research, they found that
Investment-type technology shocks and Non-technology shocks are the main rationale
behind the occurrence of the Great Moderation. This finding confirms the results of
Justiniano and Primiceri (2008) and Fisher (2006) who identified that Investment-
related shocks dominate the reasoning behind the decline in volatility of output growth.
In addition, Justiniano and Primiceri (2008) findings also suggest that investment
shocks are the triggering factors for other key macroeconomic variables changes in the
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cycle. The only thing that differs in their research was a larger dataset and the use of
Dynamic Stochastic General Equilibrium (DSGE) model as a method of estimation.
Following on, Neumeyer and Perri (2005) test some variables that move the business
cycle and found that real interest rates are countercyclical for emerging economies and
acyclical for developed economies. They performed their experiments in a
computational manner and focused on data from Argentina for the period 1983-2001.
Their conclusion was based on 5 developing countries and 5 other developed economies
under study. Moreover, they found that the extent of country risk in developing
countries affects the degree of countercyclical movements of real interest rates to the
cycle.
Then, Benati and Surico (2009) did a similar study focusing on United States, but used
different methods to investigate which of the sources in the list contributed to the
existence of Great Moderation. They used Structural VAR method to test the validity of
good luck reasoning. They used data of pre- and post-Great Moderation and found that
the period of interest is more volatile than the other two segments. Subsequently, they
used DSGE model that suggests that systematic component changes in GDP and the
low variance of investment are the main justification for Great Moderation to reign.
The literature focus then shifted to the investment reasoning. Salahuddin and Islam
(2008, p.21) have stated ‘Investment is the nucleus of an economy’. According to them,
investment plays a vital role in economic growth. So, in order to prove their theory of
accelerated growth, which can be caused by investment, they did a panel data study on
97 randomly selected developing countries on investment that includes both public and
private as the dependent variable from 1973 to 2002. The study done in that paper
confirms the significance of investment to empirics of growth and therefore influences
the economy to a great extent.
Building on the importance of investment, Chishti (1985) concluded that the amplitude
of all phases in business cycle under an Islamic economy would be smaller than in a
conventional economy. The main rationale that follows the argument is the instability
that is transmitted through the investment process that differs under the two systems.
He used Minsky Investment theory to reach the conclusion stipulated before. According
to the latter theory, the fragility of the financial system depends on the relation
between its financing decision (cash commitments) and their profits (cash flow). The
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extent of investment therefore depends on the two variables. He used a phase diagram
to explain the relation.
Source: Chisthi (1985)
Figure 3- Phase Diagram of Investment
The figure shows that investment grows as external financing needs increase and
becomes more stringent as represented by the f=0 line. On the other hand, when the
cash flows increases there is more scope for investment but at the same time limited to
its savings. Therefore, the need to rely on external financing surfaces with time, as
represented by the g=0 line. As a result, a balance around the circle represented in the
central segment of the graph has to be maintained.
Moreover, he postulated in his paper that under Islamic Financing scheme, investment
focused only on productive purpose therefore creating a link between the two variables.
The bond between payment commitments and cash flows helps to move both variables
together, hence forming stability in the system. The gap is thus minimized greatly
under the Islamic system at micro-investment level.
In this paper, we will examine the effect at macro level and the relation of the two
events from an elevated view. Imam and Kpodar (2010) investigated the diffusion of
Islamic Banking at the macro level using cross-country Poisson distribution regression
during the period 1992-2006. The sample consists of 117 countries and their hypothesis
was to find out the factors that help the spread of Islamic Banking during the years.
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Some of the factors that found to be explanatory of the hypothesis are the share of
Muslims in the country, income per capita, and the respective country’s distance to
Major Islamic Centres. Moreover, higher interest rates impact negatively on the
diffusion of Islamic Banking. Evolution of oil prices over the years also serves as a
great explanation for the spread of Islamic Banking. The stability of the economy and
its trade with the Middle East are also conducive in its contribution to the variable
tested. The highlight of the findings in this paper suggests that the September 2011
attacks in United States has nothing to do with the growth of Islamic Banking,
escalating oil prices are indeed the real driver.
Beck et al. (2013) compared the Conventional Banking system with the Islamic
Banking system in terms of cost efficiency, asset quality, stability and business
orientation. Using Bankscope’s database, they sample the largest 100 banks in terms of
assets within a country for the period of 1995-2007, pre financial crisis. After
elimination of outliers from the sample, they tested two different sample datasets, one
with all the countries and another with only countries that practice both Islamic and
Conventional banking Systems. Then, they ran two different panel regressions and the
empirical findings suggest very little or insignificant differences between the two
systems in terms of the areas discussed. The main difference between the two sample
data is the second smaller sample includes a variable of percentage of Islamic Banks as
compared to Conventional Banks in the countries that practice Islamic Banking. The
second sample is referred to Islamic countries. However, with the second panel dataset,
the estimates indicate that those countries with a larger concentration of Islamic
Banks are more cost effective but are less stable than those of lower concentration.
Lastly, I have summarized the literature above in a tabulated format and added the
usefulness for this research.
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Source: Literature Review section and Author’s summary
Study object
Authors Published
year Period of study Method Findings
Useful for Research
United States
Gali and Gambetti
2009 1948-2005
Compared volatility changes between pre and post Great Moderation period using VAR method with the application of RBC theory.
Investment-type technology shocks are the main rationale under Great Moderation.
Focus on Investment
United States
Creal et al. 2010 1953-2007 Stochastic volatility is assumed in the model to predict business cycle indicator that vary over time.
Structural breaks occur pre and post 1984, concludes Great Moderation is open to research.
Research motivation
20 OECD countries
Kent et al. 2005 1973-2003
Computed GDP volatility by rolling window of 5 years and regressed as dependent variable. Panel regression for the period.
Trend in output volatility is the main reason for decline in magnitude of global shocks.
Computation of GDP volatility and Inflation volatility is an important variable.
United States
Justiniano and
Primiceri 2008 1954-2004
Using DSGE model to investigate the sources of shifts of volatility in the US during the postwar period.
Investment shocks is key factor in business cycle changes
Focus on Investment
10 Countries
Neumeyer and Perri
2005 1983-2001 Computational experiments to evaluate the role played by interest rate shocks to the economy.
Real interest rates are countercyclical for developing and acyclical to developed economies.
Real interest rate as a variable and Developing country dummy.
United States
Benati and Surico
2009
2000 simulations pre Oct 1979 and post Volcker.
Structural VAR and DSGE model to investigates the sources of Great Moderation existence.
Systematic component changes in GDP and low variance of investment are the main reasons.
Focus on Investment
97 Developing countries
Salahuddin and Islam
2008 1973-2002 Investment as the dependent variable Confirms that Investment is the nucleus of an economy
Focus on Investment
Qualitative Model for
firms Chishti 1985 Not applicable
Using Investment theories to develop two differential equations. Formulated relation between financing and investment decisions at a micro-level.
Amplitude of all phases in business cycle under Islamic economy is smaller as compared to the conventional system
Country level of investment is an aggregate of micro-firm behaviors.
117 countries
Imam and Kpodar
2010 1992-2006 Using Poisson distribution method to regress factors that might affect the growth of Islamic Banking.
Oil prices are real driver of Islamic Banking growth
Oil Volatility is important to be taken into account.
100 largest banks
Beck et al. 2013 1995-2007 Panel regression of cross-country regressions of two different samples.
Islamic Banks are more cost effective but less stable.
Method of sub-panels are adapted
Table 2 - Summary of Literature Review and Usefulness to the Research
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3. Research Design
3.1 Sample Data Description
The sample consists of 116 countries randomly selected from the pool of 214 countries
available during the period of 1985-2007. The countries selected in this sample are
presented in Appendix 9.1. The period selected corresponds to the Great Moderation
concept introduced to explained the period of low volatility in the business cycle before
the financial crisis breakout.
3.2 Dependent Variable
The Dependent variable to explain the volatility in the business cycle is closely proxied
by Gross Domestic Product (GDP) data of the countries. Therefore, I have extracted the
annual growth of GDP per capita data from those 116 countries. Further, the standard
deviation is computed over five-year period in a similar fashion as in Kent et al. (2005),
which result in the truncation of the data starting now from 1989 onwards. This
method is also justified in IMF report (2012, p. 167) where the standard deviation is
found by looking at a backward rolling 5-year window. The resultant variable is then
termed as the GDP volatility. The data is taken from the World Bank, World
Development Indicators (WDI) for this variable.
3.3 Independent Variables
The independent variables have been extracted from various sources due to the vast
nature of the variables to be included in the model. The next few subsections will
further describe the various sources.
3.3.1 Oil Volatility
The variable here is proxied by the price of crude oil. World crude oil prices are
established in relation to three market-traded benchmarks (WTI, Brent and Dubai) as
indicated by the International Energy Agency. The nominal spot prices here is
benchmarked by the Dubai market and expressed in US dollars per barrel of oil making
all countries to state the same price at each period of time. This data is extracted from
OECD statistics. The variable evolves over time as graphed below:
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Figure 4-Changes of Oil Volatility over time
Here, the volatility is computed in a similar manner by taking standard deviation over
five-year period. Many countries used the oil prices as an opportunity to introduce
Islamic Banking system as indicated in Bashir (2007) and Imam and Kpodar (2010),
which explains that oil price fluctuations will be an important variable in research. The
variable is useful to observe the effect of productivity shocks to the country’s GDP in
terms of its fluctuations.
3.3.2 Islamic Finance Dummy
The dummy is introduced to distinguish those countries that practice Islamic finance
regardless of the percentage of its participation in the area. This is done by taking into
account the existence of at least one Islamic bank in the country examined. The
rationale behind the inclusion of this variable is to test the theory proposed in Chisthi
(1985), which states that the amplitude of the business cycle under an Islamic Economy
is lower than in a Conventional system. Those countries that practice Islamic Banking
therefore take the value 1 and 0 otherwise. The list of the countries that practice
Islamic banking currently, have been extracted from the Association of Islamic
Banking Institutions Malaysia website.
3.3.3 Developing country Dummy
The dummy here introduced is to substantiate our literature that summarizes that
developed countries behave in a different manner towards the business cycle variation
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as compared to those that is still emerging. This has been backed up by Neumeyer and
Perri (2005) research findings.
The list of developing countries is extracted from International Statistical Institute
website, which is effective for the whole year 2013. Those that are developing therefore
take the value 1 and 0 for the developed ones. The site defined that the Countries with
Gross National Income (GNI) per capita less than US $ 11,905 are considered as
developing countries in the list.
We can represent the two dummy variables in a graphical view in order to have an
indication of the sampled countries characteristic2 as per below.
We can see from the table of 116 countries below, it is quite rare to find developed
countries that practice Islamic Banking.
In the table on the next page, we can see that the majority of the countries lie in the
bottom-right box of the matrix. This means 51 countries out of the list of developing
countries do not practice Islamic Finance. The list of the countries in the other
categories is represented in the list in full on the following page.
2 The characteristic here represents inherent feature of the country, that is, the developing characteristic
and an existence of the Islamic Banking system.
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Table 3 - Relation between Developing Dummy and Islamic Finance Dummy
3 Countries that practice Islamic Banking take the value 1 and 0 otherwise. 4 Developing countries takes the value 1 and 0 for developed ones.
3
1
Brunei Darussalam
Cyprus
Israel
Singapore
Switzerland
United Kingdom
United States
Algeria
Azerbaijan
Bangladesh
Egypt, Arab Rep.
Ethiopia
Gambia, The
Indonesia
Iran, Islamic Rep.
Jordan
Kazakhstan
Kenya
Malaysia
Mauritania
Mauritius
Pakistan
Philippines
Russian Fed
Senegal
South Africa
Sri Lanka
Sudan
Syrian, Arab Rep.
Tanzania
Thailand
Tunisia
Turkey
Uganda
Yemen, Rep.
0
Australia
Austria
Bahamas
Barbados
Belgium
Canada
Czech Republic
Denmark
Estonia
Finland
France
Germany
Greece
Hong Kong
Hungary
Iceland
Italy
Japan
Luxembourg
Macao
Malta
Netherlands
New Zealand
Norway
Poland
Portugal
Slovak Republic
Slovenia
Spain
Sweden
Trinidad &Tobago
Albania
Argentina
Armenia
Belarus
Belize
Benin
Bolivia
Botswana
Brazil
Bulgaria
Burkina Faso
Cambodia
Cameroon
Cape Verde
Chad
China
Congo Dem.Rep.
Congo, Rep.
Costa Rica
Cote d’Ivoire
Dominican Rep
Ecuador
El Salvador
Gabon
Guatemala
India
Korea, Rep
Kyrgyz Republic
Latvia
Lesotho
Lithuania
Macedonia, FYR
Madagascar
Mali
Mexico
Moldova
Morocco
Mozambique
Myanmar
Panama
Papua New Guinea
Paraguay
Peru
Romania
Rwanda
Swaziland
Togo
Ukraine
Uruguay
Zambia
0 1
4 Developing Dummy
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3.3.4 Investment
Gali and Gambetti (2009), Justiniano and Primiceri (2008), Benati and Surico (2009)
and Salahuddin and Islam (2008) would agree that Investment is one of the chief
explanatory variables to explain the fluctuations of the business cycle. The variable
taken to represent Investment is known as Gross Capital Formation in the database
World Bank (WDI). It represents the outlays on any additions to the fixed assets of the
economy and changes in the level of inventories as expounded in the variable catalog.
The variable is represented as percentage of Gross Domestic Product (GDP). The
inclusion of this variable is necessary to measure the country’s GDP growth in a more
comprehensive manner.
3.3.5 Inflation Volatility
The variable for inflation is extracted from World Bank (WDI). The variable involved
was measured by the Consumer Price Index (CPI) since it reflects the direct impact of
acquisition of basket of the goods and services that will cost the consumer (IMF, 2012),
unlike the variable measured by GDP deflator affecting the economy as a whole. This
variable is an indirect indicator to measure the effectiveness of monetary policies
implemented in a particular country and its stability. Kent et al. (2005) agreed that
this variable is indeed one of the main structural change indicators of the business
cycle volatility.
3.3.6 Real Interest Rate
As suggested by Neumeyer and Perri (2005), real interest rates’ behavior is important
to the business cycle movements. This variable extracted from the World Bank (WDI) is
the lending interest rate adjusted for inflation.
3.3.7 Credit
This variable plays a vital role to explain how financial institutions affect growth
volatility, which elucidates the financial resources provided by the banks to the private
sector as a percentage of GDP. Easterly et al. (2000) confirmed the role stated, taken
the variable to measure the financial depth in their research. This variable that was
extracted from World Bank, the Global Financial Development Database as Bank’s
private credit to GDP, was also used to measure the extent of financial system
development in the country and their contributions towards the changes in GDP.
3.3.8 Trade Openness
Student no: 620029286 20
This variable is closely proxied by the sum of exports and imports across the countries
as a percentage of their GDP also supported in IMF (2012, p.167). The data is thus
obtained from the World Bank (WDI) database as well. The usefulness of this variable
is undoubtedly apparent due to its direct relation to the computation of any country’s
GDP.
3.3.9 Islamic banking concentration
This paper has adapted the Beck et al. (2013) method of panel data estimations, where
the percentage of Islamic Banking in Islamic countries is taken as a variable and
applied to a different dataset. The list of banks has been extracted from the Association
of Islamic Banking Institutions Malaysia site. Then, acknowledging the concentration
in each country, a percentage of total Islamic banks existing up to date as compared to
the whole pool is then computed.
4. Statistical Methodology
The method in my statistical research will be mainly focused on running a panel data
analysis on the variables explained across the countries in the earlier section. Stata5 is
the main software used to run the commands for this research. The method is largely
motivated by Kent et al. (2005) regression but adapted to suit the research focus of this
paper. The adaptations will be explained in this section in detail. All the variables are
extracted based on annual data during the period of the Great Moderation that is of
great interest in this paper. The main advantage in using panel data research is its
ability to embed variations both across countries and over the time period under study.
This is because engaging plain time-series method will neglect the possible correlation
across countries and cross-section methods will fail to take into account the
heterogeneity effect. As a result, the country-specific effects like the Islamic Finance
and developing country characteristic can be captured by using panel data since it
addresses the problem of biasness and inconsistencies in the coefficient estimates that
might occur under Ordinary Least Squares method.
4.1 Panel Regression
After refining the dataset due to missing values, the regression is finally run over the
period that ranges from 1991-2007. The regression equation is as follows:
5 The Stata log files have been compiled and are available upon request.
Student no: 620029286 21
Where:
= Standard deviation of annual growth of GDP per capita for country i
= Constant term
= Standard deviation of oil price per barrel in US dollars for period t.
= Dummy variable for existence of Islamic finance banking system for country i.
= Dummy variable for Developing country characteristic for country i.
= Vector of independent variables that affect GDP volatilities such as
Investment, Trade Openness, Credit, Real interest rate and Inflation volatility.
First, this panel will use a sample of 116 countries. Then, various regressions are going
to be run from which certain countries will be dropped due to missing values in the
data. Therefore, the sampled countries are adjusted to a set of 102 and 89 countries as
listed in Appendix 9.2 and 9.3 respectively. The variables regressed for the different
sample sizes are summarized by the � symbol in table 4.
Variables Panel-116 Panel-102 Panel-89
Developing � � �
Islamic Finance � � �
Investment � � �
Oil Volatility � � �
Inflation Volatility � � �
Trade � � �
Interest � � �
Private credit � � �
Table 4- Sub-division of main regression panel
There are a few statistical tests that are important prior to the usage of the data in the
panel regression. This is necessary in order to equip the reader with a rough indication
on the relationship between the variables. These few tests are performed based on 89
countries since some country data are lacking if the variables are to run together.
4.1.1 Cross correlation between the variables
This correlation matrix is computed in order to test whether the correlation amongst
the variables is significant at 5% level.
Student no: 620029286 22
GDP volatility Developing
Islamic Finance
Investment Oil Volatility Inflation Volatility
Trade Interest Private credit
GDP volatility 1.0000
Developing 0.2166*
(0.000) 1.0000
Islamic Finance
-0.1278* (0.0000)
0.1557* (0.0000)
1.0000
Investment 0.0759*
(0.0036) 0.0629*
(0.0000) -0.0330 (0.2047)
1.0000
Oil Volatility -0.1694* (0.0000)
0.0000 (1.0000)
0.0000 (1.0000)
0.1006* (0.0001)
1.0000
Inflation Volatility
0.2455* (0.0000)
0.1034* (0.0001)
-0.0751* (0.0039)
-0.0306 (0.2453)
-0.0852* (0.0011)
1.0000
Trade 0.0140
(0.5887) -0.1943* (0.0000)
-0.0193 (0.4532)
-0.0022 (0.9334)
0.1154* (0.0000)
-0.0522* (0.0455)
1.0000
Interest -0.0561* (0.0345)
0.0742* (0.0051)
-0.0423 (0.1104)
-0.0501 (0.0613)
-0.0709* (0.0074)
0.0208 (0.4341)
-0.0817* (0.0020)
1.0000
Private credit -0.2362* (0.0000)
-0.5992* (0.0000)
0.0899* (0.0006)
-0.1058* (0.0001)
0.1116* (0.0000)
-0.1318* (0.0000)
0.2671* (0.0000
-0.1172* (0.0000)
1.0000
Table 5- Correlation matrix of Regression variables
* Significant at 5% level
There is a linkage between correlation and multi-collinearity. High correlation may
increase the chances of multi-collinearity to arise. Although many of the correlations
are significant in the table above, the highest cross correlation shows between the
variable private credit and developing dummy (-0.5992). This indicates there is a strong
negative relationship between these two variables. The next highest significant value
in line is the relation between private credit and trade openness that is positively
related (0.2671). Although most of them are significantly correlated, the correlations
between the variables are not vey high at a glance. In section 4.3, some specification
tests will be further performed taken into account this indication of correlation.
However, it is advisable to run through the multi-collinearity test to ensure the
regression does not suffer from it.
4.1.2 Descriptive Statistics and Pattern
The table below is to summarize the statistics of the variables to be used for the
regression and to have a light indication on the variance of the factors being
considered.
Student no: 620029286 23
GDP
volatility Developing
Islamic Finance
Investment Oil
Volatility Inflation Volatility
Trade Interest Private credit
Mean 2.9709 1.6404 1.2809 5.7930 1.2975 38.7704 85.4847 7.7064 47.1607
Maximum 30.8131 2.0000 2.0000 223.0843 3.7817 3287.5730 436.9581 374.309 272.8089
Minimum 0.0520 1.0000 1.0000 -87.2000 0.3985 0.0421 0.3088 -91.7244 0.1152
Standard deviation
3.0064 0.4800 0.4496 15.9712 0.9824 257.6522 54.8147 15.9256 42.3844
Observation 1505 1513 1513 1474 1513 1474 1510 1424 1441
Table 6- Description statistics of Regression Variables
4.1.3 Variance Inflation Factor test
This test helps to identify any multi-collinearity that might occur between the
variables. This problem as explained by Verbeek (2004) occurs when a linear
relationship among the independent variables leads to unreliable regression estimates.
Variable VIF
Developing 1.69
Islamic Finance 1.11
Investment 1.04
Oil Volatility 1.06
Inflation Volatility 1.03
Trade 1.11
Interest 1.06
Private credit 1.73
Table 7- Variance Inflation Factor test
The test is computed by using the individual R2. The formula is as follows:
The threshold is either 5 or 10 depending on the sample size as indicated in Salahuddin
and Islam (2008). All the above results are below the level; therefore we can deduce
that the variables in the regression are free from multi-collinearity problem.
4.2 Sub-panel regression
This regression only includes those countries deduced from 4.1 regressions that
practice the Islamic banking system and refining the sample into those countries that
have complete dataset. This panel has been adapted from the paper done by Beck et al.
(2013) by concentrating the Islamic countries data only. The equation has therefore
been reformed to:
Student no: 620029286 24
Where:
= Percentage of concentration of Islamic banking in a country i as compared to
the total Islamic banks.
The figure presented below aims at depicting the number of Islamic banks in each
country across the globe. Only 49 countries display the presence of Islamic Banks. The
concentration in a particular country is then computed by calculating the proportion
between the number of Islamic Banks present in that country with respect to the total
number of Islamic Banks.
Student no: 620029286 25
Source: Association of Islamic Banking Institutions Malaysia, Author’s compilations
Figure 5- Number of Islamic Banks across the Globe
0
5
10
15
20
25
30
Number of Islamic Banks across countries
Student no: 620029286 26
The 49 countries shown in the figure above are not fully represented in the original 116
sampled countries. From Table 3, we can observe that the first row of the matrix
represents the Islamic countries, which consists of 35 countries in total. Similarly, after
some adjustments to missing values in the data, these 35 countries will be incorporated
to several regressions. Therefore, the latest 35 countries are adjusted to a set of 32 and
23 countries as listed in Appendix 9.4 and 9.5 respectively. The variables regressed for
the different samples are summarized by the � symbol in table 8.
Variables Panel-32 Panel-23
Developing � �
Islamic Finance � �
Investment � �
Oil Volatility � �
Inflation Volatility � �
Trade � �
Interest � �
Private credit � �
Table 8- Sub-division of sub-panel regression
Comparing the volatility in 4.1 and 4.2 dataset, we are depicting the graph of the GDP
volatility over time in the below figures. We are only comparing those samples that have
no missing values on any variables as a whole. This justifies the comparison between the
89 countries sampled from regression 4.1 and 23 countries from regression 4.2. The
comparison graphs suggests that the concentration of most countries’ scatter plot lie
around 0-10% on Figure 6 and 0-4% on Figure 7. Therefore, the graphs show a rough
Figure 6- Volatility of 89 countries over
time
Figure 7- Volatility of 23 countries over
time
Student no: 620029286 27
indication of the hypothesis of low GDP volatility of Islamic countries represented by
figure 7 below.
4.3 Method of Estimation
The Panel data proposed has been justified in 4.1 due to its advantages of dealing
successfully with both cross sectional and time series data. However, another aspect
that is important is the method of estimation of the regression tested. There are four
methods as summarized by Verbeek (2004) and adapted to the regression 4.1, in brief it
estimates in the following manner:
1) Between Estimator:
Using Regression in 4.1:
Then compute the individual’s country average across time and total average across
both country and time:
The regression under this method is transformed by subtracting (2) from (1), the
resultant regression:
Then, the coefficients are determined from this new regression. There is a useful
implication to note that under this regression, the oil volatility term is eliminated due
to the nature of the estimator of using the cross sectional part of the data. The oil
volatility term does not change across countries, which justifies its redundancy.
Moreover, the independent variables in this case are exogenous and do not correlate
with the time invariant effects, i.e., the two dummy variables.
2) Within Estimator [Fixed Effects (FE) Estimator]:
Using Regression in 4.1:
Then compute the individual’s country average across time:
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The regression under this method is transformed by subtracting (4) from (3), the
resultant regression:
Then, the coefficients are determined from this new regression.
Interestingly, the implication in this regression is the mirror image of the method in
regression 1). In this, the time-invariant variables such as Islamic Finance and
Developing Country dummy are therefore eliminated. This is because in contrast to the
method in 1), this method estimates the time series portion of the dataset within a
country individually.
In this case, the independent variables are suppose to be exogenous as well but in
contrast to the method in 1), they are allowed to correlate with the dummy variables.
3) Ordinary Least Squares (OLS) Estimator:
This method exploits both dimension of time and cross section. It is widely known as
the pooled OLS estimator. It directly estimates the original equation in (1) without any
transformation. This is based on the assumption that each observation comes from an
independent, identical distribution (iid), that is . The drawback using this
method is that the panel structure is ignored due to the characteristic of a pooled OLS
method that weighs each observation uniformly. This may not be optimal in practical
data sets. Although the estimates may be unbiased and consistent, it fails to be the
Best Linear Unbiased Estimator (BLUE). The ‘Best’ means the most efficient
estimator, which is, achieving the least variance. Therefore, under panel data, OLS
method might not accomplish that objective of being the ‘Best’.
4) Random Effects Estimator (RE):
The last method in this case is a randomization of between and within estimator. This
method is also known as the Generalized Least Squares (GLS) estimator. Although this
method is a mix between 1) and 2), the strict exogeneity and no correlation are
assumed in this method. The key substance in this method is the determination of .
The value of will determine the extent of randomization of the two extreme
estimators discussed in 1) and 2). The regression in this case is as follows:
θ - √σ2ε / Tσ2ν σ2ε) (5)
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If θ is 0, the random effects estimator will be identical to the one estimated by OLS
method in 3). If θ is 1, the estimator will then be equal to the one in method 2), that is,
the within estimator.
Since the value of θ is vital, the computation of the entire five samples are presented
below:
Stata computes the value according to equation (5); by running the random effects
regression on the sample with ‘theta’ command.
The usefulness of θ is quite varied in some ways. Not only it can roughly indicate the
tendency of type of estimator that will be estimated under this method, but it also
measures the degree of biasness of the estimator. The extent of biasness can be
explained in detailed in the subsequent Hausman test in this section.
Now the question arises: which model estimates can we rely on for our prediction? The
first method estimates changes in the variables between the countries over a fixed period
of time. The second method indicates within a country, how the extent of change in the
variables affect the GDP volatility over time. However, these areas are not of interest in
this paper.
The Ordinary Least Squares and Random effects method combines both this method and
takes into account the changes across both time and countries. Illustrating these results
in mind, the pooled OLS and RE method deems to be useful for this research.
Hausman test
Hausman (1978) suggested a test to decide in a more convincing manner on the
appropriate method for panel regressions comparing FE and RE. The test is clearly
expounded in Verbeek (2004) where the hypotheses are:
H0: There is no significant correlation between the two dummy variables with the other
independent variables (investment, oil volatility, inflation volatility, trade openness, real
interest rate and credit).
Implication of the null hypothesis: Fixed effects estimator is consistent and not efficient.
Random effects estimator is both consistent and efficient.
Table 9- Computation of transformation parameter in Random Effects Model
Panel-89 Panel-116 Panel-102 Panel-32 Panel-23
θ-Value 0.6381 0.6366 0.7643 0.6806 0.6228
Implication The value is between 0 and 1, more tendencies towards within estimator effect.
Student no: 620029286 30
H1: the null hypothesis of no significant correlation does not hold.
Implication of the alternative hypothesis: Fixed effects estimator is both consistent and
efficient. Random effects estimator is now inconsistent but still efficient.
The distribution is assumed to follow Chi-square asymptotically with degrees of freedom
equal to the dimensions of the estimates.
From both hypotheses, we can deduce that rejection of the null indicates that fixed effects
method is a better explanatory model for the regression tested and the reverse is true on
the failure of rejection of the null.
The test results are as follows for both 4.1 and 4.2 regressions:
Panel-89 Panel-116 Panel-102 Panel-32 Panel-23
Test
statistic 7.19 16.48 5.69 2.24 3.03
P-value 0.3036 0.0024 0.2233 0.8150 0.8055
Decision Reject H0 Fails to reject H0 Reject H0
Implication Choose RE Choose FE Choose RE
Table 10- Hausman test
With the results in the table, we would then proceed with the method suggested by the
tests. Therefore, except for 116 sets of countries in Appendix 9.1, the other sample sizes
suggested that random effects would result in consistent estimates. In the panel of 116
countries, there exist a correlation between the dummy variables and other
independent variables. If random effects continued to be estimated for this sample,
then the results would be biased and the extent of biasness can be illustrated using the
value in Table 9.
Student no: 620029286 31
5. Results
From the previous subsection, we can conclude that focus can be concentrated on two
methods of estimation, which is OLS and RE method. However, for the panel of 116
countries, we would then focus on OLS and FE method justified by Hausman test
results in Table 10.
5.1 Panel Regression
Model
Panel-89 Panel-116 Panel-102
Variables OLS RE OLS FE OLS RE
Developing 0.9924*** (0.1828)
1.204*** (0.3693)
1.4835*** (0.1351)
1.2875*** (0.1610)
1.1570** (0.4746)
Islamic Finance
-0.6079*** (0.1569)
-0.7712** (0.3507)
-0.6299*** (0.1331)
-1.0290*** (0.1678)
-1.1571** (0.5067)
Investment 0.0088* (0.0051)
0.0004 (0.0044)
0.0189*** (0.0038)
0.0033 (0.0032)
0.0017 (0.0012)
-0.0007 (0.0009)
Oil Volatility
-0.4313*** (0.0727)
-0.3749*** (0.0644)
-0.5248*** (0.0622)
-0.4882*** (0.0555)
-0.4015*** (0.0774)
-0.4563*** (0.0606)
Inflation Volatility
0.0022*** (0.0003)
0.0021*** (0.0003)
0.0005*** (0.0001)
0.0005*** (0.0001)
Trade 0.0048*** (0.0013)
0.0044* (0.0025)
0.0045*** (0.0012)
0.0049 (0.0038)
0.0049*** (0.0014)
0.0062** (0.0031)
Interest -0.0119** (0.0061)
-0.0089 (0.0060)
-0.0158*** (0.0056)
-0.0104** (0.0051)
Private credit
-0.0058*** (0.0021)
-0.0041 (0.0032)
Constant 2.3530*** (0.3873)
2.1778*** (0.7807)
1.4212*** (0.3063)
3.0871*** (0.2988)
2.4082*** (0.3757)
2.8641*** (1.0386)
R2 Overall 0.1474 0.1438 0.1247 0.0469 0.0732 0.0686
Table 11- Panel Regression results
Standard errors are shown in parentheses.
* significant at 10% level
**significant at 5% level
***significant at 1% level
Let us consider the first OLS regression on the set of 89 countries, which was run over
all explanatory variables considered under the study. Being a developing country, the
GDP volatility increases by 99.2% more than the developed economies for every unit
change in the volatility. In the same manner, being a country that practices Islamic
Finance, for every change in the volatility, it will reduce by 60.8% more than those
countries that do not practice.
Student no: 620029286 32
A percentage extra invested will affect the GDP volatility in a positive manner by
increasing it by 0.8%. However, every unit increase in oil volatility will affect the GDP
volatility in a negative manner by 43.1%, which can be backed by literature as in Guo
and Kliesen (2005). They stated that when oil prices are too volatile, there is a
reduction in GDP changes, since there is a shift of focus due to uncertainty in resource
allocations. Therefore, investment for growth of the country is delayed, by minimizing
too much change in GDP’s composition.
Moreover, the opposite is seen regarding the effect of inflation volatility. If inflation
volatility increases by one unit, then the GDP becomes more volatile by 0.2%. Following
on, a 1% increase trade, which represents the flows of exports and imports, would
increase the GDP volatility by roughly 0.5%.
There are both negative impacts on the other two variables. Units increase in both real
interest rate and private credit will reduce the GDP volatility by 1.2% and 0.6%
respectively. In general for Fixed effects and Random effects, the direction of changes is
very similar only different in the percentage changes unless some of the estimates are
insignificant. This generalization applies to the different sample size of 116 and 102
countries shown in appendix 9.1 and 9.2 respectively.
Student no: 620029286 33
5.2 Sub-panel Regression
This regression is run on the equation discussed in section 4.2. The main difference
between both panels is the variable Islamic concentration and the countries regressed.
Those considered in this panel are the ones who practice Islamic Banking systems. Due
to limited data for some countries, complete regression was run on 23 countries and 32
countries are regressed without the variable interest rate. The lists of countries are
presented in Appendix 9.5 and 9.4 respectively. The results are presented as follows:
Model
Panel-32 Panel-23
Variables OLS RE OLS RE
Developing 0.4305
(0.3167) 0.8708
(0.7016) 0.7129** (0.3015)
0.9022 (0.5928)
Islamic Concentration 5.0346
(3.1747) 3.4013
(7.9787) -3.2665 (4.3973)
-5.9415 (9.4905)
Investment -0.0042 (0.0067)
-0.0156*** (0.0057)
-0.0240** (0.0094)
-0.0249*** (0.0081)
Oil Volatility -0.2286** (0.0918)
-0.2540*** (0.0773)
-0.1929** (0.0978)
-0.1823** (0.0853)
Inflation Volatility 0.0066*** (0.0008)
0.0047*** (0.0007)
0.1222*** (0.0174)
0.0925*** (0.0159)
Trade 0.0066*** (0.0016)
0.0113*** (0.0033)
0.0073*** (0.0014)
0.0109*** (0.0029)
Interest
-0.0262* (0.0142)
-0.0046 (0.0140)
Private credit -0.0064** (0.0030)
-0.0047 (0.0053)
0.0028 (0.0030)
0.0031 (0.0050)
Constant 1.7324** (0.6746)
0.6951 (1.4369)
0.4844 (0.6519)
-0.1658 (1.2156)
R2 Overall 0.2034 0.1706 0.2199 0.1910
Table 12- Sub-panel Regression results
Standard errors are shown in parentheses.
* significant at 10% level
**significant at 5% level
***significant at 1% level
The sub-panel regression results that is significant here have similar direction in terms
of their movements in relation to GDP volatility, except for Investment. The movement
of this variable is an interesting finding since now it is a negative relation contrast to
5.1 where it was positive. This is then now interpreted that taking into account
investments in countries that practice Islamic Finance only leads to less volatile GDP
Student no: 620029286 34
movement by at least 1.61% in contrast to the investments under a general economy in
5.1 regression increases the volatility.
On the other hand, regarding the purpose of the sub-panel regression, that is, the
inclusion of Islamic concentration appears to be insignificant in both sample data. This
can be due to the definition of the variable in this case which may not lead to a good
depiction of the Islamic concentration in the country. Therefore, at a glance, this sub-
panel may appear futile to estimate. Nevertheless, this regression has been able to
prove that investment in the selected Islamic countries induces the GDP to be less
volatile as compared to the 5.1 regressions.
5.3 Panel Validity tests
The two methods of coefficient estimates of Ordinary Least Squares and Random
Effects have been presented in the previous section. However, tests need to be
performed on whether the results of the estimates can be relied upon. This is necessary
as the interpretation of the estimates given above would only be correct if there is an
absence of serial correlation in the residuals and heteroskedasticity of the variance of
the estimates.
McGregor (n.d.) have visually illustrated the tests to perform in order to select the most
appropriate method of estimation. The figure below represents his illustration and
using that, the two tests performed subsequently will be justified.
Student no: 620029286 35
Source: McGregor6 (n.d.)
Figure 8- Flowchart of tests to select appropriate Method of Estimation
Ordinary Least Squares VS Random Effects
This test is a Lagrange Multiplier (LM) test by Breusch and Pagan (1979) testing for
any difference of weightage in individual observation added to sample. This test follows
chi-square distribution asymptotically with 1 degree of freedom. The test hypotheses
are as follows:
H0: There are no individual effects on each observation, that is σ2ν =0 in the equation
(5)
Implication of the null hypothesis: if the variance of individual observation reduces to
zero, a simple OLS estimator is applicable for the regression.
H1: the null hypothesis of no individual effects does not hold.
Implication of the alternative hypothesis: Rejection of the null denotes that there are
some different weightage in some observations in the data. Random estimator is
therefore appropriate.
6 Neil Foster McGregor presented the flowchart in his lecture slides of Lecture 6-Panel Data Econometrics at
the University of Vienna.
Student no: 620029286 36
Model
Test Panel-89 Panel-116 Panel-102 Panel-32 Panel-23
OLS VS RE 672.40
(0.0000) N.A.
1218.57 (0.0000)
390.46 (0.0000)
193.14 (0.0000)
P-values are presented in the parentheses.
Table 13- Model Selection test A
The test for all the samples therefore clearly rejects the null indicating that random
effects is a better model, substantiated by the p-value in the parentheses that are below
5% level.
Ordinary Least Squares VS Fixed Effects
With the help of Gregory Chow of Princeton University’s paper in 1960, we can
continue to select the most appropriate model by running a Chow test.
This test has the following hypotheses:
H0: There are no significant differences on each panel effect, that is, the individual
country effects are jointly zero.
Implication of the null hypothesis: if the effect of joint country effect reduces to zero, a
simple OLS estimator is applicable for the regression.
H1: the null hypothesis of no significant difference does not hold.
Implication of the alternative hypothesis: Rejection of the null denotes that there are
some different weightage in some country effect in the data. Within estimator (Fixed
Effects) is therefore appropriate.
It is therefore computed as follows:
Where:
RRSS- Restricted Residual Sum of Squares (if null hypothesis is true)
URSS- Unrestricted Residual Sum of Squares (if null hypothesis is false)
N-number of panel (countries)
T- number of period (years)
K- number of parameters tested.
Student no: 620029286 37
In this particular case, The Degrees of freedom is as follows:
Numerator: N-1= 116-2-1 = 113 (two of the countries eliminated due to multi-
collinearity.
Denominator: NT-N-K= {(116x17)- 116-119} = 1737
The critical value of F-distribution at (113, 1737) computed using excel formula at 5%
significance level = 1.2382.
Model
Test Panel-89 Panel-116 Panel-102 Panel-32 Panel-23
OLS VS FE N.A. 9.43
(0.0000) N.A. N.A. N.A.
P-value is presented in the parentheses.
Table 14- Model Selection test B
Here, the clear rejection is not only supported by the p-value below 5%, but also by the
test statistic of 9.43> 1.2382 (critical value at 5% significance level). This concludes
that we should use the Fixed Effects method to estimate the coefficients in this model.
Serial correlation
The presence of serial correlation in the residuals will cause the standard errors to be
smaller than the actual values. It is therefore important to detect if such phenomenon
exists, and then correct them. This test is conducted by using ‘xtserial’ command on the
earlier regressions in 5.1. Stata uses Woolridge test for serial correlation. Drukker
(2003) supports the Woolridge test due to its easy implementation and applications. In
the paper, he also simulated some evidence that the test has good size and power
properties in its application, making it more robust to rely on. This method does that by
using the residuals from the first-difference regressions of the variables. The
hypotheses tested are as follows:
H0: There is no serial correlation in the residuals, that is condition holds.
Implication of the null hypothesis: The correlation between the residuals will enable us
to rely on the standard errors estimated in the regression tested.
H1: the null hypothesis of no serial correlation between the error terms does not hold.
Implication of the alternative hypothesis: Rejection of the null denotes the reliance on
the standard errors in the regression is specious.
Student no: 620029286 38
Model
Test Panel-89 Panel-116 Panel-102 Panel-32 Panel-23
Serial Correlation
126.39
(0.0000) 112.56
(0.0000) 151.70
(0.0000) 187.28
(0.0000) 60.20 (0.0000)
P-value is presented in the parentheses.
Table 15- Serial Correlation validity tests
All the sample data rejects the null at 5% level, strong support of presence of serial
correlation in the error terms.
Heteroskedasticity
The presence of heteroskedasticity in the variance of the residuals breaks the
assumption of constant variance, therefore reduces the predictability of the estimates.
Consequently, it is important to verify that homoskedasticity assumption still holds.
There are two ways to conduct the test. The first test is executed by using the command
‘xttest3’ on the fixed effects regression. Stata by default uses a modified Wald Test to
perform the group-wise heteroskedasticity tests as specified in Torres (n.d.). According
to Verbeek (2004), the Heteroskedasticity test used for fixed effects regression can also
be used for Random Effects as long as the time invariant variable is independent and
identically distributed (i.i.d.). We have tested that the variable is iid as long as Random
effects is the model appropriate for the regression. This was confirmed in section 4.3
under - Hausman test.
The second is Poi and Wiggins (2001) Likelihood Ratio test. As explained by Sanchez
(2012), the test is executed by running ‘xtgls’ command on the regression of interest.
This method uses Maximum Likelihood to model the panel level heteroskedasticity.
Then, the following is to restrict homoscedastic assumption to the error terms. Using
the likelihood values has the benefit of looking whether the additional parameters
(covariances between panels) improves the model fit. The test is calculated using the
formulae:
Where denotes the log-likelihood function of the unrestricted and the log
likelihood function of the restricted estimator. The test follows a Chi-square
distribution based on asymptotically normal distribution.
Here, the first method is used and the results are as follows:
Student no: 620029286 39
Model
Test Panel-89 Panel-116 Panel-102 Panel-32 Panel-23
Heteroskedasticity-Wald test
160000 (0.0000)
90954.26 (0.0000)
120000 (0.0000)
12509.47 (0.0000)
7053.85 (0.0000)
P-value is presented in the parentheses.
Table 16- Heteroskedasticity validity test
From the Wald test, all the dataset leads to rejection of the null hypothesis, indicating
the presence of heteroskedasticity.
In the light of the results of all the above tests, the coefficients in Section 5 cannot be
relied upon due to its heteroskedastic and serially correlated error terms.
Therefore, we need to transform the regression results to take into account the
heteroskedasticity and serial correlation present on the panels.
In Table 17 below, the coefficient estimates are the same as presented in the results in
Section 5. The main modification is that the standard error in the parentheses are
estimated again to be robust to any heteroskedastic and serial correlation problem that
might affect the reliance on the estimates. Another important finding to note is that
some of the significant results earlier have deemed to be insignificant due to
transformed standard errors. This includes the investment in the sample of 32
countries, inflation volatility in 116 countries and the trade variable in 89 and 102
countries. However, the variables relate to each other in the same manner, hence the
sign is preserved. The Islamic Finance variable negatively affecting the GDP volatility
remains significant and noteworthy of discussion.
Student no: 620029286 40
Model
Panel-89 Panel-116 Panel-102 Panel-32 Panel-23
Variables RE FE RE RE RE
Developing 1.204*** (0.3619)
1.1570** (0.5252)
0.8708 (0.7901)
0.9022 (0.6978)
Islamic Finance
-0.7712** (0.3428)
-1.1571** (0.3670)
N.A. N.A.
Islamic Concentration
N.A. N.A. N.A. 3.4013
(7.1327) -5.9415
(7.1671)
Investment 0.0004
(0.0088) 0.0033
(0.0081) -0.0007 (0.0005)
-0.0156* (0.0095)
-0.0249 (0.0185)
Oil Volatility -0.3749***
(0.0814) -0.4882***
(0.1063) -0.4563***
(0.0998) -0.2540** (0.1140)
-0.1823* (0.1057)
Inflation Volatility
0.0021** (0.0008)
0.0005 (0.0004)
0.0047* (0.0028)
0.0925 (0.0819)
Trade 0.0044
(0.0031) 0.0049
(0.0068) 0.0062
(0.0044) 0.0113** (0.0045)
0.0109*** (0.0041)
Interest -0.0089 (0.0084)
-0.0104* (0.0061)
-0.0046
(0.0150)
Private credit -0.0041 (0.0043)
-0.0047 (0.0094)
0.0031 (0.0085)
Constant 2.1778*** (0.6785)
3.0871*** (0.5033)
2.8641*** (1.1068)
0.6951 (1.6307)
-0.1658 (1.5387)
R2 Overall 0.1438 0.0469 0.0686 0.1706 0.1910
Table 17- Transformed final model robust to heteroskedasticity and correlation
Student no: 620029286 41
6. Discussion
The present discussion is going to focus on the transformed model in Table 17.
Neumeyer and Perri (2005) has motivated this paper to take into account the difference
in behavior between developed and developing countries. The inclusion of the
Developing dummy variable has been fruitful in explaining that the Developing
country increases the GDP volatility based on the larger sample data regressions.
The creation of the sub-panel was motivated by Beck et al. (2013) who divided the
sample to explain the growth of Islamic Banks. Although the key variable of this paper,
that is, the Islamic Finance dummy variable has successfully explained the lower GDP
volatility effect during the period, the percentage of concentration included in the sub-
panel regressions fails to explain the same.
With this variable, we have tested Chisthi’s (1985) theoretical micro-investment model
on practical data sets. The finding therefore supports Chisthi’s (1985) adaptation of
Minsky Investment Theory that was built up to prove that the amplitude of the
business cycle in an Islamic Economy is lower than in a conventional economy, which
was implemented on a micro-firm level.
Another very important variable included in the model that was motivated by several
papers like Gali and Gambetti (2009), Justiano and Primiceri (2008), Benati and Surico
(2009), Salahuddin and Islam (2008) is investment. The emphasis placed on this
variable has attested to be effective. In the main panel, the effect was positive
indicating that higher investment will increase GDP volatility. Kayed and Hassan
(2011) have found that the conservative nature of investments usually made through
the Islamic system, leads to a more productive outcome, creating stability in the
economic system. In the sub-panel, the investment done in Islamic countries indeed
reduces the GDP volatility, which is in line with the literature by Kayed and Hassan
(2011). This therefore supports the theoretical model by Chisthi (1985) discussed
earlier in this section. The model will therefore be useful for future similar studies in
this area of research.
The importance of oil volatility seemed quite obvious in the results presented in Table
17, which is in line with Imam and Kpodar (2010) viewpoint. Inflation volatility and
GDP volatility move in the same direction independently of the sample difference. The
movement is as predicted in Kent et al. (2005).
Student no: 620029286 42
Trade openness is another structural indicator necessary to explain GDP movements as
highlighted by Kent et al. (2005). Again the direction, which is as, predicted in Kent et
al. (2005) holds for all sample sizes.
After transformation of the model, some of the interest rates coefficients are now
insignificant. Nonetheless in general, the model with random effects of 102 sample
countries proved to be significant and coincides with the literature that interest rate is
acyclical or countercyclical to the business cycle in Neumeyer and Perri (2005).
Following a similar reasoning, the private credit given for loans in countries is not
significant to explain the GDP volatility in contrast to Kent et al. (2005) where there
was a significant positive relation in one of the panel data models that they tested.
Overall, the literature from various authors referred to in the literature review and the
discussion has influenced this research in several areas. The contributions from those
authors have been compiled and adapted to provide a remedy to the research problem
in this paper.
Student no: 620029286 43
7. Limitations and Further Research
There are several inherent limitations that might affect the results of this paper. The
data for Islamic banking concentration is found by number of banks registered and set
up in each country and not taking into account the total number of branches of those
registered banks. The access to the number of branches compared to conventional
banks would be a better variable in the sub panel regression. This data would provide a
better representation of the Islamic Banking presence in each country, as it would
consider the intensity of the use of this banking system.
Moreover, the listed Islamic Banks in itself may not have administered according to the
binding principles stated in Quran and Sunnah, also popularly known as Sharia law.
According to Chong and Liu (2009) their banking operations try to imitate the
conventional system in order to remain competitive in the countries they are
established. As Beck et al. (2013) also supported this in their paper since they found
that the products offered in the Conventional and Islamic systems are structured in a
similar way and ‘a strong element of equity participation’ (p. 438) is found in the latter
system. Therefore, there is lack of uniformity in the implementation of the banking
principles, which hinders comparison of the data collected. As a result, this issue
imposes some inference limit on the generalization of the results presented in Table 17.
Further innovation can be adapted from Kent et al. (2005) discussion where they
suggested using the United States (US) data as a control country to compute the new
variables. Since their study did not include the Islamic Finance variable, further
research could consider using US as a control along with the Islamic Finance variable
to explain Great Moderation. The motivation of using United States as control would be
justified by the concept of Great Moderation being the country of its establishment.
The regression would therefore be:
The ‘Tilda’ as explained by Kent et al. (2005) represents the respective country’s
observation difference with the United States at a fixed period of time for each
observation. The oil volatility therefore will not change due to its property of being
capped to US oil price, which is universally the same at a fixed period of time.
Student no: 620029286 44
Another way of observing the hypotheses tested is by using time series approach. If
time series data were to be used focusing on United States, variations on the tests
could be done. Granger causality effects could be tested on the growth of Islamic
finance throughout the years affecting the GDP volatility. If the Islamic Finance
growth over the years appears to granger cause the GDP volatility, then it means the
former variable will be able to provide statistical significant information about the
latter variable. However, this effect does not mean the Islamic Finance variable causes
the changes in the volatility. It only aids in contributing significant information in
prediction.
Student no: 620029286 45
8. Conclusion
The changes in GDP volatility have been universally accepted to explain business cycle
fluctuations according to umpteen research papers. The Great Moderation concept was
quite a popular research motivation during its reigning years until the financial crisis
around the year 2007 took over its place. Since then not many papers continued to
pursue the understanding of this Great concept which was defined as a period of low
volatility in the business cycle over 1985-2007. According to the literature review, we
would classify it as a grey area since there is no consensus in the reasons of its
existence.
Our intuition is that the consensus not found in the literature might be due to some
missing explanatory variables such as Islamic Finance. The innovation introduced by
this paper was considering the presence of Islamic Finance as a determinant of GDP
volatility adding to the literature on this subject of interest. We found that indeed the
presence of Islamic Finance helps to reduce GDP volatility. This could be one of the
possible reasoning behind Great Moderation occurrence. The empirical regressions
provided support to the hypothesis tested and contributed to a more profound
understanding of the role of Islamic Finance in explaining the business cycle. Not only
would this finding be useful for understanding the past, but also it would help to
forecast and aid in policy making for the future.
Student no: 620029286 46
9. Appendices
9.1 Panel 116 countries
Albania Cote d'Ivoire Korea, Rep. Portugal
Algeria Cyprus Kyrgyz Republic Romania
Argentina Czech Republic Latvia Russian Federation
Armenia Denmark Lesotho Rwanda
Australia Dominican Republic Lithuania Senegal
Austria Ecuador Luxembourg Singapore
Azerbaijan Egypt, Arab Rep. Macao SAR, China Slovak Republic
Bahamas, The El Salvador Macedonia, FYR Slovenia
Bangladesh Estonia Madagascar South Africa
Barbados Ethiopia Malaysia Spain
Belarus Finland Mali Sri Lanka
Belgium France Malta Sudan
Belize Gabon Mauritania Swaziland
Benin Gambia, The Mauritius Sweden
Bolivia Germany Mexico Switzerland
Botswana Greece Moldova Syrian Arab Republic
Brazil Guatemala Morocco Tanzania
Brunei Darussalam Hong Kong SAR, China Mozambique Thailand
Bulgaria Hungary Myanmar Togo
Burkina Faso Iceland Netherlands Trinidad and Tobago
Cambodia India New Zealand Tunisia
Cameroon Indonesia Norway Turkey
Canada Iran, Islamic Rep. Pakistan Uganda
Cape Verde Israel Panama Ukraine
Chad Italy Papua New Guinea United Kingdom
China Japan Paraguay United States
Congo, Dem. Rep. Jordan Peru Uruguay
Congo, Rep. Kazakhstan Philippines Yemen, Rep.
Costa Rica Kenya Poland Zambia
Student no: 620029286 47
9.2 Panel-102 countries
Albania Finland Nicaragua
Algeria France Norway
Argentina Gabon Panama
Armenia Gambia, The Papua New Guinea
Australia Germany Paraguay
Bahamas, The Greece Peru
Bangladesh Guatemala Philippines
Barbados Hong Kong SAR, China Poland
Belarus Hungary Romania
Belgium Iceland Russian Federation
Belize India Rwanda
Bolivia Indonesia Sierra Leone
Botswana Israel Singapore
Brazil Italy Slovak Republic
Brunei Darussalam Japan Slovenia
Bulgaria Jordan South Africa
Cameroon Kenya Spain
Canada Korea, Rep. Sri Lanka
Cape Verde Latvia Swaziland
Chad Lesotho Sweden
Chile Lithuania Switzerland
China Macao SAR, China Syrian Arab Republic
Congo, Rep. Macedonia, FYR Tanzania
Costa Rica Madagascar Thailand
Croatia Malaysia Trinidad and Tobago
Cyprus Malta Uganda
Czech Republic Mauritania Ukraine
Denmark Mauritius United Kingdom
Dominican Republic Mexico United States
Ecuador Moldova Uruguay
Egypt, Arab Rep. Morocco Venezuela, RB
Equatorial Guinea Myanmar Vietnam
Estonia Namibia Yemen, Rep.
Ethiopia Netherlands Zambia
Student no: 620029286 48
9.3 Panel-89 countries
Albania Gabon Panama
Algeria Gambia, The Papua New Guinea
Argentina Germany Paraguay
Armenia Greece Peru
Australia Guatemala Philippines
Bahamas, The Hong Kong SAR, China Poland
Bangladesh Hungary Romania
Barbados Iceland Russian Federation
Belarus India Rwanda
Belgium Indonesia Singapore
Belize Israel Slovak Republic
Bolivia Italy Slovenia
Botswana Japan South Africa
Bulgaria Jordan Spain
Cameroon Kenya Sri Lanka
Canada Korea, Rep. Swaziland
Cape Verde Latvia Sweden
Chad Lesotho Switzerland
China Lithuania Syrian Arab Republic
Congo, Rep. Macao SAR, China Tanzania
Costa Rica Macedonia, FYR Thailand
Cyprus Madagascar Trinidad and Tobago
Czech Republic Malaysia Uganda
Denmark Malta Ukraine
Dominican Republic Mauritius United Kingdom
Ecuador Mexico United States
Egypt, Arab Rep. Morocco Uruguay
Ethiopia Myanmar Yemen, Rep.
Finland Netherlands Zambia
France Norway
9.4 Panel-32 countries
Algeria Azerbaijan Bangladesh Cyprus Egypt, Arab Rep. Ethiopia Gambia, The Indonesia Iran, Islamic Rep. Israel Jordan
Kazakhstan Kenya Malaysia Mauritius Pakistan Philippines Russian Federation Senegal Singapore South Africa Sri Lanka
Sudan Switzerland Syrian Arab Republic Tanzania Thailand Tunisia Turkey Uganda United Kingdom United States
Student no: 620029286 49
9.5 Panel-23 countries
Algeria Bangladesh Cyprus Egypt, Arab Rep. Ethiopia Gambia, The Indonesia Israel Jordan Kenya Malaysia Mauritius
Philippines Singapore South Africa Sri Lanka Switzerland Syrian Arab Republic Tanzania Thailand Uganda United Kingdom
United States
Student no: 620029286 50
10. Glossary
Gharar: an element of Uncertainty
Maysir: an element of Speculation
Musharakah: A joint partnership contract with profit/loss sharing agreements instead
of interest bearing loan contracts.
Quran: The Islam Recitation.
Riba: unjust gains in trade or business: usually synonymous with interest
Sharia: The rules and underlying principles of Islamic law.
Sunnah: Usual practices of Islam that was taught by Prophet Muhammad (PBUH)
Student no: 620029286 51
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