Effect of context on ratings of personality traitsJ,2

Ab8traet Ss rated 1 personality trait in the context of 2 other

traits. With ordinary judgment instructions, no context effect was found. But if the set oftraits was said to de­scribe a person, the rating of the test trait was displaced toward the value of the context. This positive context ef­fect cannot be explained in perceptual assimilation­contrast terms because of the lack of effect with ordinary judgment instructions. Other interpretations are dis­cussed. Problem

Many tasks require judgments based on a set of stimuli. In this experiment, for instance, certain Ss rated hypothetical persons described by sets of 3 ad­jectives. Theoretical analysis of such tasks aims at relating the response to the scale values (or other parameters) of the separate stimuli. However, merely placing the separate stimuli together into an experi­mental set might produce interaction among them. Indeed, the assimilation-contrast ideas used by Berkowitz (1960), and adaptation-level theory as applied by Podell (1961), presuppose that perception is directly affected by context. For example, the evaluation of a neutral or low stimulus in a set of highs would decrease by contrast. The theoretical analysis would require knowledge of these changed stimulus values, if in fact such interaction did occur.

The present experiment tests directly for such per­ceptual context effects in a person-impression task. It should be specifically noted that only perceptual inter­action, such as might be found in simple judgments of single stimuli, is being called into question. Cognitive interaction, as evoked by semantic inconsistency, for instance, might also occur, but would have a different psychological locus. Method and Proeedure

The S saw cards listing 3 adjectives that described personality traits which he read aloud. After a short pause, the experimenter pointed to 1 of the 3 adjectives which the S then rated under 1 of 2 instruction conditions.

In Condition P, the S was told that the 3 adjectives described a certain person. After reading the adjectives, the S labeled his liking for that person with 1 of 7 verbal categories. The experimenter then pointed to 1 adjective, and the S gave a number from 1 to 20, "corresponding to how much you like that individual trait of the person."

In Condition W, the S was told only that the 3 adjectives were used to describe personality traits; and he rated only the 1 test adjective on the 1 to 20 scale, "corres­ponding to how much you like the traits implied by the adjective."

Psychon. sci., 1965, Vol. 3

NORMAN H. ANDERSON, UNIVERSITY OF CALIFORNIA, SAN DIEGO

ANITA K. LAMPEL, UNIVERSITY OF CALIFORNIA, LOS ANGELES

The stimulus adjectives were from the same 4 sub­lists used in previous work (Anderson, 1965). They are denoted by H, M+, M-, and L, standing for highly favorable, moderately favorable, moderately unfavor­able, and highly unfavorable.

The 8 types of experimental set were from a 2 by 4 design, with 2 values of test adjective, and 4 values of context. The test adjective, which was to be rated by the S, was an M+ or an M-. The contexts were pairs of adjectives: HH, M+M+, M-M-, or LL. The 3 adjectives were in random order on each card so that, in particular, the S had no clue about which adjective was to be rated until after he had read them all.

Each S received 2 sets of each type. A first stimulus replication was constructed by random choice, without replacement, so that no S saw the same adjective twice. To balance particular test and context stimuli, 3 additional stimulus replications were also constructed, separately for M+ and M-, with test and context recombined by a 4 by 4 latin square. The stimulus replication factor was not significant in any analysis, indicating that the results are not peculiar to the stimuli used.

There were 6 initial practice sets that covered the range of scale values. In addition, 8 filler-anchor sets, 4 each of HHH and LLL, were included. They were shuffled together with the experimental sets, separately for each S. Ss were introductory psychology students, with N's of 20 and 40 for Conditions P and W, run individually, and randomly assigned to the cells of the complete design. Re8ult8

Figure 1 plots the mean rating of the test adjective as a function · of the value of the context. For Condition P, in which Ss formed an impression of a person, it is clear that context has a marked effect. Comparison with the ratings for the homogeneous sets, M+M+M+ on the upper curve, and M-M-M- on the lower curve, shows that the rating of the test adjectives is uniformly dis­placed toward the context. This will be called a positive context effect, a term chosen for its neutrality as a purely data-descriptive term.

Statistical analyses were made separately for the M+ and M- test adjectives, for which the design allowed within-subject error terms. For Condition P, F(3, 48) = 24.05 and 8.88 for the M+ and M- test condi­tions, respectively.

Condition W, even with twice as many Ss, did not show a reliable context effect: F(3, 108) = 1.46 and 1.44 for the M+ and M- tests, respectively.

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14

13

12

c.o z i= I I <t 0: UJ > i= 10

" UJ ..., " <t 9 >-<J> UJ >-z 8 <t UJ

'"

- CONDITION P

0---0 CONDITION W

VALUE OF CONTEXT

M+TEST

M+ TEST

M-TEST

M-TEST

Fig. 1. Mean rating of test adjective as a function of context.

A previous, quite similar experiment, which included also Hand L test adjectives, supports the aboveo The data for Condition P were much the same as those reported here. For Condition W, with N=40, 3 of the 4 F ratios for test adjective were nonsignificanto Although the F ratio for the M+ test was marginally significant, the shape of the curve was directly opposite to that in Figo 1, and the result may have been due to confounded effects of particular adjectives since the design did not include the present latin-square balancing 0

Although interpretation of a negative result is always risky, the above data seem to give a reasonably firm basis for claiming that there is little or no context effect in Condition W 0

Disf'u 8slon The main theoretical problem presented by the data

is to explain the strong positive context effect in Condition Po The main conclusion allowed by the data is that this context effect cannot be explained, even in part, in perceptual assimilation-contrast termso Such an explanation would assume that the context alters the perception of the single stimulus 0 If this were so, a context effect would be expected in Condition W where little or none was observedo It would seem, therefore, that caution is needed in applying assimilation-contrast ideas to impression formation or social judgmenL

As a partial digression, the disagreement between the present data and those reported by Berkowitz (1960) requires commenL Although the discrepancy might be due to the difference between simultaneous and serial presentation, the likelihood is that Berkowitz' data contain an extraneous response tendency 0 The Ss there judged each of a sequence of traits, of which the first 7 were either all high or all low in value and

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constituted the context, and the last 4 were all medium in value and constituted the test stimuli 0 A tendency to use the response categories equally often (Parducci, 1965) would, with such sequential responding, produce an apparent "contrast effect" in the absence of any actual psychological contrasL If the present data are a safe guide, replication without requiring judgments of the context stimuli would reduce or eliminate the negative context effect that Berkowitz reported for the analog of the present Condition W, as well as produce a positive context effect in the analog of the present Condition Po

Two other interpretations of the positive context effect in Condition P may now be discussedo On the face of it, the results imply that the value or meaning of the test word has changed as a consequence of the impression formation processo Certainly, it seems no more than common sense that semantic interaction will occur in the impression task, and the data are in qualitative agreement with the view that the S selects out shades of meaning that increase the consistency between test and contexto

On the other hand, after the single adjectives have been integrated into an impression, they may no longer have separate meanings, at least in an ordinary senseo The S's rating of a particular adjective would be considered as a composite of his liking for that trait per se, and of his liking for the person 0 This would also account for the data at a qualitative leveL

More specific assumptions would bring this last interpretation into quantitative formo If the impression of the person is an average of the values of the separate traits (Anderson, 1962), and if the rating of the test trait is a weighted average of the S's liking for that trait by itself, and of his liking for the person, then the test-by-context interaction in the analysis of variance is predicted to be zeroo This particular test has relatively low power in the present design since its error term includes context variability. For what it is worth, however, the observed interaction wasnonsigni­ficant, F(3, 48) = 0.98. This formulation may thus deserve more serious consideration.

References Anderson, N. H. Application of an additive model to impression

formation . Science, 1962, 138,817-818. Anderson, N. H. Averaging versus adding as a s timulus-combination

rulein impression formation. J. expo Psychol., 1965, 70, in press . Berkowitz, L. The judgmental process in personality functioning.

Psychol. Rev., 1960,67, 130-142. Parducci, A. Category judgment: A range-frequency model. Psychol.

Rev., 1965,72, in press. Podell, J. E . A comparison of generalization and adaptation-level

as theories of connotation. J. abnorm. soc. P sycho l., 1961 , 62,593-597.

Notes 1. We are much indebted to Shermhn L. Guth for suggesting the present experiment by aSSigning a related one in an undergraduate class, and for several valuable discussions. 2. This work was supported by NSF' G'ant GB-1470.

Psychon. Sci. , 1965, Vol. 3