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Effect of referent similarity and communication mode on verbal encoding
JOURNALOF V]EBBALLEARNINGAND VERBALBEHAVIOR6, 359--863 (1967)
Effect of Referent Similarity and Communication Mode on Verbal Encoding ROBERT M. KBaVSS aND StoNEY WE1NHEIMER Bell Telephone Laboratories, Incorporated, Murray Hill, New Jersey 07971
The Ss in this experiment, working either singly (Monologue condition) or in pairs (Dialogue condition), attempted to solve a problem which required that they communicate information about four color chips. Sets of either Similar or Dissimilar colors were employed. The codability of colors (as measured both by name length and interpersonal agreement) was greater for colors in Dissimilar sets than for those in Similar sets. As measured by interpersonal agreement, but not name length, codabflity was greater in the Dialogue condition than in the Monologue condition. In addition, for both measures, the two independent variables interacted significantly. The results were discussed in terms of a model of interpersonal communication. Previous studies have established that one index of a referents codability is the number of words used, on the average, to encode it (Brown, 1965; Glanzer and Clark, 1964; Lantz and stefltre, 1964; Brown and Lenneberg, 1954). Highly codable referents tend to be given relatively short names, and less codable referents generally receive longer names. The present experiment investigates two factors which affect the verbal encoding of a referent. What, aside from intrinsic properties of a referent (e.g., the "goodness" of the gestalt it forms), determines its codability? One determinant is the similarity among the referents from which it is to be distinguished. As Brown (1965, p. 265) points out, when the elements of a set of referents are very much alike it is necessary to use a name which is long, and hence low in codability, to distinguish any one element from the others. Other factors will also affect a referent's codability. The authors, in a previous study
(Krauss and Weinheimer, 1964a), found that the way a referent was encoded (as measured by the length of its name) changed as a function of repeated reference. Visually separated Ss worked to solve a problem which required that they communicate about novel graphic forms, i.e., forms for which they had no standardized names. The number of words used to refer to a form decreased over the course of successive references to it. Frequently referred to forms ended up with relatively short names, while less frequently mentioned forms were given longer names. Such a process is analogous to one often observed in natural languages (Zipf, 1935). In a subsequent experiment it was found that the shortening of a name given a referent depends strongly on the speaker's interaction with another person. When Ss tape-recorded messages to be decoded later by some other person, they tended to assign longer names to the referents and to shorten them at a slower rate (Krauss and Weinheimer, 1964b). These findings 359
360
KRAUSS AND WEINHEIMER
p r o v i d e e v i d e n c e for the hypothesis t h a t the w a y i n w h i c h a r e f e r e n t u l t i m a t e l y comes to b e e n c o d e d also d e p e n d s u p o n the a m o u n t of f e e d b a c k w h i c h t h e transm i t t e r of a message receives from its recipient. T h e m o r e f e e d b a c k a speaker c a n receive from his listener, the shorter will b e the n a m e s a s s i g n e d to referents. T h e e x p e r i m e n t to b e r e p o r t e d here was d e s i g n e d to test the f o l l o w i n g hypotheses, ( a ) T h e c o d a b i l i t y of a r e f e r e n t will v a r y as a f u n c t i o n of the similarity of the elem e n t s of the r e f e r e n t set: t h e m o r e similar are the m e m b e r s of the set, the lower will b e the c o d a b i l i t y of each. ( b ) T h e c o d a b i l i t y of a r e f e r e n t will vary as a f u n c tion of t h e i n t e r a c t i o n of t h e speaker a n d listener: c o d a b i l i t y will b e g r e a t e r w h e n speaker a n d listener i n t e r a c t directly t h a n w h e n t h e y do n o t so interact. METHOD
Stimulus Materials. Twenty-four Munsell color chips having the same notations as those used by Brown and Lenneberg (1954) were used as the referents. Each was mounted on a white 8 X 5 in card. The four chips, which on a given trial comprised the referent set, were displayed in a cardboard frame so that the four cards were contiguous. Illumination was provided by a General Electric Standard Daylight fluorescent /amp. Procedure. The effect of two factors was examined: communication mode and referent set. The Ss participated either singly, in a Monologue condition, or in pairs, in a Dialogue condition. For all Ss, each stimulus color appeared twice, once in a referent set of Similar colors and once in a Dissimilar set. In the Monologue condition, the S was shown four color chips, numbered one through four. She was told that her task was to make a tape recording which would later be played back to another person who would have the same four color chips arranged in a different order. This person's task was to rearrange the four chips in the original order. In essence, then, the S's task was to encode a message about the referent colors with the expectation that at some fnture time another person would have to decode the message. In the Dialogue condition, each member of
the pair of visually separated Ss was given the same four referent colors arranged in a different order. One S's cards were numbered one through four and the other's were lettered A through D. Their task was to discover the letter-number pairs which identified the matching color chips. No restriction was placed on the contents of their interaction. The Similarity or Dissimilarity of the referent set was defined by the distances in the Munsell solid among the four stimulus colors. The Brown and Lenneberg 24-color series was originally developed to provide a reasonably even coverage of the shell of the color solid. The 24 colors were systematically arranged on the dimension of hue in a series of graduated changes. In the Similar condition, the four referent colors were adjacent in the hue-ordered series. In the Dissimilar condition, the four colors were six (of a series of 24) steps apart. 1 Each S or pair of Ss saw all 24 colors twice, once in a Similar set and once in a Dissimilar set. Hence, a total of 12 four-color referent sets (six Similar and six Dissimilar) were presented to each S or pair of Ss. The order in which the sets were presented, as well as the arrangement of the individual colors within the sets, was randomly determined. All Ss were instructed to work at their own speed, and no time limit was imposed upon them. No feedback as to the adequacy of the names chosen (in the Monologue condition) or the correctness of the color matches (in the Dialogue condition) was given by the E. Subjects. Thirty female clerical and secretarial employees of the Bell Telephone Laboratories served as Ss, I0 individual Ss in the Monologue condition and 10 pairs in the Dialogue condition. All were high school graduates between the ages of 18 and 85, and all had volunteered to participate during their regular working hours. To conserve time and in view of the low incidence of l i t is not assumed that the four colors in either Similar or Dissimilar arrays are perceptually equidistant. As Farnsworth (1961) has pointed out, there is at present no completely satisfactory means of specifying the perceptual distance between pairs of colors which differ on more than one dimension. All that is maintained here is that the average similarity of the colors is greater in the Similar sets than in the Dissimilar sets. That this is the case is obvious both from an examination of the Munsell notations of the stimuli used (given in Brown and Lenneberg, 1954, p. 459) and, more important, from an inspection of the sets of color chips themselves.
VERBAL ENCODING
defective color vision among females [Judd (1952) estimates it as about 0.4%], Ss were not screened for color blindness. Dependent Variables. Two measures of the dependent variable, codability, were calculated: name length and interpersonal agreement. For name length, the first name given to each color (on each of the two presentations in which it appeared) was transcribed and the number of words it contained was calculated. Initial articles were not counted as part of a name. It will be recalled that six Similar and six Dissimilar sets, each consisting of four color chips, were presented. The mean length of the four names given on each of the 12 presentations was calculated. Hence, each S or pair of Ss contributed 12 scores, 6 based on the mean lengths of the names given colors in Similar sets and 6 based on the names given colors in Dissimilar sets. Interpersonal agreement scores were calculated for each of colors by the method employed b y Brown and Lenneberg. For each color, in each of the four conditions, the number of different responses was subtracted from the frequency of the most popular response, and a constant added so that all scores would be positive in sign. (For further details see Brown and Lenneberg, 1954, p. 459. ) RESULTS
An analysis of variance of the namelength scores was performed. Consistent with our hypothesis, a statistically significant main effect was found for the similarity of the referent set, F( 1, 200) = 41.71, p < .001. Color names are longer for colors in Similar sets than for those in Dissimilar sets. However, contrary to our prediction, the effect of communication mode, although in the hypothesized direction, is nonsignificant, F(1, 1 8 ) = 1.44. A significant Set X Mode interaction was also obtained, F(1, 2 0 0 ) = 6 . 4 6 , p < . 0 5 . The mean name lengths in the four experimental conditions, shown in Table 1, indicate the nature of this interaction: greater differentiation between the lengths of color names in Similar and Dissimilar sets occurs in the Dialogue mode than in the Monologue mode.
361
TABLE 1 MEANS OF THE TWO MEASURES OF CODABILITY UNDER THE FOUR EXPERIMENTAL TREATMENTS
Treatment
Name length
Interpersonal agreement
Similar.Dialogue Similar-Monologue Dissimilar-Dialogue Dissimilar-Monologue
3.33 3.66 1.68 ~. 94
5.54 4. ~5 11.37 6.08
As was noted above, four interpersonal agreement scores were computed for each color, one for each of the conditions under which it appeared. An analysis of variance was performed on these scores. For the interpersonal agreement index, significant main effects were obtained for both independent variables: interpersonal agreement is greater in Dissimilar sets relative to the Similar sets, F(1, 28) = 58.99, p < .001 and in the Dialogue mode relative to the Monologue mode, F(1, 2 8 ) = 48.50, p < .001. The pattern of the statistically significant Set)< Mode interaction, F(1, 23) - - 15.89, p < .001, matches that found for the name-length variable, as is indicated by the means in Table 1. Additionally, and not surprising, a significant main effect is found for Colors, F(23, 23) = 5 . 9 8 , p < .001: colors differ among themselves as to the amount of interpersonal agreement they engender. Neither of the other two first-order interactions (Set X Color and Mode X Color) approaches significance. It is instructive to examine t h e relationship between certain of Brown and Lenneberg's (1954) findings and our own. These investigators have published interpersonal agreement ratings for the 24 referent colors. In their experiment, the color chips were exposed individually. Hence, these names may be thought of as reflecting the intrinsic codability of the colors, uncontaminated by the referent set. Productmoment correlations were computed be-
362
KaAUSS A N D WEINHEIMER TABLE
CORRELATIONS OF BROWN AND LENNEBERG'S INTERPERSONAL AGREEMENT INDEX FOR THE ~4 COLORS USED AND TWO MEASURES I N THIS EXPERIMENT
Treatment
Mean name length
Interpersonal agreement index
Similar-Dialogue Similar-Monologue Dissimilar-Dialogue Dissimilar-Monologue
--. 24 - . 50** --. 43" --. 40*
.80 .62** .55** .55**
*p < .05 ** p < .01
tween these ratings and the mean name lengths found in the present experiment, for each of the four experimental conditions. 2 These values are shown in Table 2. The values of r range from --.40 to --.50 (all significantly different from zero) except in the Similar-Dialogue condition, where it falls to --.24 (n.s.). ( Brown and Lenneberg found a correlation of --.49 between name length and interpersonal agreement.8 Similarly, the correlations were computed between Brown and Lenneberg's interpersonal agreement index and our own for each of our four experimental conditions. These values, displayed in Table 2, range from .55 to .62 (all significant beyond the .01 level) except for the Similar-Dialogue condition, where r-----.80 (n.s.). DISCUSSION
Whether one uses name length or interpersonal agreement as a measure of cod"~It would have been preferable to compare our mean lengths with those found by Brown and Lenneberg. Unfortunately, these investigators did not publish mean length data for individual colors. ~The actual value reported is +.49; Brown and Lenneberg report their results in terms of the brevity of the color name. In our own work we have found it more useful to think of a name as having a mean length, and hence have reversed the sign of this measure.
ability, it is clear that referents have greater codability when they appear in Dissimilar sets than when they appear in Similar sets. It is also the case that codability as measured by interpersonal agreement is greater in the Dialogue mode than in the Monologue mode. Finally, these two variables interact significantly on both measures. The findings for the effects of similarity of the referent set are explicable in terms of a model of interpersonal communication proposed by Rosenberg and Cohen (1964). Briefly, their model considers the process determining a speaker's choice of verbal response in a situation in which he must provide a message which will enable a listener to discriminate one referent from another. It postulates that the speaker samples randomly from his repertoire of names for the referent; names are sampled at a rate proportional to the frequency with which each is applied to the referent in isolation. Having been sampled, the probability that a name will actually be emitted is determined by a comparison between the name's applicability to the referent and its applicability to the other members of the referent set. When the speaker estimates that the name has greater applicability to the referent than to nonreferents, there is a high likelihood that he will emit it. When the sampled name is estimated to be more applicable to the nonreferents, the speaker is likely to reject t h e name and sample a new one. This process continues until a name which meets the comparison criterion is sampled and emitted. Colors similar in hue tend to evoke the same name (Lenneberg, 1961). Hence the Rosenberg-Cohen model would predict that the color names which have the highest probability of being sampled for colors in a Similar set are unlikely to pass the comparison test. The name which ulti-
363
VERBAL ENCODING
mately is emitted will not be the "popular" for that color (since these too often will also be applicable to the other colors in the set), but rather the unusual, low-infrequency names, sampled from the tail of the rank-frequency distribution. For this reason, the names given to such colors will be low on an interpersonal agreement index which is essentially a measure of communality. And, because it so often is necessary to use compound names with qualifiers and color combinations, such names will tend to be relatively long. For colors in Dissimilar sets, however, the "popular" responses have a high probability of being emitted, since the likelihood of their being applicable to the other colors in the set is relatively small. Hence interpersonal agreement will be high and the names given will tend to be relatively short. The effects of the communication-mode variable are somewhat less straightforward. Although large and significant main effects were found for the interpersonal agreement measure, no statistically significant main effect was found for name length. This latter finding is at variance with resuits obtained by Krauss and Weinheimer (1964b), who found large differences in the lengths of names given to novel geometric forms in Monologue and Dialogue conditions. It may be the case that our inability to replicate these earlier results is attributable to differences in the stimulus materials employed. It further strengthens the conclusion, drawn from the work of Brown and Lenneberg (1954) and Lantz and Stefltre (1964), that interpersonal agreement is a more sensitive measure of codability than name length. It is then clear that the way in which a referent is encoded in communication is affected by factors extrinsic to the referent itself. In addition to the factors discussed above, encodi0g should also be
affected by such variables as the information a speaker has about his listener (Ratner and Rice, 1968), the speaker's emotional state (Stoltz and Tannenbaum, 1968), and the relative stress placed on accuracy vs. speed of communication. REFERENCES
BROWN, R. Social psychology. New York: The Free Press, 1965. BROWN, R., AND LENNmSmaC, E. H. A study in language and cognition. 1. abnorm, soc. Psychol., 1954, 49, 454--462. FAI~SWORTn, D. A temporal factor in color discrimination. In Visual problems of color: Symposium. Vol. 2. New York: Chemical Publishing Co., 1961. GLANZER,M., ANDCLAm:,W. H. The verbal loop hypothesis: Conventional figures. Amer. 1. Psychol., 1964, 77, 622-626. JtroD, D. B. Color in business, science and industry. New York: Wiley, 1952. Kaxuss, R. M., AND WEINHEnVmn,S. Changes in reference phrases as a function of frequency of usage in social interaction. Psychon. Sci., 1964, 1, 118-114 (a). KaAuss, R. M., AND WEINrmlMER, S. The effect of feedback on changes in reference phrases. Paper read at meeting of the Psychonomic Society, Niagara Falls, Ontario, Canada, 1964 (b). LANTZ, DELEE, AND STEFrLm~,V. Language and cognition revisited. ]. abn. soc. Psychol., 1984, 69, 472-481. LEHNV-BEnC,E. H. Color naming, color recognition, color discrimination: a re-appraisal. Percept. mot. Skills, 1981, 12, 875-882. RATHER, S. C., AND RICE, F. E. The effect of the listener on the speaking interaction. Psychol. Rec., 1968, 13, 265-268. ROSENBERC, S., AND COHEN, B. D. Referential processes of speakers and listeners. Psychol. Rev., 1966, 73, 208-281. ROSENaERC, S., AND COHEN, B. D. Speakers' and listeners' processes in a word-communication task. Science, 1984, 145, 1201-1208. STOLTZ, W. S., AND TANNENBAUM, P. H. Effects of feedback on oral encoding behaviour. Lang. Speech, 1963, 6, 218-228. ZIPF, G. K. The psycho-biology of language. Boston: Houghton Mif~in, 1935. (Received August 5, 1965)
Effect of Referent Similarity and Communication Mode on Verbal Encoding ROBERT M. KBaVSS aND StoNEY WE1NHEIMER Bell Telephone Laboratories, Incorporated, Murray Hill, New Jersey 07971
The Ss in this experiment, working either singly (Monologue condition) or in pairs (Dialogue condition), attempted to solve a problem which required that they communicate information about four color chips. Sets of either Similar or Dissimilar colors were employed. The codability of colors (as measured both by name length and interpersonal agreement) was greater for colors in Dissimilar sets than for those in Similar sets. As measured by interpersonal agreement, but not name length, codabflity was greater in the Dialogue condition than in the Monologue condition. In addition, for both measures, the two independent variables interacted significantly. The results were discussed in terms of a model of interpersonal communication. Previous studies have established that one index of a referents codability is the number of words used, on the average, to encode it (Brown, 1965; Glanzer and Clark, 1964; Lantz and stefltre, 1964; Brown and Lenneberg, 1954). Highly codable referents tend to be given relatively short names, and less codable referents generally receive longer names. The present experiment investigates two factors which affect the verbal encoding of a referent. What, aside from intrinsic properties of a referent (e.g., the "goodness" of the gestalt it forms), determines its codability? One determinant is the similarity among the referents from which it is to be distinguished. As Brown (1965, p. 265) points out, when the elements of a set of referents are very much alike it is necessary to use a name which is long, and hence low in codability, to distinguish any one element from the others. Other factors will also affect a referent's codability. The authors, in a previous study
(Krauss and Weinheimer, 1964a), found that the way a referent was encoded (as measured by the length of its name) changed as a function of repeated reference. Visually separated Ss worked to solve a problem which required that they communicate about novel graphic forms, i.e., forms for which they had no standardized names. The number of words used to refer to a form decreased over the course of successive references to it. Frequently referred to forms ended up with relatively short names, while less frequently mentioned forms were given longer names. Such a process is analogous to one often observed in natural languages (Zipf, 1935). In a subsequent experiment it was found that the shortening of a name given a referent depends strongly on the speaker's interaction with another person. When Ss tape-recorded messages to be decoded later by some other person, they tended to assign longer names to the referents and to shorten them at a slower rate (Krauss and Weinheimer, 1964b). These findings 359
360
KRAUSS AND WEINHEIMER
p r o v i d e e v i d e n c e for the hypothesis t h a t the w a y i n w h i c h a r e f e r e n t u l t i m a t e l y comes to b e e n c o d e d also d e p e n d s u p o n the a m o u n t of f e e d b a c k w h i c h t h e transm i t t e r of a message receives from its recipient. T h e m o r e f e e d b a c k a speaker c a n receive from his listener, the shorter will b e the n a m e s a s s i g n e d to referents. T h e e x p e r i m e n t to b e r e p o r t e d here was d e s i g n e d to test the f o l l o w i n g hypotheses, ( a ) T h e c o d a b i l i t y of a r e f e r e n t will v a r y as a f u n c t i o n of the similarity of the elem e n t s of the r e f e r e n t set: t h e m o r e similar are the m e m b e r s of the set, the lower will b e the c o d a b i l i t y of each. ( b ) T h e c o d a b i l i t y of a r e f e r e n t will vary as a f u n c tion of t h e i n t e r a c t i o n of t h e speaker a n d listener: c o d a b i l i t y will b e g r e a t e r w h e n speaker a n d listener i n t e r a c t directly t h a n w h e n t h e y do n o t so interact. METHOD
Stimulus Materials. Twenty-four Munsell color chips having the same notations as those used by Brown and Lenneberg (1954) were used as the referents. Each was mounted on a white 8 X 5 in card. The four chips, which on a given trial comprised the referent set, were displayed in a cardboard frame so that the four cards were contiguous. Illumination was provided by a General Electric Standard Daylight fluorescent /amp. Procedure. The effect of two factors was examined: communication mode and referent set. The Ss participated either singly, in a Monologue condition, or in pairs, in a Dialogue condition. For all Ss, each stimulus color appeared twice, once in a referent set of Similar colors and once in a Dissimilar set. In the Monologue condition, the S was shown four color chips, numbered one through four. She was told that her task was to make a tape recording which would later be played back to another person who would have the same four color chips arranged in a different order. This person's task was to rearrange the four chips in the original order. In essence, then, the S's task was to encode a message about the referent colors with the expectation that at some fnture time another person would have to decode the message. In the Dialogue condition, each member of
the pair of visually separated Ss was given the same four referent colors arranged in a different order. One S's cards were numbered one through four and the other's were lettered A through D. Their task was to discover the letter-number pairs which identified the matching color chips. No restriction was placed on the contents of their interaction. The Similarity or Dissimilarity of the referent set was defined by the distances in the Munsell solid among the four stimulus colors. The Brown and Lenneberg 24-color series was originally developed to provide a reasonably even coverage of the shell of the color solid. The 24 colors were systematically arranged on the dimension of hue in a series of graduated changes. In the Similar condition, the four referent colors were adjacent in the hue-ordered series. In the Dissimilar condition, the four colors were six (of a series of 24) steps apart. 1 Each S or pair of Ss saw all 24 colors twice, once in a Similar set and once in a Dissimilar set. Hence, a total of 12 four-color referent sets (six Similar and six Dissimilar) were presented to each S or pair of Ss. The order in which the sets were presented, as well as the arrangement of the individual colors within the sets, was randomly determined. All Ss were instructed to work at their own speed, and no time limit was imposed upon them. No feedback as to the adequacy of the names chosen (in the Monologue condition) or the correctness of the color matches (in the Dialogue condition) was given by the E. Subjects. Thirty female clerical and secretarial employees of the Bell Telephone Laboratories served as Ss, I0 individual Ss in the Monologue condition and 10 pairs in the Dialogue condition. All were high school graduates between the ages of 18 and 85, and all had volunteered to participate during their regular working hours. To conserve time and in view of the low incidence of l i t is not assumed that the four colors in either Similar or Dissimilar arrays are perceptually equidistant. As Farnsworth (1961) has pointed out, there is at present no completely satisfactory means of specifying the perceptual distance between pairs of colors which differ on more than one dimension. All that is maintained here is that the average similarity of the colors is greater in the Similar sets than in the Dissimilar sets. That this is the case is obvious both from an examination of the Munsell notations of the stimuli used (given in Brown and Lenneberg, 1954, p. 459) and, more important, from an inspection of the sets of color chips themselves.
VERBAL ENCODING
defective color vision among females [Judd (1952) estimates it as about 0.4%], Ss were not screened for color blindness. Dependent Variables. Two measures of the dependent variable, codability, were calculated: name length and interpersonal agreement. For name length, the first name given to each color (on each of the two presentations in which it appeared) was transcribed and the number of words it contained was calculated. Initial articles were not counted as part of a name. It will be recalled that six Similar and six Dissimilar sets, each consisting of four color chips, were presented. The mean length of the four names given on each of the 12 presentations was calculated. Hence, each S or pair of Ss contributed 12 scores, 6 based on the mean lengths of the names given colors in Similar sets and 6 based on the names given colors in Dissimilar sets. Interpersonal agreement scores were calculated for each of colors by the method employed b y Brown and Lenneberg. For each color, in each of the four conditions, the number of different responses was subtracted from the frequency of the most popular response, and a constant added so that all scores would be positive in sign. (For further details see Brown and Lenneberg, 1954, p. 459. ) RESULTS
An analysis of variance of the namelength scores was performed. Consistent with our hypothesis, a statistically significant main effect was found for the similarity of the referent set, F( 1, 200) = 41.71, p < .001. Color names are longer for colors in Similar sets than for those in Dissimilar sets. However, contrary to our prediction, the effect of communication mode, although in the hypothesized direction, is nonsignificant, F(1, 1 8 ) = 1.44. A significant Set X Mode interaction was also obtained, F(1, 2 0 0 ) = 6 . 4 6 , p < . 0 5 . The mean name lengths in the four experimental conditions, shown in Table 1, indicate the nature of this interaction: greater differentiation between the lengths of color names in Similar and Dissimilar sets occurs in the Dialogue mode than in the Monologue mode.
361
TABLE 1 MEANS OF THE TWO MEASURES OF CODABILITY UNDER THE FOUR EXPERIMENTAL TREATMENTS
Treatment
Name length
Interpersonal agreement
Similar.Dialogue Similar-Monologue Dissimilar-Dialogue Dissimilar-Monologue
3.33 3.66 1.68 ~. 94
5.54 4. ~5 11.37 6.08
As was noted above, four interpersonal agreement scores were computed for each color, one for each of the conditions under which it appeared. An analysis of variance was performed on these scores. For the interpersonal agreement index, significant main effects were obtained for both independent variables: interpersonal agreement is greater in Dissimilar sets relative to the Similar sets, F(1, 28) = 58.99, p < .001 and in the Dialogue mode relative to the Monologue mode, F(1, 2 8 ) = 48.50, p < .001. The pattern of the statistically significant Set)< Mode interaction, F(1, 23) - - 15.89, p < .001, matches that found for the name-length variable, as is indicated by the means in Table 1. Additionally, and not surprising, a significant main effect is found for Colors, F(23, 23) = 5 . 9 8 , p < .001: colors differ among themselves as to the amount of interpersonal agreement they engender. Neither of the other two first-order interactions (Set X Color and Mode X Color) approaches significance. It is instructive to examine t h e relationship between certain of Brown and Lenneberg's (1954) findings and our own. These investigators have published interpersonal agreement ratings for the 24 referent colors. In their experiment, the color chips were exposed individually. Hence, these names may be thought of as reflecting the intrinsic codability of the colors, uncontaminated by the referent set. Productmoment correlations were computed be-
362
KaAUSS A N D WEINHEIMER TABLE
CORRELATIONS OF BROWN AND LENNEBERG'S INTERPERSONAL AGREEMENT INDEX FOR THE ~4 COLORS USED AND TWO MEASURES I N THIS EXPERIMENT
Treatment
Mean name length
Interpersonal agreement index
Similar-Dialogue Similar-Monologue Dissimilar-Dialogue Dissimilar-Monologue
--. 24 - . 50** --. 43" --. 40*
.80 .62** .55** .55**
*p < .05 ** p < .01
tween these ratings and the mean name lengths found in the present experiment, for each of the four experimental conditions. 2 These values are shown in Table 2. The values of r range from --.40 to --.50 (all significantly different from zero) except in the Similar-Dialogue condition, where it falls to --.24 (n.s.). ( Brown and Lenneberg found a correlation of --.49 between name length and interpersonal agreement.8 Similarly, the correlations were computed between Brown and Lenneberg's interpersonal agreement index and our own for each of our four experimental conditions. These values, displayed in Table 2, range from .55 to .62 (all significant beyond the .01 level) except for the Similar-Dialogue condition, where r-----.80 (n.s.). DISCUSSION
Whether one uses name length or interpersonal agreement as a measure of cod"~It would have been preferable to compare our mean lengths with those found by Brown and Lenneberg. Unfortunately, these investigators did not publish mean length data for individual colors. ~The actual value reported is +.49; Brown and Lenneberg report their results in terms of the brevity of the color name. In our own work we have found it more useful to think of a name as having a mean length, and hence have reversed the sign of this measure.
ability, it is clear that referents have greater codability when they appear in Dissimilar sets than when they appear in Similar sets. It is also the case that codability as measured by interpersonal agreement is greater in the Dialogue mode than in the Monologue mode. Finally, these two variables interact significantly on both measures. The findings for the effects of similarity of the referent set are explicable in terms of a model of interpersonal communication proposed by Rosenberg and Cohen (1964). Briefly, their model considers the process determining a speaker's choice of verbal response in a situation in which he must provide a message which will enable a listener to discriminate one referent from another. It postulates that the speaker samples randomly from his repertoire of names for the referent; names are sampled at a rate proportional to the frequency with which each is applied to the referent in isolation. Having been sampled, the probability that a name will actually be emitted is determined by a comparison between the name's applicability to the referent and its applicability to the other members of the referent set. When the speaker estimates that the name has greater applicability to the referent than to nonreferents, there is a high likelihood that he will emit it. When the sampled name is estimated to be more applicable to the nonreferents, the speaker is likely to reject t h e name and sample a new one. This process continues until a name which meets the comparison criterion is sampled and emitted. Colors similar in hue tend to evoke the same name (Lenneberg, 1961). Hence the Rosenberg-Cohen model would predict that the color names which have the highest probability of being sampled for colors in a Similar set are unlikely to pass the comparison test. The name which ulti-
363
VERBAL ENCODING
mately is emitted will not be the "popular" for that color (since these too often will also be applicable to the other colors in the set), but rather the unusual, low-infrequency names, sampled from the tail of the rank-frequency distribution. For this reason, the names given to such colors will be low on an interpersonal agreement index which is essentially a measure of communality. And, because it so often is necessary to use compound names with qualifiers and color combinations, such names will tend to be relatively long. For colors in Dissimilar sets, however, the "popular" responses have a high probability of being emitted, since the likelihood of their being applicable to the other colors in the set is relatively small. Hence interpersonal agreement will be high and the names given will tend to be relatively short. The effects of the communication-mode variable are somewhat less straightforward. Although large and significant main effects were found for the interpersonal agreement measure, no statistically significant main effect was found for name length. This latter finding is at variance with resuits obtained by Krauss and Weinheimer (1964b), who found large differences in the lengths of names given to novel geometric forms in Monologue and Dialogue conditions. It may be the case that our inability to replicate these earlier results is attributable to differences in the stimulus materials employed. It further strengthens the conclusion, drawn from the work of Brown and Lenneberg (1954) and Lantz and Stefltre (1964), that interpersonal agreement is a more sensitive measure of codability than name length. It is then clear that the way in which a referent is encoded in communication is affected by factors extrinsic to the referent itself. In addition to the factors discussed above, encodi0g should also be
affected by such variables as the information a speaker has about his listener (Ratner and Rice, 1968), the speaker's emotional state (Stoltz and Tannenbaum, 1968), and the relative stress placed on accuracy vs. speed of communication. REFERENCES
BROWN, R. Social psychology. New York: The Free Press, 1965. BROWN, R., AND LENNmSmaC, E. H. A study in language and cognition. 1. abnorm, soc. Psychol., 1954, 49, 454--462. FAI~SWORTn, D. A temporal factor in color discrimination. In Visual problems of color: Symposium. Vol. 2. New York: Chemical Publishing Co., 1961. GLANZER,M., ANDCLAm:,W. H. The verbal loop hypothesis: Conventional figures. Amer. 1. Psychol., 1964, 77, 622-626. JtroD, D. B. Color in business, science and industry. New York: Wiley, 1952. Kaxuss, R. M., AND WEINHEnVmn,S. Changes in reference phrases as a function of frequency of usage in social interaction. Psychon. Sci., 1964, 1, 118-114 (a). KaAuss, R. M., AND WEINrmlMER, S. The effect of feedback on changes in reference phrases. Paper read at meeting of the Psychonomic Society, Niagara Falls, Ontario, Canada, 1964 (b). LANTZ, DELEE, AND STEFrLm~,V. Language and cognition revisited. ]. abn. soc. Psychol., 1984, 69, 472-481. LEHNV-BEnC,E. H. Color naming, color recognition, color discrimination: a re-appraisal. Percept. mot. Skills, 1981, 12, 875-882. RATHER, S. C., AND RICE, F. E. The effect of the listener on the speaking interaction. Psychol. Rec., 1968, 13, 265-268. ROSENBERC, S., AND COHEN, B. D. Referential processes of speakers and listeners. Psychol. Rev., 1966, 73, 208-281. ROSENaERC, S., AND COHEN, B. D. Speakers' and listeners' processes in a word-communication task. Science, 1984, 145, 1201-1208. STOLTZ, W. S., AND TANNENBAUM, P. H. Effects of feedback on oral encoding behaviour. Lang. Speech, 1963, 6, 218-228. ZIPF, G. K. The psycho-biology of language. Boston: Houghton Mif~in, 1935. (Received August 5, 1965)