Stuttering, Audience Size, and the Other-Total Ratio: A Self-Attention Perspective'

BRIAN MULL EN^ Murray State University

The effect of audience size on verbal disfluences in stutterers is considered from the perspective of self-attention theory. Two secondary analyses conducted using original data from studies (Hahn, 1940; Porter, 1939) which observed the effects of audience size on stuttering, reveal an increase in stuttering as a negatively accelerating function of audience size. These results confirm the utility of the self-attention theory Other- Total Ratio in characterizing the effect of the group on the individual.

With some people solitariness is an escape not from others but from themselves. For they see in the eyes of others only a reflection of themselves.

Hoffer ( 1955, p. I 18)

Recent efforts in self-attention theory (e.g., Carver& Scheier, 1981; Diener, 1980; Mullen, 1983a) have examined how group contexts affect the indi- vidual's self-attention processes and resultant self-regulation processes. Apparently as a result of a tendency for the smaller stimulus to be seen as figure (e.g., Coren, Porac, & Ward, 1979; Koffka, 1935), members of a heterogeneous group become more self-attentive, and more concerned with standards of behavior, as the relative size of their subgroup decreases.

A simple algorithm called the Other-Total Ratio has been proposed as a means of operationalizing this effect of the group on the individual. The Other-Total Ratio is defined as the number of people in the Other subgroup divided by the sum of the number of people in the Other subgroup and the number of people in one's own Self subgroup. For example, the Other-Total Ratio for one person speaking in front of an audience of 10 other people would be (OTR = lo/ ( 10+1)) OTR = .909. Similarly, the Other-Total Ratio for five people speaking in front of an audience of one other person would be (OTR = 1 /(1+5)) OTR = .167. This Other-Total Ratio has been demonstrated

'The author would like to thank two anonymous reviewers for their helpful comments on an

2Requests for reprints should be sent to Brian Mullen, Department of Psychology, Syracuse earlier version of this manuscript.

University, Syracuse, NY 13210.

139

Journal of Applied Social Psychology, 1986,16, 2, 139-149. Copyright @ 1986 by V. H. Winston & Sons, Inc. All rights reserved.

140 BRIAN MULLEN

to accurately predict levels of self-attention (Mullen, 1.983a, Studies 1 and 2; Mullen, 1985; Mullen & Peaugh, 1986), as well as a variety of resultant social behaviors (Bechtel, 1984; Mullen, 1983a, Studies 3 through 6; Mullen, 1984; Mullen, 1983b; Mullen, 1985; Mullen & Peaugh, 1986).

The present paper reports the results of an attempt to apply this self- attention theory Other-Total Ratio approach to the effects of group contexts on stuttering. This application offers a new perspective on some of the dynamics of verbal disfluencies among stutterers and, in addition, provides a novel and realistic context within which to examine the applicability of the self-attention theory Other-Total Ratio perspective.

The study of verbal disfluencies among stutterers is important to self- attention theory, insofar as stuttering has often been conceptualized as a direct consequent of self-focused attention (e.g., Brown, 1945; Dittman & Lewellyn, 1969; Schwartz, 1976; Wicklund, 1975). This might represent a special case of the type of performance decrements that are observed to occur in other contexts as a result of exaggerated allocation of attention to one’s performance and to performance feedback (e.g., Baumeister, 1984; Carver & Scheier, 1981; Kimble & Perlmutter, 1970; Langer & Imber, 1979). This self-attention-induced performance decrement has recently been dubbed “choking” (Baumeister, 1984). Thus, self-focused attention is argued to ex- acerbate verbal disfluencies on the part of people predisposed to stuttering.

Since stuttering appears to be affected by self-attention, and since self- attention appears to be affected by group composition (as indicated by the Other-Total Ratio), it follows that stuttering should be affected by group composition, and predicted by the Other-Total Ratio. The larger audience would be assumed to increase the stutterer’s level of self-attention (as indi- cated by the increased Other-Total Ratio), and thereby exacerbate the stut- terer’s verbal disfluencies.3

Hahn’s (1940) and Porter’s (1939) analyses of the effects of audience size on stuttering provide the opportunity to subject this line of inference to empirical examination. These reports include tables of the percent of words stuttered in front of audiences of various sizes for each of the subjects included in the samples (Hahn, 1940, Table I; Porter, 1939, Table IV).

’As noted by an anonymous reviewer, this does not necessarily suggest that self-focus would increase verbal stuttering. The point of the self-attention theory Other-Total Ratio perspective is to describe and explain the effect of the group on the individual. I t so happens that verbal disfluencies among stutterers appear to be influenced by group settings and self-attention processes, whereas verbal disfluencies among nonstutterers do not appear to be so influenced. A theory of verbal disfluencies might be developed to explain the ontogeny of this difference between stutterers and nonstutterers. Such a theoretical development is beyond the scope of this paper. The present approach attempts to describe and explain how the group context affects verbal disfluencies among stutterers given their predisposition to be so affected.

STUTTERING AND THE OTR 141

As a manipulated experimental variable, audience size was of obvious importance in the original analysis of these data sets. However, there is much to be gained by a secondary analysis of the data sets: Neither report formu- lated clear expectations regarding the effects of audience size, and neither report provided statistical tests of predictions regarding the effects of audience size. Moreover, neither report offered any theoretical account for any effects which audience size may have had on stuttering. Of greatest importance is the fact that neither report took advantage of the opportunity provided by their data to examine the applicability of the Other-Total Ratio (obviously, Hahn’s, 1940, and Porter’s, 1939 efforts predated these recent developments in self-attention theory by over 40 years, and therefore cannot be blamed on that account). The purpose of the present secondary analyses of these original data is to examine the applicability of the self-attention theory Other-Total Ratio to the effects of audience size on stuttering.

Study 1 (Hahn, 1940)

The procedure of data collection is described in detail in Hahn (1940). Briefly, 52 stutterers about to attend speech correction classes read aloud 550-word passages under each of three audience conditions. The audience conditions (with their corresponding Other-Total Ratios) were: (1) alone (OTR .OO); (2) audience of one (OTR SO); and (3) audience of from five to ten (OTR = .88).4 The computation of these Other-Total Ratios is illustrated in Table 1.

For each of the 52 stutterers, the percent of words stuttered in each audience condition was regressed upon the corresponding three Other-Total Ratios, resulting in 52 regression analyses. Significant regression analyses revealing positive relationships between stuttering and Other-Total Ratios would con- firm the utility of the Other-Total Ratio in characterizing the effect of the group on the individual.5

4Since the audience was described as “ranging from five to ten,” it was reasoned that the average audience size must have been somewhere around 7.5 (i.e., (5+6+7+8+9+10)/6 = 7.5). This estimate of the audience sire for the third audience condition is patently false in any given instance. However, it is the best estimate which can be made on the basis of Hahn’s reported procedure, and does serve to capture the fundamental difference between this audience condition and the other two. Therefore, this estimate ofan audience of 7.5 was used to compute the Other-Total Ratio for the third audience condition (OTR 7.5/(7.5+1) .88).

5The regression of dependent measures on the Other-Total Ratio is the analytic approach which has been used in previous examinations of the self-attention theory Other-Total Ratio perspective(cf., Mullen, 1983a, 1983b; Mullen, 1985; Mullen, 1984; Mullen&Peaugh, 1986). The regression statistics calculated for each individual in the present analysis provide a series of independent tests of the Other-Total Ratio which are uninfluenced by individual differences in initial predisposition to stutter. For example, Hahn’s Subject 17 stuttered 1.5% ofthe words when

142 BRIAN MULLEN

Kesults

The results of the regression analyses for each of the 52 stutterers are presented in ’Table 1. Meta-analytic statistics (Mullen & Rosenthal, 1985; Rosenthal, 1980, 1983) will be used to summarize the results of these regres- sion analyses. Application of these meta-analytic statistics t o the results of the regression analyses calculated for each subject provides a means of collapsing across individual subjects and summarizing the predictive accuracy of the Other-Total Ratio for the sample as a whole. Formulae and computational procedures are detailed in the above-cited sources.

Combination. The standard normal deviate for combination of significance levels is Z 5.521764 (p = .00000001884422), indicating that the combined results of these regression analyses were unlikely to have occurred if the null hypothesis were true. This meta-analytic combination of significance levels is associated with a fail-safe number for the .05 level of significance ofN(fs .05) = 533.905052, suggesting that similar regression analyses of approximately 534 stutterers showing no effect of audience size on stuttering would be required to move the overall combined probability back to the “just significant” conven- tion o f p = .05. The mean Fisher Z for combination of effect size was Z 1.417266. This corresponds to a mean correlation coefficient o fR = 389027, a coefficient of determination of R 2 = .790369, and a mean Cohen’s stan- dardized difference between the means of d = 3.88345. Thus these regression analyses tend to produce results which are statistically significant and of strong magnitude.

Comparison. The results of combination meta-analytic techniques should always be tempered by the results of comparison meta-analytic techniques. For example, if the significance levels or the effect sizes of a body of research are significantly heterogeneous, the combination meta-analyses may be pool- ing the results from hypothesis tests that are likely to be sampled from different populations. M eta-analytic difEuse comparisons indicted whether a group of studies produced significantly heterogeneous results. The results of the diffuse comparison of significance levels (xg, = 33.929601 , p = .96849), and an estimate6 of the diffuse comparison of effect sizes (x:, = 10.5879985,~ =

alone, while Subject 21 stuttered only 0.5% of the words when alone. Nonetheless, group composition appeared to influence stuttering in the same way for these two subjects: The Other-Total Ratio predicted the effect of group composition on stuttering for these two individu- als equally accurately (in both cases, R , 9 9 9 , ~ .0115). The meta-analytic statistics which are used below to summarize these separate regression analyses provide an unbiased characterization of the preditive accuracy of the Other-Total Ratio.

6This statistic is an estimate since the actual meta-analytic xz for the diffuse test comparison of effect sizes cannot be - computed from these analyses. The formula for the computation of this x 2

(xi-, = t ( n ~ 3)(2 -2)*) requires a weighting by the same size minus 3 . Applying this conventional formula to the present analyses (where each analysis is based upon a sample sire of 3) produces

STUTTERING AND THE OTR 143

Table 1

Percent o+f Words Stuttered with Different Size Audiences, and Regression Analyses (Hahn, 1940)

Regression statistics # Selfa 1 1 1 #Otherb 0 1 7.5 OTRC .OO S O .88 R R2 F(1,l) P

1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

2.9 10.2 6.5 3.6 0.4 0.5 0.2 2. I 2.5 0.4 4.5 0.2 6.7 0.9 0.5

14.4 1.5 0.7 0.2

10.4 0.5

11.6 1.5 2.7 7.1

12.5 4.2 0.0 3.1 0.7 7.1 3.8

9.1 15.8 12.4 10.9 2.0 4.9 0.7 6.7 2.7 0.5 6.2 4.4

15.3 10.4 0.2 9.3 9.3 0 .o 2.9

17.5 1.1

18.4 14.7 3.6 9.1 9.8 4.9 0.5 4.9 0.2

18.4 2.4

10.7 11.8 12.2 27.8 0.7 6.5 5.8 6.2 2.7 0.2 5.3

40.9 18.7 8.7 4.0

11.8 14.5 0.5 4.0

27.6 1.5

20.4 26.5 4.9

13.8 17.6 14.0 2 .o 9.3 1.1

18.5 2.0

.969

.352 389 ,954 .253 .983 267 256 .902

-.593 .538 374 .986 .8 18 .782

-.576 .999

-.352 .987 .984 ,999 .974 .999 .983 .953 .582 ,859 .936 .950 .372 .906

-.973

.939

.I24

.79 1

.91 I

.064

.966

.752 ,732 314 .352 .290 .763 .973 .668 .611 .33 1 .999 .124 .975 .968 .999 .950 .998 .967 .090 .338 .737 376 .903 .I38 .82 1 .947

15.388 .I41

3.783 10.181

.068 28.677

3.031 2.730 4.390

.543

.408 3.223

35.368 2.016 1 S72 .496

754.662 ,141

38.444 30.57 1

755.992 18.824

466.958 29.152 9.938

,511 2.807 7.075 9.348

.I60 4.573

17.946

.0835

.38 13

.154

.101

.414

.06 15

.1684

.1755

.1451

.7035

.317

.1644

.055

.196

.215

.697

.0115

.6 187

.053

.059

.0115

.076 ,014 .06 I .102 ,301 .174 ,118 .105 .375 .143 .923

continued

144 BRIAN MULLEN

(Table 1. continued)

Regression statistics # Self" 1 1 1 #Otherb 0 1 7.5 OTRC .OO S O .88 R R* F(1,l) P

33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

Mean

1.8 0.5 1.1 2.7 8.5 16.9 0.2, 0.5 1.6 0.4 2.2 2.5 0.5 1.6 2.0 1.6 3.5 2.4 0.9 0.4 0.7 0.0 2.7 1.6 0.4 1.1 0.7

17.3 26.9 29.1 5.3 5.6 1.5 0.0 10.2 15.6

31.1 51.3 63.1 4.7 4.0 4.4

13.6 20.0 23.8 9.5 24.4 32.7 8.2 4.4 4.2 6.7 13.3 17.5 6.7 6.7 8.0 2.9 10.4 14.2 4.6 9.2 11.5

-.602 .983 .922 .952 ,983 .489

-.468 .65 1 .497 .964

-.785 .995 .997

P.497 .998 .996

-.92 1 .999 .824 .994 .889

,363 .967 350 ,905 .966 .239 .219 .424 .247 .929 .616 .99 I .995 .247 .995 ,993 348 ,998 .679 .988 .790

.570 28.909

5.681 9.575

28.676 ,315 .28 1 .735 .328

13.178 1.607

105.071 193.165

.328 218.367 140.285

5.574 415.877

2.177 84.641

.707

.06 1 ,130 .104 .06 1 ,335 .658 .273 .332 .089 .7815 .03 I .022 .668 .02 1 .026 3 6 % .015 .193 ,035

Note. The numbers 1-52 identify subjects (Hahn, 1940, Table I). a(#Self #Stutterers). '(#Others #Audience). '(OTR = #Others/(#Others + # Self)).

.9999999), indicate that these 52 regression analyses did not produce signifi- cantly heterogeneous results. Therefore, the combination meta-analytic sta- tistics reported above do appear to be based upon a relatively homogeneous group of hypothesis tests.

Discussion

These results are supportive of the self-attention theory approach. Stutter- ing was observed to be significantly and powerfully related to the Other-Total

x 2 = 0. regardless of the heterogeneity of the effect sizes. In an attempt to estimate the actual meta-analytic x 2 , 2.9 was subtracted from N , rather than 3. This approaches the conventional formula, while still producing a calculable xz.

STUTTERING AND THE OTR 145

Ratios characterizing the audience conditions. However, the precision and the power of this secondary analysis is limited by Hahn’s (1940) small number of audience conditions (three), and by the failure to specify the precise number of people in the larger audience condition. Fortunately, Porter’s (1 939) proce- dure reduces these difficulties, by employing a larger number of audience conditions (five), and by precisely specifying the sizes of the audiences in each condition.

Study 2 (Porter, 1939)

The procedure of data collection is described in detail in Porter (1939). Briefly, 13 stutterers receiving remedial speech instruction read aloud 500- word passages under each of five audience conditions. These audience condi- tions (with their corresponding Other-Total Ratios) were: (1) alone (OTR .OO); (2) audience on one (OTR = .50); (3) audience of two (OTR .67); (4) audience of four (OTR 30); and, (5) audience of eight (OTR 39). The computation of these Other-Total Ratios is illustrated in Table 2.

The analyses of these data were conducted similarly to the analyses reported for Study I . For each of the 13 stutterers, the percent of words stuttered in each audience condition was regressed upon the corresponding five Other- Total Ratios, resulting in 13 regression analyses.

Results

The results of the regression analyses for each of the 13 stutterers are present inTable 2. Again, meta-analytic statistics will be used to summarize the results of these regression analyses.

Combination. The standard normal deviate for combination of significance levels isZ 5.504296 (p = .0000000207), indicating that the combined results of these regression analyses were unlikely to have occurred if the null hypothesis were true. This meta-analytic combination of significance levels is associated with a fail-safe number for the .05 level of significance of N(fs .05) 132.550962, suggesting that similar regression analyses of approximately 133 stutterers showing no effect of audience size on stuttering would be required to move the overall combined probability back to the “just significant” conven- tion o f p = .05. The mean Fisher Z for combination of effect size was Z = 1.1205 17. This corresponds to a mean correlation coefficient of R = .807749, a coefficient of determination of R 2 = .652458, and a mean Cohen’s stan- dardized difference between the means o f d = 2.740329. Thus, these regression analyses tend to produce results which are statistically significant and of strong magnitude.

Comparison. The results of the diffuse comparison of significance levels (x:, 9.977466,p= .617938) and the diffuse comparison of effect sizes (x:, =

146 BRIAN MULLEN

Table 2

Percent of Words Stuttered with Different Size Audiences, and Regression Analyses (Porter, 1939)

Regression statistics # Selfa 1 1 1 1 1 #Otherb 0 1 2 4 8 OTRC .OO S O .67 .80 .89 R R 2 F(1,3) p

A 3.6 12.8 20.6 28.4 39.8 B 0.0 0.6 0.8 2.2 3.0 C 5.6 15.2 18.2 25.0 29.6 D 0.4 46.0 51.2 66.6 73.6 E 4.0 13.0 51.6 20.6 25.2 F 0.6 1.0 11.0 11.0 1.2 G 0.0 0.2 3.0 3.0 1.4 H 1.4 3.0 5.2 5.8 3.8 I 5.0 14.6 27.0 21.2 18.4 J 0.2 0.8 0.8 1.2 0.8 K 2.0 4.8 6.4 6.4 4.0 L 2.2 3.6 2.0 0.8 6.6 M 11.8 15.6 10.0 14.4 10.2

Mean 2.8 9.5 13.0 16.0 16.7

,926 3 5 7 18.00 .011 .855 .732 8.18 .0315 .967 .936 43.70 .003 .994 .988 153.17 .0005 .576 .331 1.49 .155 .457 .209 .79 .2795 .689 .475 2.71 .099 .817 .667 6.01 .0455 317 .667 6.01 .0455 363 .745 8.76 .029 .720 .518 3.23 .085 .305 .093 .31 .309 ,103 .011 .03 .569 308 .652

Note. The letters A-M identify subjects (Porter, 1939, Table IV). a(#Self= #Stutterers). b(#Others= #Audience). ‘(OTR=Others/ #Others= # Self)).

14.448543, p .272986) suggest that these 13 regression analyses did not produce significantly heterogeneous results. Therefore, the combination meta-analytic statistics reported above appear to be based upon a homogene- ous group of hypothesis tests.

Note that these patterns of results are not simply due to, or a misrepresenta- tion of, the mere size of the audience. Analogous sets of 52 and 13 regression analyses were conducted on Hahn’s and Porter’s data sets, using the mere size of the audience as the predictor of the percent of words stuttered. For the “mere number” analysis of Hahn’s data, the meta-analytic combination of effect sizes produced a mean correlation coefficient of R = ,784132, and a mean coefficient of determination of R* .614862 (compared to the R 389027 and the R 2 = .790369 obtained using the Other-Total Ratio). Sim- ilarly, for the “mere number” analysis of Porter’s data, the meta-analytic combination of effect sizes produced a mean correlation coefficient of R = .622536, and a mean coefficient of determination of R2 = .387551 (compared

STUTTERING AND THE OTR 147

to the R = 307749 and the R 2 .652458 obtained using the Other-Total Ratio)

Consider further the regression coefficients for the prediction of verbal disfluencies by the Other-Total Ratio after partialing out the variability due to mere audience size. Such partial regression coefficients could be derived for each of Porter’s 13 subjects.7 The resulting meta-analytic statistics for combi- nation of significance levels (2 4.652534, p .00000167618, N(fs .05) 90.989766) and for combination of effect sizes(Z I .247787,R = .847662,R* .718537,d= 3.195487) reveal that theother-Total Ratio provides statistically significant and powerful predictions even after the linear effects of the mere number of audience members have been partialed out.

General Discussion

The results of these two secondary analyses reveal that the Other-Total Ratio is able to significantly and meaningfully account for the effects of audience size on stuttering. Considering that Hahn’s and Porter’s data sets were collected over 40 years ago, in divergent locations, with different proce- dures, and (obviously) without concern for the present conceptual frame- work, these results are especially encouraging.

There are two major implications of these results for a social psychological perspective on stuttering, consistent with Wicklund’s (1975) treatment of this subject. First, situations which enhance the stutterer’s self-attention are likely to exacerbate verbal disfluency. This is examplified in Hahn’s and Porter’s manipulations of increasing audience size, as well as in Bloodstein’s (1969) treatment of the effects of highly evaluative audiences on stuttering.

Second, situations which reduce the stutterer’s self-attention are likely to mitigate verbal disfluency. One example of this can be found in Swift and Hedrick’s (1917) discussion of the use of “starters.” Starters are physical movements or gestures which accompany disfluencies, and which seem to facilitate speech by directing the stutterer’s attention away from the self (cf. Wicklund, 1975). Alternatively, Barber (1939) reported that reading in chorus with someone else could reduce stuttering. This “chorus reading” would reduce the stutterer’s Other-Total Ratio. That is, the stutterer reading along with other people would be less likely to emerge as the perceptual figure of the group, and self-attention generated disfluencies should be reduced.

More generally, these secondary analyses illustrate a novel application of the self-attention theory Other-Total Ratio perspective to the prediction of an

’Similar analyses could not be conducted for Hahn’s 52 subjects. Since the degrees of freedom for a partial regression coefficient is defined asdf= ( N - 2 -the number of predictors being partial out), this would have produced partial regression coefficients based on df = 0 for Hahn’s data (where N = 3).

148 BRIAN MULLEN

overt behavior in a realistic social setting. The Other-Total Ratio provides a simple, a priori, descriptive and explanatory means of predicting social be- haviors that vary as a negatively accelerating function of group size. The present results lend further support to the application of this self-attention theory approach to the effect of the group on the individual.

References

Barber, V. (1939). Studies in the psychology of stuttering, XIV. Chorus reading as a distraction in stuttering. Journal of Speech Disorders, 4,

Baumeister, R. F. (1984). Choking under pressure: Self-consciousness and paradoxical effects of incentives on skillful performance. Journal of Per- sonality and Social Psychology, 46, 6 10-620.

Bechtel, R. (1984). From undermanning to positions of responsibility: Toward a theory of situational determinants of healthy behavior. Unpub- lished manuscript, University of Arizona.

Bloodstein, D. (1969). A Handbook on Stuttering. Chicago, IL: National Easter Seal Society.

Brown, S. F. (1945). The loci of stuttering in the speech sequence. Journal of Speech Disorders, 10, 181-192.

Carver, C. S. & Scheier, M . F. (1981). Attention and Self-Regulation: A Control Theory Approach to Human Behavior. New York: Springer- Verlag.

Coren, S., Porac, C., & Ward, L. M. (1979). Sensation and Perception. New York: Academic Press,

Diener, E. (1980). Deindividuation: The absence of self-awareness and self- regulation in group members. In P. B. Paulus (Ed.), Psychology of Group Influence. Hillsdale, NJ: Erlbaum.

Dittman, A. T., & Lewellyn, L. G. (1969). Body movement and speech rhythm in social conversation. Journal of Personality and Social Psychology, 11,

Hahn, E. F. (1940). A study of the relationship between the social complexity of the oral reading situation and the severity of stuttering. Journal of Speech Disorders, 5,5-14.

Hoffer, E. (1955). The passionate state of mind. New York: Harper & Row. Kimble, G., & Perlmutter, L. (1970). The problem of volition. Psychological

Koffka, K . (1935). Principles of Gestaltpsychology. New York: Harcourt &

Langer, E., & Imber, L. G . (1979). When practice makes imperfect: Debilitat-

371-383.

98-106.

Review, 77, 361 -384.

Brace.

STUTTERING AND THE OTR 149

ing effects of overlearning. Journal of Personality and social Psychology,

Mullen, B. ( 1 983a). Operationalizing the effect of the group on the individual: A self-attention perspective. Journal of Experimental Social Psychology, 19 295-322.

Mullen, B. (1983b). Social facilitation, social impairment and social loafing: A sev-attentionperspective. Paper presented at the 1983 annual meeting of the Kentucky Academy of Sciences, Louisville, KY.

Mullen, B. (1985). Participation in class discussion as a function of group composition: A self-attention perspective. Paper presented at the 1985 annual meeting of the American Educational Research Association, Chi- cago, IL.

Mullen, B., (1984). Participation in religious groups as a function of group composition: A self-attention perspective. Journal of Applied Social Psy-

Mullen, B., & Peaugh, S. (1986). Focus of attention in the Executive Office Building: A self-attention perspective. Unpublished manuscript, Syracuse University.

Mullen, B., & Rosenthal, R. (1985). BASIC meta-analysis: Procedures and programs. Hillsdale, NJ: Lawrence Erlbaum Associates.

Porter, H. V. K . (1939). Studies in the psychology of stuttering, XIV. Stutter- ing phenomenon in relation to size and personnel of audience. Journal of Speech Disorders, 4,323-333.

Rosenthal, R. (Ed.). (1980). Quantitative assessment of research domains. San Francisco, CA: Josey-Bass.

Rosenthal, R. (1983). Assessing the statistical and social importance of the effects of psychotherapy. Journal of Consulting and Clinical Psychology,

37,2014-2024.

chology, 14, 509-5 18.

51,4-13. Schwartz, M. F. (1976). Stuttering solved. New York: McGraw-Hill. Swift, W. B., & Hedrick, S. (1917). Sidetracking of stuttering by “starters.”

Journal of Applied Psychology, 1, 84-88. Wicklund, R. A. (1975). Objective self-awareness. In L. Berkowitz (Ed.),

Advances in experimentalsocialpsychology (Vol. 8). New York: Academic Press.