Detecting and forecasting economic regimes in multi-agent automated exchanges
The Pychology of Economic Forecasting
Transcript of The Pychology of Economic Forecasting
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THE PSYCHOLOGY OF ECONOMIC FORECASTING *
Published as: Wennberg, K. & Nykvist, B. (2007). The Psychology of Economic
Forecasting. Global Business and Economics Review. 9(2): 211-226.
Karl Wennberg
Center for Entrepreneurship and Business Creation
Stockholm School of Economics
P.O. Box 6501
SE-113 83 Stockholm, Sweden
Fax: +46-(0)8-318 186
E-mail: [email protected]
Björn Nykvist
Stockholm Environmental Institute
P.O. Box 2142
SE-103 14 Stockholm, Sweden
Fax: +46-(0)8-723 0348
E-mail: [email protected]
Abstract: Is the imprecision of economic forecasts due to the judgments
of ‘biased’ decision makers? This study explores decision-making
among expert forecasters in Sweden using semi-structured interviews.
The results indicate that forecasters’ decision processes are
characterized by intuitive as well as calculating reasoning, gradually
adopting mental models and conflicting goals. While forecasters make
judgments that are non-optimal in terms of minimizing forecasting
errors, these are not necessarily biased but can be described as
ecologically rational decisions. The results indicate that behavioral
forecasting research would benefit from taking into account the specific
decision-making environment in which forecasters operate.
* We are grateful for valuable comments from Lisbeth Hedelin and two
anonymous referees on earlier versions of this paper. Remaining flaws
are entirely our own.
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INTRODUCTION
Macro economic forecasts exhibit strong influence on political and financial
decisions made by states, local authorities and private corporations alike. The general
accuracy of forecasts has however been found to be quite low, which have lead
management writers such as Mintzberg (1994) and Sherden (1998) to question the value
of economics forecasting.
Prior research on behavioral aspects of forecasting (e.g. Ash, Smyth, & Heravi,
1998; Ashley, 1988; Löffler, 1998; Pons, 2000) have tended to focus on ‘biased’
judgments, neglecting the actual motives and decision-making process taking place
among professional forecasters. In the current study we seek to challenge behavioral
forecasting research to move beyond merely determining under what circumstances
forecasters make non-optimal judgments. Drawing upon the ‘naturalistic’ strand of
judgment and decision making, we explore the decision-making process among the ten
largest forecasting institutes in Sweden. In-depth interviews with ten expert forecasters
reveal that their decision-making process is a joint process of deliberate and intuitive
thinking, characterized by gradually adopting mental models along with conflicting
motives and demands. These findings show that while forecasters make judgments that
are non-optimal in terms of minimizing forecasting errors, these are not necessarily
‘biased’ but more suitably described as ‘ecologically rational’ forecasting strategies
(Gigerenzer, Todd, & the ABC Research Group, 1999). One such strategy that we
identified was a tendency not to deviate too much from the consensus, leading to
herding behavior among forecasters. This was justified by the forecasters as the possible
benefits of ‘becoming the sole winner’ being outweighed by the risk of ‘becoming the
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sole faulty outlier’, indicating that the decision-making setting of forecasters includes
multiple, partly conflicting goals.
An implication of this study is that research on forecasters’ judgment and
decision-making need to consider the specific institutional environment in which
forecasters operate. The study also points to some avenues for future research.
Macro economic forecasts
Evaluations of GNP forecasts reveal that precision is often poor. Studies of
international GNP forecasts such as OECD’s (Ash, Smyth, & Heravi 1998; Blix et. al,
2001; Öller, & Barot, 2000; Pons, 2000), as well as growth forecasts for Sweden (Barot,
2003; Blix, Friberg, & Åkerlind, 2002; Montgomery, 2000) demonstrate the difficulties
in making accurate forecasts. Some scholars suggest that simple linear models perform
equally accurate or better than individual forecasts (Grove & Meehl, 1996; for a general
discussion see Dawes, Faust, & Meehl, 1993). In a number of cases, forecast accuracy
has proven inferior to the so-called naive forecast (Ash et al., 1998; Ashley, 1988; Öller
& Barot, 2000), i.e. the forecast equivalent to last year’s outcome.
Considerable effort has been directed to scrutinizing past forecast statistics, using
these to draw inferences about the behavior of forecasters (Ash et al., 1998; Laster,
Bennett, & Sun, 1999; Löffler, 1998) that may explain the lack of forecast accuracy.
Most of these studies have used record on past forecasts and outcomes to draw
inferences about forecaster’s behavior. From the perspective of naturalistic decision
making, this approach neglects the role of forecasting as a specific type of expertise
(Shanteau, 1995). Also, it fails to recognize the influence of the particular decision-
making setting (Klein, 1994). We therefore see a need for studies investigating
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forecasters within their own operating environment. As suggested by Montgomery
(2000), we intend to explore the decision-making process among expert forecasters
through an in-depth qualitative study. Before doing so, we provide an overview of the
forecasting industry in Sweden. We will outline the overall accuracy of forecasts from
1993 – 2001 to provide a background for the qualitative study.
This study focuses on GNP forecasts in Sweden. Despite being a relatively small
country, Sweden has several forecasting institutes such as governmental institutes,
commercial banks, as well as labor and industrial confederations. This study
concentrates on the ten largest forecasting institutes (Figure 1). These institutes present
forecasts both for the current and for the coming year. This study focuses mainly on
“one year ahead forecasts”, that is, GNP forecasts presented in the autumn for the
coming year.
--------------------------------
Insert Figure 1 about here
---------------------------------
As can bee seen in Figure 1, large deviations between forecasted and actual GNP
existed during the period 1993-2002. To briefly examine the accuracy of forecasts we
measured the Mean Errors (ME) for the ten forecasting institutes during the period. ME
measures systemic errors (i.e. whether an institute on average are overly positive or
negative) through a simple arithmetic mean of the forecast errors (Pt - At). ME errors for
the individual institutes are presented in Figure 2, the magnitude of the total mean error
for the institutes is -.20. This shows that the ten forecasting institutes had a tendency to
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underestimate GNP growth rate during the period 1994-2002, t(89) = -2.42, p < .05.
Thus forecasting institutes seem to exhibit a negative bias in their forecast decisions,
which is coherent with the findings of a contemporary Swedish study (Barot, 2003) as
well as studies of Chilean (Chumacero, 2001) and OECD forecasts (Blix, et al., 2001).
But what are the actual decisions that lie beneath such erroneous forecast judgments?
--------------------------------
Insert Figure 2 about here
---------------------------------
The apparent lack of forecast accuracy may lead to doubts over the actual value of
GNP forecast. Research on expert judgments has shown that simple linear models often
predict the future more accurately than experts do (Dawes, Faust, & Meehl, 1993;
Grove & Meehl 1996). Might there be other reasons for issuing growth forecasts than to
accurately predict future growth rates? Furthermore, are the systematic errors indicated
in Figure 2 due to deliberate strategies as suggested by Laster et al. (1999), or result
from cognitive errors as suggested by Löffler (1998)? To untangle these questions, this
study will investigate the decision-making process among expert forecasters, drawing
upon theories from the judgment and decision-making (JDM) literature.
Expert decision-making: from bias and heuristics to ecological rationality?
Research on judgment and decision-making (JDM) is a vigorous field that has
attracted the attention of several disciplines apart from cognitive psychology such as
economics, medicine, political science, marketing and management science. The field
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has to some extent been dominated by the ‘bias and heuristics’ program that emphasize
the search for cognitive mechanisms that affect people’s judgments in non-optimal ways
(Tversky & Kahneman, 1974). “Heuristics” are processes that people use in order to
design a representation of the world so as to help them to make quicker and more
efficient decisions, a ‘decision rule of thumb’, so to speak. Tversky and Kahneman
argued that these heuristics frequently lead people to systematically deviate from what
can be considered an optimal decision based on laws of probability. Although easy and
efficient, such heuristics often leads to “biases” in the sense that relevant but
contradicting information may be ignored.
Since the bias and heuristics view has received increasing interest in economics
and management science, it is interesting to note that psychologists have for a long time
debated the general validity and usefulness of the approach. A number of issues have
been raised: First, it has been argued that the bias and heuristics studies have assumed
inappropriate normative models of behavior (Birnbaum, 1983; Gigerenzer, 1991).
According to Hogarth (1981), such normative assumptions have lead to
overgeneralization of results and a general “failure to specify conditions under which
people do or do not perform well” (1981:197). Second, replicating studies has called
attention to that fact the situations presented in the most-cited studies from the bias and
heuristics program are linguistically and pragmatically unclear to subjects and
consequently not very useful in assessing individuals’ decision-making abilities
(Gigerenzer, Hell & Blank, 1988). Third, the bias and heuristics approach have
exclusively focused on groups’ central tendencies which has led to difficulties in
reconciling the variability that people display on specific tasks (Stanovich, 1999).
Fourth and possibly most relevant for economics and management science: because the
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normative tasks used in the bias and heuristics studies generally presents null
hypotheses of rational behavior as precise point estimates, it is easy to produce large-
sample directional violations in either direction (Krueger, 1998). A consequence of
these problems is that the bias and heuristics approach, albeit successfully finding a
multitude of human reasoning errors, has more seldom been able to explain why or how
human decision makers make use of heuristics (Hertwig & Todd, 2000).
A strand of the JDM literature has focused instead on the importance of studying
decision makers as they actually operate in real-world or ‘naturalistic’ settings (Klein et
al., 1993). This research has helped to improve our understanding of decision makers’
use of heuristics as ‘ecologically rational’, making adequate decisions by exploiting the
structure of information in their environment (Gigerenzer et al., 1999). Viewing
decision makers as ecologically rational would then imply that practical reasoning
mechanisms should be judged by whether or not they solve the problems they are
confronted with.
In this study we seek to investigate the decision-making process, including
reasoning, problem framing and the motives of expert forecasts. A key concern is to
investigate forecasters within their own operating environment. Orasanu and Connolly
(1993) argue that the richness, dynamism, and uncertainty of a natural context involves
a setting characterized by (1) ill-structured problems, (2) uncertain, dynamic
environments, (3) shifting, ill-defined, competing goals, (4) action–feedback loops, and
(5) high stakes associated with decisions. These characteristics correspond fairly well to
the settings of macro economic forecasting (e.g. Sherden, 1998). In this study we
therefore take a naturalistic perspective, seeking to explore and discern the vital
components of forecasters’ decision processes.
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METHOD
Since we want to provide a detailed account of the decision-making and reasoning
of expert forecasters in their own environment, we use an in-depth qualitative approach
(Klein, 1994). We expected several of the topics of interest to our study to be
controversial in the forecast community (Sherden, 1998). Personal interviews rather
than questionnaires were deemed appropriate to elicit more valid responses (Huberman
& Miles, 1994). We used a semi-structured interview guide with a fixed set of questions
but with room for elaboration and follow-ups. The questions related to (i) the decision
process leading to a forecast, (ii) perception and gathering of information, (iii)
evaluations of past forecasts, and (iv) the existence of ‘rules of thumb’ and intuitive
thinking. The full interview guide can be found in appendix A.
One expert from each of the ten largest forecasting institutes in Sweden was
interviewed. Since the goal of an exploratory study of this kind is to create a base for in-
depth and more complete understanding of a specific phenomenon (Huberman & Miles,
1994) the selection of organizations and individuals to be studied was neither accidental
nor random in statistical terms. The interviewees were chosen for “being the most
knowledgeable in forecasting” at that particular institute, i.e. a judgment based
sampling. Six of the interviewees were directors or managers officially responsible for
GNP forecasts at their forecasting institutes. The remaining four were senior forecast
experts with many years of experience in their field. This selection roughly covers the
population of larger forecasting institutes in Sweden but includes only one expert
forecaster per institute. The participants were interviewed in their own facilities by both
authors using the described semi-structured interview guide. The interviews were tape-
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recorded and lasted for approximately 90 minutes. After transcribing the interview in
full they were organized in spreadsheets according to a person*question matrix. This
approach facilitated analysis of the interview data through search for common themes
and patterns (Coffey & Atkinson, 1996). Statements and verbal nuances could thus be
refined and particular statements used to exemplify common responses were included in
the study’s results. When quantifying the number of respondents for a specific statement
we consequently use the same wordings in the text: “a few” expert should be read as
two-three experts, "several” experts as four-five experts, “most” experts as six-seven
and “almost all” experts as eight or more out of the ten respondents.
RESULTS
The result from our study is presented in order of the main results: (1) intuitive
decision-making, (2) formal and informal decision models, (3) forecast evaluation and
feedback, (4) accuracy and credibility as forecasting goals, (5) market segmentation of
economic forecasts, (6) inertia in the decision-making process. All quotations were
translated from Swedish by a professional translator.
Intuitive decision-making
The interviews clearly indicate that the expert forecasters in this study believe it is
impossible to take into account all available information when forming a forecast
judgment. One forecaster explained this as:
”It is impossible to make sense of the enormous amount of information and at the
same time consider all important aspectsin a way that is formally violable. Instead we
weigh the input on an intuitive basis.”
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Specifically, the forecasters seem to rely on certain rules of thumb (heuristics) to
identify key indicators to guide judgment of macro economic conditions. One such
heuristic that could be spotted was that all the expert forecasters interviewed seem to
have one or a few favorite “key variables”, or cues, that they observe in order to foresee
macro economic turning points. Two cues mentioned include changes in net exports and
the quarterly survey of future demand among purchasing managers. In addition, almost
all of the experts indicated that intuitive reasoning or “gut feeling” is a vital part of the
forecasting process:
”When it comes to forecasts I believe that, at the end of the day, it is gut-feeling that
determines the outcome…A comprehensive view is in fact not to be too careful or
formal. To be able to explain things intuitively is more or less what counts.”
”At all times, as with all forecasters, there is a continuous process in my head. This
means that I never begin with a blank sheet.”
The fact that a final forecast decision is to some extent based on prior beliefs and
intuition is further indicated by the answers to our question regarding how the overall
economic climate affects how expert forecasters work:
”Yes, it affects us, after all we are not robots.”
”There are, of course, people who do not want to think in these terms, as one has ones
own opinion of what these connections are like…There are those who are no suitable
for this kind of work. There are visionaries and, if I may say so, calculator-happy
people. But even if the map deviates from reality you must stick to the map.”
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When discussing various aspects of intuition and experience with the ten expert
forecasters several of them put forward an interesting description of forecasting experts
as being a close-knit community:
”There is, of course, a ‘nerdish’ element. By this I mean that a certainjargon exists
and no matter how you look at it, it all comes down to the specific knowledge and
ideas of the individual or the group. Some things are set in stone, that is for sure”
”But what you were asking is perhaps whether we get caught up in the clamor, and
that is impossible to answer, but I certainly believe this to be the case.”
Formal and informal decision models
Another part of the interview concerned the usage of formal (econometric) models
and decision tools. Most of the respondents stated that econometric models cannot be
used to fully formalize the judgmental phase of the forecasting process. Instead, smaller
models in the form as equations formalizing a relationship between different macro
economic variables are used as leading indicators, or as consistency checks to verify the
forecaster’s line of thought:
”We do not rely merely on a single model when making forecasts; instead we use
models more or less as indicators.”
”I see models more like a consistency check on my concept of the world and the rules
of thumb that I use…you weigh [information], and this you must be able to do in your
head, you cannot have your nose completely stuck in a model.”
This indicates that the decision-making process follows an iterative process,
seldom beginning with a blank sheet but with a ‘hunch’ or a more-or-less defined idea
of how economic conditions are likely to change in the time to come. Formal
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discussions, information-gathering and analyses of large amounts of data by
econometric methods are then performed jointly as the original scenario is revisited and
changed, until a final forecast is set.
Forecast evaluations and feedback
Most institutes investigated in this study do not employ any formal evaluation
procedure. A few institutes casually evaluate their GNP forecasts against actual
outcome:
”Then I must confess that we do not adhere to a strict routine, we do this only when
we have a little time to spare.”
However, a majority of the forecasters referred to some sort of informal
evaluations in their day-to-day discussions with colleagues:
”We make no formal evaluations, but you will notice whether your concept of the
world has been entirely wrong, so in a way there is feedback, although this is
completely informal.”
The lack of feedback is not surprising, given that final GNP figures are released
one and a half years after the end of the forecasting period, i.e. almost three years after a
forecast is made. During this time, preliminary outcome figures are constantly revised.
Several forecasters explained that this is a serious problem for them:
“We’re trying to hit a moving target; one could never be sure whether we missed. And
then when you get the preliminary figures you adjust to those figures that stick in your
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mind. When the outcome figures are finally released you have already moved on and
started to think of the outcome in preliminary terms. It is difficult to change your mind
like that.”
The quote above illustrates that forecasters cannot take a preliminary measured
GNP at face value, which makes effective feedback impossible. However, we found that
the three larger forecasting institutes with more resources available conducted formal
evaluation on a regular basis. The three larger forecasting institutes also have a fair
record of forecasting accuracy. If formal evaluation contributes to this accuracy, or if
forecasting accuracy as well as the existence of evaluations are both the results of
superior resources, are however questions beyond the scope of this study.
Accuracy and credibility as forecasting goals
All experts are well aware that there are several difficulties in making accurate
forecasts. Still, they point to the fact that other goals than hundred percent forecasting
accuracy are equally important:
”I do not think that authenticity is that important. I believe that it is more important to
make an intelligible forecast which explains how [macro economic] relationships
work and which cause leads to which effect, and to present a concept of the world that
is consistent.“
”So, returning to your main question, how to make accurate GNP forecasts, then
maybe the reality is that this is not our main task.”
Several of the expert forecasters considered that the most important aspect of
forecasting is to present a reliable case or scenario. To minimize forecast errors is not
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considered as important as to deliver a consistent and interesting case given a certain set
of assumptions about the future and statement about fiscal politics etc.:
I believe that the figures must be reflected in the text. The important thing is to present
a picture of what causes what. Looking at a table, you cannot really understand what
is going on. You must build a discussion outlining how things work out, and this is
what I want to put across in our forecasts.
”As I see it, there are no forecasters who make objective forecasts in the sense that
they are true mathematical expectations; instead all forecasters produce a certain
scenario.”
Several forecasters explained that what is of main concern to their users is
whether the economic situation the coming year is going to be better or worse than the
present year. Interestingly, we found a discrepancy between the expert forecasters’
interpretations of error magnitude and our own. Most of the experts seemed to consider
the errors made rather small, given the complexity of the forecasting industry:
”If you were to organize your own finances like the national accounts, then you would
know exactly how much you had spent during a certain period of time, and you would
be aware of your assets at the beginning and the end of that period…this is what we
are trying to do, but for a whole country.”
This view seemed to stem from the fact that the expert forecaster focuses on what
the actual GNP figure will be, while researchers tend to focus on GNP growth as an
annual percentage change. This is in accordance with Shanteau’s (2001) findings that
discrepancies exist between experts and researchers in how they estimate forecasting
accuracy and decisions. According to Shanteau, experts evaluate errors as if they have
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flat loss functions for deviations from optimality, whereas researchers often operate as if
they have steep loss functions. Experts consequently tend to regard small deviations as
having minor consequences, while researchers tend to regard any deviation from
optimality as having large consequences. In other words, while experts are concerned
about avoiding big mistakes, researchers are looking for perfection.
Several of the respondents mentioned that it is perfectly possible to reach an
accurate forecast by mistaking directional changes in crucial units such as net export or
private consumption if these mistakes cancel each other out. This indicates that they
evaluate themselves according to what the ecological JDM literature would describe as
‘task performance’ evaluation, as opposed to evaluating only the accuracy of a forecast:
”You should not compare GNP forecasts against actual outcome, but instead look at
any reasons for being right or wrong. It could be worse to be right in your forecast if
you say that exports will increase and private consumption decrease and it turns out
to be the other way around, even if your whole GNP forecast has proven more or less
correct.”
The market segmentation of economic forecasts
Several of the experts stated that there are clear incentives to market a forecast
scenario as to spread a certain opinion or promote their respective institute:
”Since you want to reach the customer, you must make sure your case is interesting.”
Almost all the expert forecasters said that they believe such views also exists
among some of the other institutes. This indicates the existence of strategic biases, a
deviation from error-minimizing judgment due to some sort of conscious strategic
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behavior. Forecasters have incentives to deviate from the consensus due to competing
goals which might be difficult to reconcile: to minimize forecast errors and to obtain
publicity. These findings have been documented in prior research on forecasters in other
countries (Batchelor & Dua, 1990; Laster et al., 1999; Löffler, 1998) and could be
explained by classical theories how economic agents will respond to conflicting goals
(Jensen & Meckling, 1976). Users of forecasts might demand maximized forecast
accuracy, but since forecasting institutes in part subsist on the amount of publicity they
generate, expert forecasters try to reach a compromise between these two goals. In other
words, they have motives that sometimes lead them to deviate from what can be
considered an optimal forecast. There also seems to be a time aspect involved. Several
forecasters interviewed in this study stated that forecasts released at a later date would
probably have a higher likelihood of deviation from forecasts released by other
institutes at an earlier date:
”There is a need for profiling. Say, for example, that all [forecast institutes] have
negatively revised [their forecasts]. Then you would want to profile your forecast in a
new way that is interesting and makes the headlines. It is as if there is a segment in
the forecasting market that has not been claimed, and therefore it is tempting to claim
that segment. And if you think it’s not so much of a gamble, then you alone have the
chance of being in the right.”
This “marketing segmentation of forecasts” has been explained by Bachelor and
Dua (1990) as a way for forecasters to target a group of forecast users who fit a certain
psychographic mind-set: “Economic forecasters have therefore differentiated their
products by adopting what we labeled an ´extremist´ strategy” (p. 313). A few of the
forecasters interviewed in the current study also mentioned that a forecaster with a
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generally negative or positive economic outlook might be inclined to seek employment
at a forecasting institute renowned for its generally negative or positive forecasts.
However, none of the forecasters interviewed in this study agreed with the statement
that forecasters deviate too much from the consensus. Several interviewees indicated
that they as expert forecasters generally are too dependent on each other’s forecasts.
Most of the forecasters also expressed a desire to make bolder predictions:
”As a forecaster I would say that it is worse to be the only one in the wrong than
gainful to be the only one in the right, and in so beating all the others. Thus there is
an incentive to be careful not to deviate from the norm, and so one might be afraid of
free thinking.”
These quotes indicate that expert forecasters as a profession may have asymmetric
loss function for presenting errors. This would explain the existence of herding
behavior, which has been indicated in earlier studies of Swedish (Barot, 2003; Blix et
al., 2002) and international (Batchelor & Dua, 1991; Blix et al., 2001; Pons-Novell,
2003) forecasters.
Inertia in the decision-making process
The expert forecasters in this study seem to base their decisions on a mixture of
previous beliefs and formal modeling of the economic statistics. Most forecasters also
state that their main goal is to present a reliable ‘case’. In the JDM literature this is
referred to as ‘mental models’ (Klein, 1994). Mental models lets experts know how a
complex decision is dependent on various sub-decisions that they can perform more or
less automatically, without having to break down the decision into separate tasks. The
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concept of forecasting cases as mental models is a key for understanding the decision-
making processes of expert forecasters: The mental models, refereed to by the
forecasters as cases, somewhat reluctantly have to be redefined as new information
arrives:
”Also, you have constructed a story for yourself that you believe in, and you are not
easily persuaded that this story might be utterly wrong. Unfortunately I believe that
this is a human trait.”
“I also believe that there is some prestige in sticking to your original point of view.”
The case constitutes a continuously changing model of the current situation and
when new information arrives this model has to be adjusted according to the new
situation, which is not easily done. Instead, the expert forecasters seem prone to stick to
their case until this is proven false, introducing an inertia in the decision-making
process. The interviews however indicate that this inertial process might also have a
positive feature: Cooperation and consensus seeking among expert forecasters is more
common among the larger forecasting institutes. Here, individual’s inertia may
contribute to better forecasts for larger institutes where more forecasters have to
exchange opinions:
”I believe that a small institute has 1 to 2 key people. This means that any forecast
will be capricious in the sense that these two individuals’ ideas will be decisive.
Naturally two people at different institutes may interpret information in different
ways, or put emphasis on different things. But if there are fifty people who must agree
on a conclusion then you are bound to end up with a more concordant solution.”
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”Eventually some sort of consensus will form that is the result of some sort of
compromise…we are 20-30 people here so if any form of consensus opinion is to be
changed this will be done with a certain inertia.”
DISCUSSION AND CONCLUSIONS
In this study we have put forward that studying expert forecasters in their natural
decision-making situation provides a better understanding of the decision-making
process behind economic forecasts. Our findings point at some avenues for further
research regarding the goals, decision processes, and performance of economic
forecasters.
First, we found evidence of intuitive thinking and the use of formal models being
joint components in forecast judgments, used in an iterative process together with expert
knowledge. That intuition and gut feeling are important elements of forecasting can be
explained by Bechara and Damasio’s (2005) Somatic market hypothesis. With the
complexity and unclear patterns of a rapid market economy, cognition struggles
explicitly with figuring out a ’best’ strategy, while somatic signals help select the most
advantageous response option (Bechara & Damasio, 2005).
Second, we found indications that forecasters’ primary objective might not be to
minimize forecast error but to construct a consistent and credible ‘case’. Also,
subjective mental models in the form of forecast cases play an important role in
explaining inertia in the decision-making process when presented to contrasting
information. These mental models to some extent build on the accumulated and implicit
expert knowledge of forecasters.
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That heuristics, or cues, are used in order to foresee macro economic turning
points is also consistent with other JDM studies on financial decision making among
auditors (Shanteau, 1995) and professional stockbrokers (Slovic, 1969). Given the
exploratory nature of the study, these and other results should be seen as tentative,
indicating interesting hypothesis to be examined in future work. For example, we do not
know enough about the specific heuristics used by forecasters to determine the relative
usefulness of these compared to other types of forecasting tools such as formal
econometric models.
Our study also indicates herding behavior as a likely explanation for earlier
findings that strategic biases affect forecasters’ decision-making (Laster et. al, 1998).
However, more research is needed to determine how the effects of herding behavior and
marketing segmentation interact in shaping forecasts judgments.
In addition, expert forecasters describe their decision-making process as “too
rigid” due to mental models and ideas built around the specific scenario used in a
forecast. Similarly, Schwartz (1987) found that economic decision makers in Latin
America residing in countries with little experience of devaluation were more prone to
stick to a steady forecast long after there were clear signs of devaluation, compared to
decision makers residing in countries where devaluation was more frequent. The
forecasters in this study seem prone to believe at length in a particular case until this is
falsified, leading to a rigid decision-making process. Future research might capitalize on
these findings and investigate whether this rigidity may explain forecasters’ inability to
predict macro economic turning points.
On a more general level, the findings from this study provide an argument that
forecasters should be viewed as ‘ecological rational’ rather than ‘biased’ decision
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makers. Such a view would shed new light on prior research that has pointed to the
inaccuracy of economic forecasting. The chief implication of this study is therefore that
research on forecaster’s judgment and decision-making need to consider the specific
institutional environment in which forecasters operate.
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Figure 1. GNP forecasts and outcomes at t + 1. Data source: Statistics Sweden.
Figure 2. Mean Errors (ME) for GNP t + 1 forecasts during 1994 - 2002.
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Appendix A: Interview Guide
Decision process
Can you describe your work process when you are working towards a forecast?
-collectively?
-individually?
For whom do you publish forecasts?
Who are your customers?
How do you cooperate with them?
Information, perception, and judgmental tools
Which types of information and econometric models do you use?
How reliable do you consider this information to be?
In which ways do you use this information in the econometric models you use?
Which kind of information means most to determine the outcome of econometric models?
Perception
How do you sift through between different kinds of information?
Do you discuss how information can be interpreted in different ways?
Can you describe these discussions?
How does the general future outlook and economic climate affect the assumptions that you take in a
specific forecast? [example: now – insecurity, 1999 – boom, 1993 – bust]
Judgment
How are the routines regarding the analysis preceding a forecast decision?
When/how do you change your routines? [ex. new staff]
Would you say that there is some sort of “ideal” decision process?
How does this process look like?
Do you strive for such a process?
In what way?
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Intuitive decision making
When you enter numbers into a formal model, do you have ”a hunch” of how the result of the model will
turn out?
How would you describe the concept of ”intuition”?
Is it relevant for your forecasting?
Is it based on prior experiences? How?
Do you discuss these types of questions? How?
Decision
Who takes the final decision in calling a forecast ’ready’?
Who has professional responsibility for the forecasts that you issue?
If there are question marks or internal conflicts regarding a question that is vital for the forecast, how do
you handle this?
What is your view on the difficulties to present a reliable forecast at the same time as uncertainty is high?
What is your view on the concept of “a naive forecast”? [ A. Equal to t-1., or B: Different types of
moving averages of earlier forecasts”]
Evaluation
Do you compare the outcomes of your forecasts with that of other institutes?
Why are the forecasts so different between institutes when you all have access to almost the same data?
If a forecasts turn out to be far from the mark, what is generally the reasons?
How do you evaluate earlier forecasts?
Would it be possible to improve your decision making process in any way?
Overall process
What happens after the forecast is issued?