Instructional Clarity: The Effect of Bilingualism and Instructor's Preparation

Teacher clarity, bilingualism and preparation 1

Instructional Clarity: The Effect of Bilingualism and Instructor's

Preparation .

Rasool Noghabi and Elzbieta B. Slawinski

The University of Calgary

Rasool Kord Noghabi currently Bu-Ali Sina University, Hamedan Iran

Contact: Rasool Noghabi at Bu-Ali Sina University at Hamadan,

Iran,


E-mail: nogha5@ yahoo. com

Acknowledgment : Authors are very grateful to Ms. Ivy Huynh for

her contribution as a coder of lectures.


Abstract

The study focused on bilingualism and preparation of teachers that

affected the teacher’s clarity. Twenty monolingual and bilingual

participants of various preparation, in the first phase of the

study, were randomly assigned to two groups: high and low

preparation. Participants read the same lecture and presented it a

week later. Two independent coders analyzed the lectures against

the Vagueness Terms Checklist. Eighty participants in the second

phase were randomly assigned to four lecturing conditions. The

tape-recorded lectures, chosen in the first phase, were presented

to junior undergraduate students. Students rated the lecture on an

11-item response form. Results of this study were analyzed using a

two-way analysis of variance and post-test design. Bilingualism

showed significant statistical results.


Introduction

Teacher’s talk is an expected and extensive routine of classroom life. Many aspects of Instructional clarity as a preparation to the lecture were addressed already by many authors (e.g., Gliessman, Pugh, Brown, Archer, and Snyder, 1989; Metclaf, 1992; Hiller, 1971; Rogien, 1995; Rosenshine and Furst, 1971). In spite instructional clarity having waned from research studies in recent years, it is still alive with respect to bilingual instructions and their outcomes. The work is going in the American and World Universities with respect to the training of bilingual’s teacher and it contact with students. Bilingualism can affect the instructor clarity, because knowledge of English among bilinguals is usually not the same as that of the monolingual (English) instructors (e.g, Best, McRoberts, andGoodal, 2001; Snow, 1993; Strange, Yamada, Kubo, Trent, and Niski, 2001). In order to provide students with correctly spoken English phonemes bilinguals have to retrieve important information from their auditory cortex and integrate them in their cognitive areas (e.g. Slawinski, 1999; Slawinski and MacNeil, 1994). The age at which Englishis learned by bilinguals and intensity of immersion into English are vital contributing factors to perception, articulation, and an understanding of English speech (e.g. Slawinski, 1999, Slawinski and Wiigs, 1999). Speakers of morethan one language are switching their languages (codes) during communication. Code switching has been viewed as a strategy to compensate for insufficient language proficiency(Heredia and Altariba, 2001). Sidhu and Slawinski (2004) as well Xie and Slawinski (2005) indicate that proficient (competent) bilinguals demonstrate knowledge for the linguistic principles that allow grammatical words' strings and prohibit ungrammatical words' sequences for code switching.

Student must process as many as 25 to 30 phonetic segments per second

(the average conversation rate of 125 to 180 words per minute occurs


among speakers). Thus, phonemes spoken by bilingual instructors who

also conserve an intonation contour of the native language could be

misunderstood by students (e.g.,Archibald, 1998; Snow, 1993).

There is no one-to-one correspondence between the speech sounds

distinguished in a language and their acoustical properties. In spite

of this, listeners are able to assign specific labels (e.g., the

phoneme names of sounds) to different acoustical values on a continuum

of speech sounds. As such, the perception of speech sounds is

described as being categorical in nature and includes a phoneme

boundary between categories of speech sounds (Liberman, Harris,

Hoffman, & Griffith, 1957). However, the fact that different languages

have different phoneme boundaries leads to questions about how the

categorization of phonemes is affected by an individual’s fluency in

more than one language (e.g., Flege 1988; Slawinski and Wiigs 1999).

Phonological representation of bilingual speakers led to development

of two major hypotheses 1. Bilingual speakers may adopt intermediate

articulation (production) and perceptual values as a type of

compromise between the phonemic boundaries of their first language and

second language (e.g., Flege and Eefting, 1987b). 2. Bilingual

individuals develop two separate phonetic systems (e.g, Flege, 1988). To


date, research on the production of similar sounds to native speakers

by bilingual participants has suggested that differences in phoneme in

the two languages may change as a function of proficiency (e,g.; Flege

and Eefting, 1987a; Sidhu and Slawinski, 2005). However, there is

some uncertainty as to the direction of this change.

When Rosenshine and Furst (1971) reviewed the studies of process-

product variables, they found that the teacher's clarity became a very

important characteristic of a teacher. Hiller (1971) reported that

knowledge of subject matter could affect a teacher’s clarity and

especially her/his usage of vagueness terms. It was stated that the

vagueness terms are an internal stimuli condition principally

determined by a performer’s instant command of knowledge, by his/her

motivation to communicate, and by his/her own evaluation of imperfect

success. In the model of conceptual vagueness, he hypothesized that

there exists interrelationships among vagueness terms, knowledge,

emotion, and intended style of expression.

Hiller (1968) divided vagueness terms into eight categories of

impreciseness that were followed by Smith and Cotton (1980) (see

Appendix A): 1. Ambiguous designation 2. Approximation;


3.“Bluffing”and Recovery; 4. Error admission; 5. Indeterminate

quantification; 6. Multiplicity; 7. Possibility; 8. Probability.

The teacher’s clarity can be quantified objectively by low-inference

descriptors. Several researchers (e.g., Hiller, Fisher, and Kaess,

1969; Hines, Cruickshank, and Kennedy, 1985; Land 1981; Land, 1987;

Smith, 1977; Smith, 1985a; Smith, 1985b; Smith, 1987; Smith and

Bramblett, 1981; Smith and Cotton, 1980; Smith and Land, 1980; Smith

and Land, 1981) have reported low-inference descriptors, associated

with teacher’s behaviors. In these studies, two low-inference

descriptors of the teacher’s clarity such as a usage of vagueness

terms and utterances that included “Ah, Uh & Um" are described. Based

on observations of teachers in natural classroom settings, the teacher

averaged from two to five vagueness terms per minute of her/his talk

(Smith and Land, 1981). Mean of 2.18 vagueness terms per minute of

teacher talk with 40 percent of the teachers averaging between 2.5 and

4.0 such terms per minute was reported (Smith, 1977).

Another low-inference variable is the use by speakers sounds “Uh”

“Ah” & “Um”. These sounds were labeled Verbal Fluency (Hiller, Fisher,

and Kaess, 1969). A significant positive correlation between teacher’s

verbal fluency and student’s achievement was reported. For example,


the usage of utterance “Uh” had a significant effect on the student’s

achievement and perception (Land, 1981). However, Smith in his

studies reported a lack of significant correlation between an

occurrence of the teacher’s “Uhs” and student’s achievement.

It was shown that student perception of the teacher's clarity mediates

strongly. The effect of the teacher's clarity on student satisfaction

(path coefficient = 0.51, p< 0.001), and the effect of teacher's

clarity on a student's achievement (path coefficient = 0.13), as well

as the percent of variance in student perception and achievement can

be accounted for by various teacher clarity variables, as well as the

percent of variance in achievement (Land, 1987). However, the percent

of variance accounted for by clarity was greater for perception than

for achievement.

Therefore the purpose of this research was to determine the effects

of:

1. bilingualism on two low-inference behaviors of instructor clarity

(vagueness terms and utterance of “Ah”, “Uh” & “Um”),

2. bilingualism on student perception of the presentation.

3.preparation level on two low-inference behavior of instructor

clarity (vagueness terms and utterance of “Ah”, “Uh” & “Um”)


4. preparation level of instructor on student perception of the

instructional clarity.

Method

Participants

Twenty senior undergraduate female students ranging in age from 20 to

40 years with a median age of 22.5 years from the Department of

Psychology at the University of Calgary participated in the first

Experiment (first phase of the study:10 bilingual and 10 monolingual).

Participants in the first experiment were randomly assigned to one of

two groups, high-preparation and low-preparation (n = 10). A

preparation of teachers led to the Experiment 2. Experiment 2: Each

group included 5 bilinguals and 5 monolinguals. In the third

experiment (second phase of the study) 80 junior undergraduate

students (more than 91% female) from the Psychology department

participated. Participants in the third experiment were randomly

assigned to one of four conditions: bilingual teacher and high-

preparation; bilingual teacher and low-preparation; monolingual

teacher and high-preparation; monolingual teacher and low-preparation

(n = 20 participants per each group). All students reported very

good hearing and a lack of any neurological problems.


Procedure

Each participant in the experiment had an opportunity to familiarize

with the same lecture’s topic by a maximum of 45 minutes. After a week

the lecture was presented by them to no existing students and their

lecturing performance was recorded using Sony Electret condenser

microphone (ECM-270), “Revox” tape-recorder (B710 MKII), and anechoic

chamber (IAC). In the experiment 2 participants were using the same

procedure as in the experiment 1. The high-preparation group had 10

minutes to review the lecture plus 5 minutes to study the outline of

lecture before the lecturing. Time for the low-preparation group was 2

minutes to review the lecture and 1 minute to study its outline.

Participants in both treatments were allowed to look at the lecture’s

outline as they were teaching.

In the third experiment the 20 tape-recorded lectures were transcribed

and analyzed by two independent coders against Hiller’s vagueness term

dictionary (Hiller, 1968) and the Vagueness Terms Checklist.

Percentage of agreement (reliability) between two coders was checked

on the total number of identification made in quantifying two

variables (vagueness terms, utterances of “Ah, Uh and Um”). The

reliability for vagueness terms was .864 and for utterances of “Ah, Uh


and Um” was .962. Two levels of bilingualism (Experiment 1) and two

levels of the preparation (Experiment 2) composed four experimental

groups. One lecture from each group was selected for a use in the

third experiment. Criterion for a lecture’s selection was as a closest

value of a lecturer to the mean value of vagueness terms used by

members of a particular group.

In the Experiment 3, the selected lectures (two levels of

bilingualism and two levels of the preparation) were presented to

junior undergraduate students. They composed four experimental groups.

After the listening to tapes, participants in all groups of this

experiment rated the lecture on an 11-item lecture response form

(Appendix B).


Statistics:

In the first phase of the study, there were two independent variables:

bilingualism (bilingual and monolingual) and preparation (high versus

low). Two 2 * 2 analysis of variance were performed on the measures

of vagueness terms and utterances of Ah, Uh & Um. In the second phase

of the study a randomized, post-test design was used.

The first phase of the study served as a choice of speakers.

Evaluation of the first phase was based on a number of vagueness terms

and utterances of “Au, Uh & Um” used by lecturers. The second phase of

this study was designed to evaluate by students these speakers as

potential teachers. Thus, the second phase was evaluating student's

perception.

Results

A 2 * 2 analysis of variance was performed on the measures of

vagueness terms, utterances of Ah, Uh & Um, and the lesson evaluation

scores. The means and standard deviations of these scores are shown in

table 1. The results of the analysis of the ratio of vagueness terms

to total of words indicated that the main effect due to bilingualism

was significant F (1,16) = 3.778; p< 0.07. However, the main effects


due to preparation level and the interaction between bilingualism and

preparation were not significant.

Insert table 1 about here

Similar results were obtained for the ratio of vagueness terms to

total of time. The main effect due to bilingualism was significant F

(1,16) = 5.181; p< 0.03. However, the main effect due to preparation

level was not significant. In addition, the interaction between

bilingualism and preparation was not significant.

There were no significant results for ratio of utterances of Ah, Uh &

Um to total of words. However, for ratio of utterances of Ah, Uh & Um

to total of time, the main effect due to bilingualism F (1,16) =

3.888; P< 0.066 and the interaction between bilingualism and

preparation F (1,16) = 3.549; P< 0.078 were close to significant. The

ratio of utterances of Ah, Uh & Um to total of time for monolingual

lecturers in the high-preparation group was higher than that for the

monolingual lecturers in the low-preparation group, however, for

bilingual lecturers in the high-preparation group was lower than that

for bilingual lecturers in the low-preparation group.

The results of the analysis of the lecture evaluation scores are

presented in table 2. These scores resulted from totaling the scores


for all 11 items of lecture evaluation. The main effect due to

preparation level was significant in favor of the high-preparation

group, F (1, 76) = 8.437, p < .005. The main effect due to

bilingualism and also interaction between bilingualism and preparation

were not significant.

Insert table 2 about here

Cohen (1981) noted that pooling individual item ratings to obtain an

overall rating gives only a crude estimate of student evaluation of

lecture’s effectiveness. Therefore, each of 11 items of lecture

evaluation was treated as a dependent variable and 2*2 analysis of

variance was conducted. The bilingualism variable was significant in

favor of monolingual lecturers for items such as “d” (coherent), “h”

(speech easy to understand) and “j” (very clear lesson). The

preparation level variable was significant for lecturers in high

preparation group for list’s items such as “b” (decisive), “c”

(explains fully), “e” (well prepared), “f” (confident), “g” (well

organized) and “k” (clear and understandable explanation).

Bilingualism nor preparation were significant for items “a” (precise)

and “i” (speech soothing). Only item “h” (speech easy to understand)


indicated a significant interaction between bilingualism and

preparation level.

There was no significant relationship between student ratings and

gender as well as between student ratings and studying in the first or

second year.

Discussion

The results of the study indicate a significant relationship between

bilingualism and use of vagueness terms and utterances of Ah, Uh & Um

in a lecture. Interestingly, these relations were in favor of

bilingual lecturers. Therefore, the monolingual lecturers used

vagueness terms and utterances of Ah, Uh & Um more often than

bilingual lecturers. Knowledge of language can affect tusage of

vagueness terms.

The present study selected the instructor’s preparation as another

independent variable that can affect the usage of vagueness terms. The

result of this research about effect of preparation level on vagueness

supported Hiller (1971). The findings of studies about teacher’s

preparation till now have not been consistent (Hiller 1971, Hiller &

Ultman, 1973, Smith and Bramblett, 1981). In order to show effect of

preparation in the present study maybe 10 minutes for preparation


after one week has not been enough long for participants in the high-

preparation group. Participants, who were allowed to look at the

outline of lecture might attenuate treatment effects.

The results of the present study suggest that junior undergraduate

students are able to distinguish between well prepared and not well

prepared teachers. The similar finding reported by Smith (1985 a),

Smith (1985b), and Land (1981), that student’s perceived clarity may

be as important as actual teacher clarity.

Another observation in this study is that the bilingual students in

this “laboratory setting” used a lower mean frequency of vagueness

terms (1.96 per min in high-preparation and 2.94 per min in low-

preparation group) than mean frequencies reported in research

conducted in natural settings. Such research (e.g., Smith and Land,

1981) indicated means of three to five vagueness terms per minute.

However, the monolingual students used the same number of vagueness

terms in natural settings (4.18 per min for monolingual lecturers in

high-preparation and 3.71 per min in low-preparation group).

A suggestion resulting from results of this study is that teacher

trainers and teacher evaluators should focus on teacher behaviors that

can be quantified objectively. Examples of these behaviors should be


considered, especially for monolingual students, such as the usage of

vagueness terms or utterances of Ah, Uh & Um (Smith, 1985).


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Table 1: The means and standard deviations of measures of vagueness

terms

Bilingualism Preparation 1 2

3 4

Monolingual High Mean .0347

4.18 .0580 7.228

N 5 5 5

5

SD .0126 1.536 .0370

4.986

Low Mean .0328 3.706

.0486 4.825

N 5 5

5 5

SD .0083 1.521

.0461 3.835


Total Mean .0337

3.943 .0533 6.027

N 10 10 10

10

SD .0101 1.463 .0397

4.381

Bilingual High Mean .0186

1.958 .0143 1.545

N 5 5

5 5

SD .0097 1.074

.0097 1.175

Low Mean .03

2.943 .0507 4.695

N 5 5

5 5

SD .0121 1.662

.0145 1.581


Total Mean .0243

2.451 .0325 3.120

N 10 10

10 10

SD .012

1.418 .023 2.117

Total High Mean .0266

3.069 .0362 4.387

N 10 10

10 10

SD .0136 1.712

.0243 4.542

Low Mean .0314

3.324 .0496 4.760

N 10 10

10 10


SD .0098 1.555

.0326 2.766

Total Mean .029 3.197

.0429 4.573

N 20 20

20 20

SD .0118 1.597

.0333 3.665

The ratio of vagueness terms to total of words

The ratio of vagueness terms to total of time

The ratio of utterances of Ah, Uh & Um to total of words

The ratio of utterances of Ah, Uh & Um to total of time


Table 2: The Means and standard deviations of lecture evaluation scores

Bilingualism Preparation N Mean

SD

Monolingual High 20 30.7

6.674

Low 20

25.2 8.256

Total 40

27.95 7.916

Bilingual High 20

27.25 7.397

Low 20

23.35 6.483

Total 40

25.3 7.144


Total High 40

28.95 7.17

Low 40

24.27 7.387

Total 80

26.625 7.609


Appendix A: Vagueness terms and frequency of their occurrence

Category Total

frequency of occurrence

1. Ambiguous designation 6

Condition (1), somehow (1), somewhere (3), thing (1)

2. Approximation 8

About (2), a little (2), just about (1), somewhat(1), sort of (2)

3. “Bluffing” and Recovery 55

Actually (7), and so forth (1), and so on (1), anyway (5),

As you know (5), in a nutshell (1), in essence (3), in fact (4),

in other words (2),of course (10), or whatever (2),

to make a long story short (2),you know (7), you see (5)

4. Error admission 4

Excuse me (1), I’m sorry (1), I guess (2)

5. Indeterminate quantification

14

A bunch (1), a couple (4), a few (1), some (3), various (5)

6. Multiplicity 6


Kind(s) of (2), type(s) of (4)

7. Possibility 18

Chances are (1), could be (1), may (1), maybe (4), might (5),

perhaps (3), seems (3)

8. Probability 9

Generally (2), in general (1), often (1), ordinarily (2), probably (1),

usually (2)

Total use of vagueness terms

120

Note: Numbers in parentheses refer to frequencies of occurrences of

terms in the lesson containing vagueness terms in Smith and Cotton’s

Research (1980).


Appendix B: Lecture Response Form

What did you think of the teaching?

a. precise 5* 4 3 2

1 imprecise

b. decisive 5 4 3 2

1 indecisive

c. explains fully 5 4 3 2

1 does not explain fully

d. coherent 5 4 3 2

1 incoherent

e. well prepared 5 4 3 2

1 not well prepared


f. confident 5 4 3 2

1 not confident

g. well organized 5 4 3 2

1 not well organized

h. speech easy to 5 4 3 2

1 speech not easy

understand

to understand

i. speech soothing 5 4 3 2

1 speech irritating

j. very clear 5 4 3 2

1 lecture not clear

lecture

at all


k. clear and 5 4 3 2

1 confusing explanation

understandable

explanation

*Indicating the scoring value

Instructional Clarity: The Effect of Bilingualism and Instructor's Preparation

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