The creation of uncertainty in the influence process: The roles of stimulus information and...

European Journal of Social Psychology, Vol. 23,17-38 (1993)

The creation of uncertainty in the influence process: The roles of stimulus information

and disagreement with similar others

CRAIG McGARTY, JOHN C. TURNER, PENELOPE J. OAKES and S. ALEXANDER HASLAM Department of Psychology, Australian National University, Canberra, Australia

Abstract

Social and cognitive psychologists have conceptualized judgemental confidence (how strongly a person holds the belief that some judgement is correct) as being proportional to the amount of evidence in favour of a response. Festinger (1950) argued that there are two separate processes by which uncertainty (the inverse of confidence) can be reduced. These two processes are physical reality testing (the perceptual processing of stimulus information) and social reality testing (reliance on other people to resolve particularly ambiguous situations). However, there is surprisingly little direct evidence that uncertainty is either reduced or increased by the responses of other people. In two experimental tests ( N = 74 and N = 83) it was found that disagreement increased uncertainty andagreement tended to reduce uncertainty. In a thirdexperiment ( N = 63) it was found that disagreement only increased uncertainty when stimulus information was limited, but that agreement generally reduced uncertainty. The results challenge Festinger s model of uncertainty reduction and support a self-categorization theory account.

INTRODUCTION

Over the last 60 years many important theories of social influence have recognized the crucial role played by uncertainty (the formation of social norms (Sherif, 1935, 1936); the theory of informal social communication (Festinger, 1950); the theory of social comparison processes (Festinger, 1954); the genetic model of social influence (Moscovici, 1976); and self-categorization theory (Turner, 1985)). Despite its apparent theoretical importance, however, there is very little direct empirical evidence as to what determines uncertainty, especially as it relates to the influence process.

Addressee for correspondence: Craig McGarty, Department of Psychology, Australian National Univer- sity, GPO Box 4, Canberra, ACT 2601, Australia.

0046-2772/93/010017-22$16.00 0 1993 by John Wiley & Sons, Ltd.

Received I 1 November 1991 Accepted 9 May 1992

18 C. McGarty et al.

In this paper we seek to examine the relationship between uncertainty and the influence process.

The term uncertainty is widely used within the field of social psychology (as it is within general psychology). Some usages treat uncertainty in a formal sense as variability, disorder and a lack of constraints on responses (the last usage is from information theory (Shannon and Weaver, 1949, cited in Jones and Gerard, 1967). This is the usage adopted by authors such as Tversky and Kahneman (1974; Kahne- man, Slovic and Tversky, 1982) when talking about judgement under uncertainty. In this sense uncertainty is a probabilistic statement about the possibility of accurate prediction (Smithson (1989) has argued that probability and possibility are two alternative forms of uncertainty that social psychologists must consider). However, the more customary psychological usage of the term refers to the lack of strength of some belief. These two ideas are not necessarily distinct. The more response alternatives we have, the less confident we may be in choosing any one of them.

Given that there are two related usages of the term uncertainty we will refer to the inverse of uncertainty, that is, confidence or subjective validity (Festinger, 1950, 1954) while seeking to define the psychological aspects of the concept. There is a wide-ranging consensus that confidence or subjective validity is the degree to which someone believes that a cognition is correct (i.e. is believed to match objective underlying conditions). Where such beliefs are expressed as responses we can refer to this idea as judgemental conjidence. Judgemental confidence is an operationalization of subjective validity. The theoretical consensus about confidence extends to the idea that we should be more confident in a response to the extent to which we have evidence in favour of that response. This idea can be seen in work on decision processes in visual perception (e.g. Vickers, Smith, Burt and Brown (1985) where confidence was defined as the balance of evidence in favour of a response). Numerous studies in social and cognitive psychology show that confidence in a response is proportional to the amount of evidence in favour of it. So, for example, stimuli which are of low ambiguity tend to be judged with high confidence (for a review of the social psychological research see Tajfel, 1969; for a review of the cognitive research see Vickers et al., 1985). Jones and Gerard (1967, pp. 124125) linked the mathematical definition of uncertainty (in terms of number of alternatives) with the psychological conceptualization in terms of evidence (or information) to argue that people are motivated to reduce uncertainty by seeking information (information dependence) from the physical or social environments.

We must distinguish immediately between judgemental confidence and more general feelings of competence in one’s abilities. Often the term subjective validity is used to refer to a basal, global and continuing level of confidence or perceived self-competence. There is a two-way street between local and global confidence but they need not be identical. One way of conceptualizing the relationship would be to understand judgemental confidence as the case-by-case expression of global confidence. The implication is that judgemental confidence is a function of both global confidence (or perceived self-competence) and local factors.

The importance of the concept of confidence for social psychology derives from its role in the influence process (although the reduction of uncertainty also underlies theories of attribution and cognitive consistency - see Jones and Gerard, 1967). Subjective uncertainty creates a predisposition to be influenced. The implication which has been drawn from this by many social influence researchers is that social

Uncertainty and disagreement 19

influence exists to achieve uncertainty reduction. Although Moscovici has challenged the view that uncertainty (more precisely uncertainty reduction) deserves it pivotal status in the study of influence (Moscovici, 1976; Moscovici and Faucheaux, 1972), he acknowledges that everybody accepts that people are more likely to be influenced if they are uncertain (Moscovici, 1976, p. 53; data actually demonstrating this are described by Krech, Crutchfield and Ballachey, 1962). On the other hand, while it has been traditional to argue that influence involves the reduction of uncertainty (uncertainty being an aversive state), Moscovici (1976) has argued that uncertainty is created by the influence process (a point made explicitly by Asch (1952, 1956) and Krech et al. 1962). What is more, this uncertainty can be created when judging stimuli which are objectively unambiguous (as in the Asch paradigm). Uncertainty can arise as a social product of disagreement with others which suggests or creates social conflict. There has, so the argument goes, been a lack of communication between theorists and researchers of the influence process. Whereas theorists have argued that social influence is a product of the reduction of uncertainty, what experi- menters have actually been doing in the laboratory is creating uncertainty.

For Moscovici then, variations in confidence are effects rather than causes of the influence process. This stands in stark contrast to the view alluded to earlier that the influence process exists to reduce uncertainty about what the stimulus is and how to respond to it. In short, we have on the one hand, a view that agreement with a reference group (consensus) should reduce uncertainty and, on the other, that disagreement should create uncertainty.

It is with these processes that we are concerned in this paper. Under what conditions is uncertainty created or reduced? It seems reasonable that uncertainty should vary with the influence process but it is nevertheless true that despite the prominence assumed for uncertainty there is almost no evidence which can be interpreted as directly testing the effects of agreement or disagreement on confidence levels (and even less evidence which is reported in a reliable form). As Insko, Drenan, Solomon, Smith and Wade (1983) conclude, the empirical evidence for the roles of the concern for being liked, and the concern for being right in conformity is largely circumstantial. They also contend that the concern for being right (which is the basis of confidence) has received even less formal attention (Tesser, Campbell and Mickler (1983) also point to the paucity of research on the creation of self-doubt).

As we mentioned earlier, influence theorists have been interested in uncertainty as a covariate (whether cause or effect) of the influence process. The basic findings linking influence to confidence are described (albeit briefly) by Krech et al. (1962). People who express more confidence in theirjudgements are less likely to be influenced by others (Krech et al., 1962, p. 510). This is also consistent with research on persua- sion which has shown that people with high ego-involvement on an issue are less likely to be persuaded (Sherif, Sherif and Nebergall, 1965). More interestingly, people who are influenced do not show a decrease but an increase in confidence (Krech et aZ., 1962, p. 519).

There are three classes of indirect evidence which can be interpreted as showing the role of uncertainty in the influence process (the area has been reviewed by Allen (1965) and Jones and Gerard (1967) but research showing resistance to influence, e.g. Allen (1975) is just as relevant). First, there are numerous studies showing variations in the strength of influence which indicate that influence is stronger when the task is difficult, the stimuli are ambiguous, the group is believed to be


highly competent, and the subject has no social support for his or her own views. All of these manipulations could be expected to involve low confidence. There is less influence when the task is not difficult, the stimuli are unambiguous, the subject believes him- or herself to be competent, the subject believes the issue to be important, and the subject has social support for his or her own views. All of these manipulations could be expected to involve high confidence. It is reasonable to conclude that influence is associated with low confidence and that independence is associated with high confidence. This conclusion is based on extensive evidence and is summarized in reviews by Allen (1965, 1975), Allen and Wilder (1977), Jones and Gerard (1967) and Kiesler and Kiesler (1969).

The second class of evidence which relates to the effects of agreement and disagreement on confidence includes studies where subjects’ opinions were validated or invali- dated by the experimenter (Crutchfield, 1955; Di Vesta, 1959; Jones, Wells and Torrey, 1958; Mausner, 1954). These manipulations are manipulations of competence but since competence was manipulated through validation we can conclude that when subjects receive strong social support they tend to be more resistant to influence following disagreement.

The third class of evidence is work showing physiological changes (a higher level of arousal) in subjects who were exposed to influence attempts. In general, disagreement has been shown to engender physiological arousal (Back and Bogdonoff, 1964; Gerard, 1961, 1964b; Gerard and Greenbaum, 1962; Smith, 1936 cited by Jones and Gerard, 1967). While such effects are suggestive of changes in confidence they are in no sense direct measures. Such arousal could result from uncertainty over the correctness of a response, or it could result from a fear of the disapproval which could be experienced after giving a response that the group disagrees with. We have no way of separating these two on the basis of the results reported.

It is precisely because uncertainty varies as a function of the influence process that there is very little clear evidence showing variations in it due to agreement and disagreement. The reasons for this lack of data on such a crucial issue are actually quite straightforward. The effect of influence per se is normally confounded with the effects of agreement and disagreement on confidence (remembering that influence is by definition the chief dependent variable in these studies). In order to measure the effects of agreement and disagreement on confidence we need the following: (a) a response, (b) a measure of confidence, (c) exposure to some other relevant opinion, and (d) a measure of confidence in the original response. It is the last of these requirements which is normally lacking. We need trial-by-trial measures of changes in confidence which are not confounded with changes in the response because, as Krech et al. (1962) illustrate, confidence can remain high even though the response has changed. Where confidence (or related measures) has been considered it is usually measured as a post-test expression by the subjects (Allen and Levine, 1968; Deutsch and Gerard, 1955; see also Gerard, 1964a; Nemeth and Wachtler, 1983; Tesser et al., 1983) or is inferred by the experimenter (Asch, 1952, 1956). Other studies which have measured confidence on a trial-by-trial basis have measures which are confounded with social influence or other variables (Brodbeck, 1956; Festinger, Gerard, Hymovitch, Kelley and Raven, 1952; Gerard and Green- baum, 1962).

There are difficulties of interpretation in the studies which have measured confidence on a trial-by-trial basis. Festinger et al. (1952) simply fail to report the confi-

Uncertainty and disagreement 2 1

dence data (after commenting on difficulties of interpretation similar to those mentioned above). Brodbeck (1956) sought to use confidence as an independent variable. We can interpret her descriptions of her pretest procedure as suggestive evidence only of variability in confidence following disagreement (rather than evidence of a decrease).

The only study that we have been able to locate which may show direct variations in confidence due to agreement and disagreement was reported by Gerard and Green- baum (1962). They used the Crutchfield paradigm with a group of confederates who gave erroneous responses. During the course of the experiment one of the confederates switched to giving correct responses on the critical trials (while the others continued to give erroneous responses). They found that there was an increase in confidence following the switch of the confederate from disagreement to agreement. Gerard and Greenbaum (1962) do not report the levels of conformity in this experiment but this result does seem illustrative of an increase in confidence following agreement. They also found that confidence tended to decrease over the course of the experiment. However, we should be cautious about this interpretation as the experiment involved confounds of influence, agreement and stage effects.

We have therefore a state of affairs where many researchers believe in relationships which have never been demonstrated in ways which could be considered methodologi- cally sound. There are obvious dangers in allowing crucial assumptions to remain untested. Of course, there are many assumptions in social psychology which have attracted very little empirical research but this lack of research is unacceptable where there is continuing theoretical controversy about the assumptions. However, in addition to this general issue we have the current concern that if we wish to examine variables which mediate the strength of the effects of agreement and disagreement on confidence, we must first of all establish the existence of those effects. We set out to do this in Experiment 1.

EXPERIMENT 1

In Experiment 1 we sought to test the effects on confidence of agreement and disagreement with a reference group. We adopted a design of the form advocated above with a judgement, a confidence rating, exposure to the group’s opinion, and a new confidence rating. We decided to use a perceptual task where there was an objectively correct answer but where it was difficult for subjects to be certain of that answer. We manipulated agreement and disagreement and whether the reference group was similar to self and appropriate for comparison for the task at hand.

The purpose of the last variable was to test whether the similarity of the group mediated variations in confidence (this relates to the first class of evidence on the relationship between uncertainty and influence). The simplest way to create a dissimi- larhnappropriate reference group in a perceptual judgement task was to inform the subjects that the group was comprised of visually impaired people (a suggestion made by Allen and Levine, 1968). Visually impaired people are dissimilar and inap- propriate for comparison because they would be expected to be less competent. We expected that the hypothesized reduction in confidence due to disagreement and the hypothesized increase in confidence due to agreement would be weaker when the reference group was perceived as less competent. This hypothesis could


be derived straightforwardly from the theory of social comparison processes (Fest- inger, 1954) or self-categorization theory (Turner, 1985). In summary, we hypothesized: (1) Confidence will increase following reference group agreement. (2) Confidence will decrease following reference group disagreement. (3) These effects will be weaker when the reference group is perceived to be different from self.

Method

Design

The study had a 2 X 2 X 2 design with two between-subjects factors and one within- subjects factor. The between-subjects factors were feedback from group (agreement versus disagreement) and similarity of group (similar versus dissimilar); the within- subjects factor was confidence stage (before and after feedback).

Subjects

The subjects were 74 introductory psychology students at Macquarie University in Sydney, Australia (male and female subjects were used).

Procedure

On arrival at the experimental session the subjects seated themselves at a computer and were presented with a set of instructions describing the task (the actual instructions varied with conditions and they will be presented below). Essentially the task was to estimate the number of dots appearing on an area of the screen (150 by 150 pixels). Each dot was 4 X 4 pixels. The dots in each stimulus were presented sequentially on the screen until the total number of stimuli had been presented. A dot was presented every 1/60th of a second until the total had been presented. In this way the subjects had two indices of the number of dots (1) the perceptual information displayed and (2) the amount of time to build the display. Each complete stimulus was displayed for one second. There were 16 different stimuli which ranged (in equal intervals) from 39 to 159.

After the end of the presentation time the stimulus was erased and a prompt appeared on the screen: ‘Number of dots’. The subjects then typed in a number of dots between 20 and 180. After their responses had been entered another prompt appeared, inquiring ‘How confident are you?’ and a scale from 1 to 100 with 1 labelled ‘completely unconfident’ and 100 labelled ‘completely confident’. The subjects then typed in a value between 1 and 100 representing their confidence. After they had pressed the return key the computer presented the subjects with a feedback score after which they were again asked how confident they were.

Feedback

This factor had two levels: agreement and disagreement. The subjects were told that they would receive feedback from a group of other people who had completed the same task in the previous year. The feedback was purportedly the average of these people’s response to the same stimulus. In this way we hoped to provide a


reference group of similar others that the subjects might generally expect to agree with their own judgements. In fact the feedback they were given was a random response linked to their own judgement, which either differed with their response by a small amount (agreement) or by a large amount (disagreement). The feedback was presented immediately after the subjects had given their confidence in their judgement. The feedback was presented as a single number expressing the purported average response of the group. They were then asked ‘How confident are you now?’

Agreement In this condition the subjects were given feedback which was highly congruent with their own response. The feedback given was the subject’s own response plus a random number in the range - 10 to 10.

Disagreement In this condition the feedback was based on the subject’s own response. The feedback score differed from the response by 27 plus a random number in the range 0 to 20. Whether the number was greater or less than the subject’s response was randomly determined for each trial (unless this resulted in a feedback score outside the range 20 to 180, under which circumstances the alternative feedback score was selected, i.e. if the subject’s response was 150 and the feedback score was 192 [ 150 + 421 then the score would be adjusted to 108 [ 150 - 421).

Similarity of group

There were two levels of the similarity of group factor: similar and dissimilar. The similar group was described as being comprised of fellow introductory psychology students (PSY 103 was the course code). The dissimilar group was described as a group of visually impaired people.

Post-test

At the completion of the experiment the computer asked five follow-up questions. These were measures of perceived group competence (on a scale from 1 to loo), perceived similarity of group to self (yes or not), perceived self-competence (on a scale from 1 to 100)’ whether subjects thought the group was real, and whether subjects doubted the reality of the group during the experiment (both yes or no responses).

DebrieJing

On the completion of the task the subjects were questioned as to what they thought the purposes of the experiment were, and whether they thought the responses had been provided by real people. They were then completely debriefed about the experiment.

Results

Confidence

The results for confidence are shown in Table 1. It can be seen that disagreement produced a decrease in confidence and that agreement produced an increase in confidence. This interaction was in fact significant (F(1,71) = 13.5, p < 0.001). Post


hoc comparisons by the Bonferroni method, however, revealed that the decrease in confidence due to disagreement was significant (62.0 versus 57.6, t(71)= 3.3, p < 0.01) but that the increase in confidence due to agreement was not (64.6 versus 67.1, t (71) = 1.9, ns). No effects involving the similarity of group factor approached significance.

Table 1. The effects of feedback and group similarity on confidence: Experiment 1

Feedback Agreement Disagreement

Group Conf. before Conf. after Conf. before Conf. after

Normal 64.7 65.7 62.7 56.9 Visually impaired 64.4 68.4 61.2 58.1

Post-test measures

Contrary to expectations, perceived group competence did not differ between the similar and dissimilar group conditions and the weak trend was in the wrong direction ( M (similar) = 57.7 versus M (dissimilar) = 64.8, F(1,70) = 2.04, ns). This suggests that the manipulation was unsuccessful. Furthermore, perceived similarity of group was not reflected in a difference in the proportion of subjects who saw the normal group as similar to themselves (22 out of 36 = 0.61) and the proportion who saw the visually impaired group as similar to themselves (23 out of 38 = 0.61).

The analyses for perceived self-competence and perceived group competence yielded differences on the feedback factor. Subjects in the agreement condition regarded the group as more competent than did subjects in thedisagreement condition ( M (agreement) = 70.0 versus M (disagreement) = 51.9, F(1,70) = 24.0, p < 0.001). Similarly, self-competence was higher in the agreement than the disagreement condition ( M (agreement) = 65.0 versus M (disagreement) = 53.0, F (1,70) = 1 1.5,

The next question to consider was suspicion about the deceptions. In the agreement condition 17 (0.44) subjects said that the reference group was not composed of real people and 22 said that it was (0.56). Of the 39 subjects in the agreement condition, 11 (0.28) reported that they had doubts about the reality of the group during the experiment. In the disagreement condition 10 out of 35 subjects thought that the group was not comprised of real people, and 12 reported having such doubts during the course of the experiment. We analysed the results with and without subjects who reported having doubts during the course of the experiment. There were no new significant interactions or main effects when response on the doubt question was used as a factor. The same simple effects were significant with and without subjects who reported doubting the reality of the group. The implication would seem to be that either such doubts did not affect the results or our questions about doubt were unable to pick up the differences.

p < 0.001).

Discussion

The results do not provide clear support for hypothesis 1 that agreement should increase confidence. They do support hypothesis 2, that disagreement should increase


uncertainty. There was no evidence here to support hypothesis 3 that perceiving the group to be different from the self moderates the impact of agreement and disagreement. We can conclude that our concern about the absence of experimental variations in confidence due to agreement and disagreement in the literature is vindi- cated. This is especially true given that we have not been able to find a significant increase in confidence due to agreement.

The manipulation of similarity of the group was not effective. We find this surpris- ing, but given that we were unable to vary the perceived competence of the group (with what seemed to be a strong and relevant manipulation) we cannot interpret these results as a test of hypothesis 3. Subjects may not have believed or understood the description of the visually impaired group (they were not told the extent of the impairment), or they may have expected the mean response of such a group to be a reliable estimate, even if the individual responses were not (given that the subjects were given no information about response variability this was a reasonable position to adopt). The effects showing that subjects exposed to agreement have higher self-and group competence ratings than subjects exposed to disagreement are interesting. They suggest that subjects attribute agreement to the possibility that both the group and themselves are correct, but they attribute disagreement to the possibility that either the group or themselves could be wrong (Krech et al., 1962; Turner, 1985).

EXPERIMENT 2

Given the puzzling lack of a significant agreement effect in Experiment 1 we decided to replicate this study. The only changes were the number of dots per stimulus (which was increased), and some changes in the post-test questions. The manipulation of the similarity of the reference group was included again.

Method

Subjects and design

The subjects were 83 introductory psychology students at Macquarie University (male and female subjects were used). The study’s design was identical to that of Experiment 1.

Procedure

The measures, procedure and independent variables were identical to those in Exper- iment 1 with the following exceptions. The number of dots per stimuli varied from 159 to 279 and the response range 140 to 300 was used. The post-test questions relating to the reality of the group, and doubts about the group were not included. The question about the effects of perceived agreement and disagreement took the following form: ‘Do you think these people were similar to you in their responses? (yes or no)’. This question was included as a means of gaining insight into the subjects’ experience of agreement and disagreement during the task.


Results

Conjidence

The confidence results are shown in Table 2. Again the results show an increase in confidence due to agreement and a decrease in confidence due to disagreement. However, as in Experiment 1 similarity of group produced no effects. The interaction between confidence stage and feedback was highly significant (F(1,74) = 36.5, p < 0.001). Multiple comparisons by the Bonferroni method reveal that both the increase in confidence due to agreement (Ms = 56.8 versus 61.5, t (74) = 3 . 6 , ~ < 0.01) and the decrease in confidence due to disagreement were significant (Ms = 56.8 versus 50.7, t (74) = 4 . 9 , ~ < 0.01).

Table 2. The effects of feedback and group similarity on confidence: Experiment 2

Group


Conf. before Conf. after Conf. before Conf. after

Normal 56.6 60.9 56.8 48.9 Visuallv imDaired 56.8 61.9 56.8 52.4

Post-test measures

We had post-test measures for 81 subjects (some post-test data was lost from computer files). Analysis of variance revealed no difference due to the similarity of group factor in perceived group competence (F(1,74) < 1, ns). The effects of agreement and disagreement on perceived group and self-competence were the same as those in Experiment 1, Subjects exposed to disagreement perceived themselves to be less competent than subjects exposed to agreement perceived themselves to be ( M (agreement) = 64.0 versus M (disagreement) = 51.1, F(1,74) = 9.1, p < 0.01) and they also perceived the group to be less competent (A4 (agreement) = 70.9 versus M (disagreement) =54.5, F(1,74) = 1 6 . 1 , ~ < 0.001).

Of 40 subjects in the agreement condition eight said they believed the group’s responses were different from their own and 32 said the group was similar. Of 41 subjects in the disagreement condition 19 said that the group’s responses were different from their own. The proportion is significantly higher in the disagreement con- ditionk2(1)=5.1,p<0.05).

Discussion

In two experiments we have shown that disagreement reduces confidence and in Experiment 2 we have also shown the predicted significant increase in confidence due to agreement. We can therefore be relatively confident about the effects of agreement and disagreement on uncertainty. Furthermore, the results showing that perceived self- and group competence are lower following disagreement support the view that disagreement is attributed to the possibilities that either the self, the group or both are wrong (Krech et al., 1962; Turner, 1985).

However, the similarity of group variable has been unsuccessful in producing


effects, and can be said to fail the manipulation checks in that it did not produce different levels of perceived competence. We therefore dispensed with this variable (for current purposes) in a final study which focused on the single versus dual-process models of uncertainty reduction and production.

EXPERIMENT 3

Having established the effects of agreement and disagreement on uncertainty we can now consider other variables which mediate these relationships. Following on from the perspective advanced in the Introduction, it would seem reasonable that if confidence is a function of the evidence we have in favour of a response then stimulus information should be an important factor.

The first major perspective advanced on these issues was Festinger’s (1950) theory of informal social communication (and it could be argued that this approach has remained the mainstream perspective). Festinger postulated that people have a basic drive to have accurate opinions. He suggested that they are confident (have high subjective validity in their beliefs) to the extent that they have direct, physical means of testing them (physical reality testing). If we are uncertain about how heavy something is we can reduce this uncertainty by weighing it. In the absence of direct physical tests we turn to other people to test and validate our opinions (social reality testing). If we cannot weigh something (because it is bolted to the ground) we may ask some expert how much the thing weighs (or look it up in a book). An important part of this theory is that social means of validation are definitely secondary; we only use them in the absence of physical means. The theory deals with uncertainty reduction through agreement in quite a direct manner. We turn to other people to reduce uncertainty when we have very little objective, physical information (or limited access to that information).

The theory does not deal directly with the production of uncertainty through disagreement. However, Festinger (1954) also proposed a theory of social comparison processes. In this theory he postulated that the same drive which leads people to seek to have accurate opinions also makes them oriented towards having accurate appraisal of their abilities. The theory of social comparison processes states that: ‘For both opinions and abilities, to the extent that objective physical bases for evaluation are not available, subjective judgements of correct and incorrect opinion . . . depend on how one compares with other persons’ (Festinger, 1954, p. 119).

Thus to the extent that uncertainty is a subjective judgement that some opinion is incorrect then, we can expect that social comparison in the form of disagreement should create uncertainty under conditions of low physical reality testing. This point was derived by Festinger from the theory in these terms: ‘The availability of comparison with others whose opinions or abilities are somewhat different from one’s own will produce tendencies to change one’s evaluation of the opinion or ability in question’ (Festinger, 1954, p. 122).

If we read ‘opinions . . . somewhat different from one’s own’ as disagreement and ‘one’s evaluation of the opinion’ as confidence then we must accept that Festinger predicted that disagreement produces uncertainty under conditions of social reality testing.

In any case, the idea that disagreement can create uncertainty fits in with the


experimental tradition that other people are used as sources of information in relevant situations. To the extent to which they disagree with us then we have less evidence in favour of our response and we should therefore be uncertain (Gerard and Green- baum’s (1962) treatment of uncertainty is close to this idea). From Figure 1 we can see that Festinger’s model suggests social information only has an effect where information is limited, in which case agreement increases confidence and disagreement decreases it.

Insko et al. (1983) reported some data which bear on this point. They investigated the effect of the concern with being right (related to informational influence or dependence) on conformity. They compared conformity levels under conditions where subjects believed that the answer could be objectively determined with conditions where the subjects believed there was no objectively correct answer. They found higher conformity when the subjects believed there was an objectively correct answer. One explanation they suggested for this was that subjects may have used both a consensus and a correspondence (i.e. correspondence between the response and observed reality) criterion for truth. A consensus was seen as informative when there was an objective answer to the question. In other words, the social consensus was taken as evidence of the underlying physical reality. The direction of the effect is not what we would expect on the basis of Festinger’s (1 950) theory of informal social communication.

Moscovici (1980,1985) suggested a perspective on the difference between majorities and minorities in the creation of self-doubt. He suggested that majorities increase attention to their response (raising a concern for being linked, effect dependence or normative influence which leads to compliance by means of a comparison process) but minorities increase attention to the stimulus (due to a concern for being right, informational dependence or influence which leads to conversion via a validation process). Tesser et aZ. (1983) tested aspects of this perspective using a task involving the discrimination of sounds. They used conditions of high pressure (the prior response of three other people) and low pressure (one other person). Their dependent variables were attention to the stimulus (actually accuracy) and self-doubt (measured in a post-test questionnaire). It was found that low social pressure produced moderate levels of attention to the stimulus but that high social pressure produced a bifurcation with either high or low attention to the stimulus. Furthermore, under high social pressure there was a negative association between attention and self-doubt so that more attention to the stimulus was associated with less self-doubt. Tesser et al. (1983) interpret this as support for Moscovici’s views (if high social pressure is equated with majority influence). Since Tesser et aZ.3 measure of attention was actually one of accuracy the interpretation of this result is not necessarily strong support for Moscovici’s perspective. We should expect to find that accuracy is associated with confidence (Vickers et al., 1985).

Nevertheless it is clear from the studies by Insko et al. (1983) and Tesser et al. (1983) that uncertainty reduction and production should be mediated by information about the stimulus. A further perspective on this issue is provided by self-categorization theory (Turner, 1985, 1991; Turner, Hogg, Oakes, Reicher and Wetherell, 1987; Turner and Oakes, 1989).

Self-categorization theory rejects the rigid dichotomy between physical and social reality testing. On the contrary, the theory emphasizes the social-normative aspects of uncertainty reduction and production. Rather than there being two opposed pro-


cesses, there is one integrated process with social-normative and cognitive aspects. The social-normative process is that uncertainty is reduced through agreement with others who are similar in a relevant way, and it is increased by disagreement with similar (relevant) others. This is not independent of the cognitive activity that we undertake with respect to some situation but is fully integrated with it. We are only affected by the agreement or disagreement of relevant other people. That is, we only take into account the views of people who are interchangeable with ourselves in terms of the current circumstances (strictly, fellow ingroup members).

The reason we do this is simply because we take those other people’s responses as informative of the underlying reality. Where those other people are not believed to be competent or relevant (i.e. they are ill-informed or lying and cannot be categor- ized as identical to self) then we would expect the individual to attempt to resolve the ambiguity by cognitive activity. Even so, the individual is still acting as a member of society, in applying internalized social norms to resolve uncertainty. For example, subjects in the Asch paradigm might seek to resolve the disagreement by picking up a ruler and measuring the line lengths, but in doing so they would be accepting the ruler as a material expression of an existing social consensus (Moscovici, 1976). It is important to recognize here that the social consensus is not normally opposed to underlying reality (if it were, it would be maladaptive, dysfunctional and would be rejected) but our cognition is constantly engaged in seeking appropriate comparison others who will help us to validate or invalidate our beliefs. In short, uncertainty reduction and production are simultaneously both social-normative and cognitive and if anything the social-normative aspect is primary because there is no such thing as the isolated, asocial individual (cf: Turner and Oakes, 1986).

These and other observations have led Turner (1985, 1987) to make the following hypotheses on the basis of the self-categorization theory of social influence (see Turner and Oakes (1989) and also Abrams and Hogg (1990).

(1) Confidence is a direct function of the extent to which similar (relevant) people are perceived, expected or believed to agree with one’s own response.

(2) Conversely, subjective uncertainty is a direct function of the extent to which similar others are not perceived, expected or believed to respond similarly to oneself in the same stimulus situation.

(3) Uncertainty-reduction may be accomplished by: (a) the attribution of the disagreement to perceived relevant differences between self and others, and/ or (b) the attribution of the disagreement to perceived relevant differences in the shared stimulus situation and/or (c) mutual social influence to produce agreement.

The clear prediction that we can derive from 1 above is that in the absence of ceiling effects (i.e. assuming there is some existing uncertainty) consensual validation (agreement) should produce uncertainty reduction under conditions of both high and low stimulus information. Furthermore, we would expect, following 2 that disagreement will produce uncertainty. The prediction of uncertainty production is modified, however, by the predictions concerning uncertainty reduction in 3. Under conditions of high information uncertainty reduction can be achieved by paying more attention to the stimuli. This invokes hypothesis 3a that the disagreement is attributed to differences between the self and others (in short ‘they’re wrong!’). This is not possible where information is limited and uncertainty increases as there


is no countervailing process of uncertainty reduction (to the extent to which 3a, 3b, or 3c are not available). With high information the group is more likely to be rejected because its responses do not match the correspondence between the stimulus and the subject’s own percepts, a correspondence which has been validated by a lifetime of prior social interaction. Variations in information can also lead to differences in whether subjects attribute the disagreement to differences in stimulus information 3b. Where subjects have high information they may attribute the disagreement to the possibilities that the disagreeing group had less information, or paid less attention to that information.

It is important to spell out why a main effect is postulated for agreement (in the absence of ceiling effects) but an interaction is postulated for disagreement. Agree- ment produces confidence, and disagreement produces uncertainty but (if the judgement is important) it also motivates aprocess of uncertainty reduction. Under normal circumstances there is no equivalent countervailing process following agreement with relevant others (but it is easy to imagine uncertainty being produced by agreement with someone with whom we expect to disagree). The predictions of self-categorization theory are also shown in Figure 1.

The views derived from Festinger’s work (basically the 1950 theory with some modification to deal with uncertainty production on the basis of the 1954 theory) and self-categorization theory are contrasted in Figure 1. It can be seen that the formulations predict different interactions so that there is one crucial cell which is different between the two formulations. Self-categorization theory predicts that uncertainty reduction should take place in both agreement cells (again assuming no ceiling effects), whereas Festinger’s work makes the strong prediction that uncertainty reduction should only take place where stimulus information is limited (though to the extent to which the stimulus information is not perfect in the high information condition there may be some uncertainty reduction, but it should be clearly less).

It is worth noting that although the uncertainty production predictions are similar for the two formulations in this context, they are arrived at through different means. Festinger (1954) only ever predicted uncertainty production following disagreement when stimulus information was limited. Self-categorization theory predicts uncertainty production following disagreement (hypothesis 2). However, this can be coun- tervailed by processes of uncertainty reduction which are motivated by disagreement under conditions of high information (hypothesis 3).

The next question is, of course, how should information be manipulated? The problem lies in manipulating information in a balanced way, and this problem emerges due to performance trade-offs involving attention and effort. Put simply, limiting information may make the task harder, but the effect of making the task harder may be to make the subject try harder. That is, greater attention may be deployed resulting in better performance on the task. Simply increasing the exposure time might not increase information because subjects might pay less attention to the stimuli (alternatively if we increase the exposure time too much it would increase information to the point where they could actually count the stimuli in a dot-estimation task like ours).

A partial solution which emerges from the area of decision processes in visual perception (e.g. Vickers et al., 1985) is to contrast E (Experimenter) and S (Subject) paradigms. An E-paradigm is where the subject is limited in the information made available to them by the experimenter. In an S-paradigm the subject decides how


1

- - LOW High

Information

Festinger’s model

1 Q d

I Change in confidence 4 Agreement + Disagreement

LOW High

Information Self-categorization theory

Figure 1. The predictions for uncertainty reduction and production under Festinger’s model and self-categorization theory

much information to view: subjects receive repeated exposure of the stimuli until they are ready to respond (i.e. they have made a decision). In this way, we can guarantee that the subject has more information (unless they choose to view only one exposure of the stimulus in which case they are effectively in the low information condition), or at least as much information as they require. With these two manipulations (information and agreement) we should be able to conduct a competitive test of Festinger’s and Turner’s formulations.

Method

Design

The study had one between-subjects factor (amount of information) with two levels (low and high). There was also one within-subjects factor (feedback) which also

32 C. McGarty et a].

had two levels (agreement and disagreement). Subjects were randomly assigned to the two conditions and the order in which they completed the blocks of the within- subjects factor was counterbalanced (half having agreement first, the other half having disagreement first), thus order was incorporated as another between-subjects factor.

Subjects

The subjects were 63 introductory psychology students at Macquarie University (both male and female subjects were used).

Procedure

The measures and procedure and independent variables were identical to those in Experiment 2 with the exceptions detailed below. The number of dots per stimulus varied from 11 to 91 and the response range 1 to 100 was used.

Information

The amount of information that subjects had was varied by means of the number of exposures that subjects had to the stimulus. Exposure was either strictly limited to one second (an E-paradigm) or the subjects were allowed to see repeated exposures of the stimuli (an S-paradigm, i.e. exposure is limited by the subject up to a maximum of 10 exposures). In the latter case the subjects were given information until they were ready to make their response.

Low information (E-paradigm)The low information condition is essentially the basic task described in the Method section of Experiment 1 . The stimulus was presented for one second after which the subject responded.

High information (S-paradigm)In this version of the experiment the same number of dots was presented repeatedly to the subjects for periods of one second until either the number of displays had reached 10 or the subject clicked the mouse to demonstrate that they were ready to make a response. The subject then responded as described above. Each display pertaining to a given stimulus had the same number of dots but the actual pattern used was randomly assigned for each display (so that subjects could not actually count the dots).

Feedback

This within-subjects factor had two levels: agreement and disagreement. The nature of the feedback was the same as that in Experiments 1 and 2. In the agreement condition, the feedback given was the subject’s own response plus a random number in the range - 5 to 5. In the disagreement condition the feedback score differed from the response by 19 plus a random number in the range 0 to 5. Whether the number was greater or less than the subject’s response was randomly determined for each trial (unless this resulted in a feedback score outside the range 1 to 100, under which circumstances the alternative feedback score was selected). The amount of agreement and disagreement used in Experiment 3 was smaller than that in the previous studies because the scale range was smaller.


Results

Confidence

The central dependent measure was the change in judgemental confidence on each trial. This was calculated as post-feedback confidence minus pre-feedback confidence. On this basis we conducted a 2 X2X2 ANOVA with order (agree then disagree versus disagree than agree) and information as between-subjects factors and feedback as a within-subjects factor. The actual confidence means (as opposed to the change in confidence scores) are shown in Table 3 whereas the change scores are shown in Figure 2.

Table 3. The effects of feedback and information on confidence: Experiment 3


Group Conf. before Conf. after Conf. before Conf. after

Low 60.6 70.2 59.2 51.2 High 58.7 68.2 54.8 53.6

The analysis of variance for the change in confidence revealed a significant interaction (F(1,58) = 4.0, p < 0.05) in that there was an increase in confidence following agreement ( M low information = 9.6, M high information = 9.5, these means did not differ) and a decrease in confidence following disagreement, but the latter occurred in the low information condition ( M = -8.0) but not in the high information condition ( M = - 1.2, comparisons by the Bonferroni method revealed that there was a bigger decrease in confidence in the low information than high information condition, p < 0.01). This pattern is illustrated in Figure 2. Only the high information- disagreement mean did not differ significantly from zero - implying that there was no change in confidence in this cell.

The analysis also revealed two main effects. First of all, there was a highly significant main effect for agreement (F(1,58) = 71.1, p < 0.001) based on an increase in confidence in the agreement condition and a reduction in confidence in the disagreement conditions. There was also an order effect in that subjects who were exposed to agreement followed by disagreement were somewhat more confident than those who were exposed to disagreement and then agreement (F(1,58) = 5.5, p < 0.05). Since this variable did not interact with the other independent variables this does not complicate the interpretation of the results. There was a tendency for there to be an increase in confidence with high information and a decrease with low information (Ms = 9.6 versus -4.8, F(1,58) = 3.9, p < 0.10) but as Figure 2 indicates, the latter was only true in the disagreement condition.

The pattern suggested by these results is that there is an interaction between group agreement and the information given. Given validation of their responses by a group of similar others, subjects were equally likely to become more confident regardless of the amount of information in favour of that response. When confronted with disagreement, however, they were only likely to become uncertain to the extent to which they have little information in favour of the response.


0 -

1 I Change in contidence 4 Agreement

+ Disagreement

-10 J

Low High Information

Figure 2. The effects of feedback and information on the change in judgemental confidence

Post-test measures

The three post-test variables were perceived self-competence at the task, perceived group competence, and whether the group’s responses were seen as similar to the self. These post-test variables did not mediate (as covariates or independent variables) the results for confidence. The repeated measures design makes the post-test results difficult to interpret because subjects experienced both agreement and disagreement. However, of the 57 subjects we had post-test responses for, 36 reported that they thought the group’s responses were similar to their own and 21 reported that they saw the group’s responses as different from their own (missing data occurred when some post-test data were lost from the computer files). These groups differed in the perceived competence of the group, such that people who saw the group as dissimilar also saw the group as less competent ( M (perceived dissimilar responses) = 50.0 versus M(perceived similar responses) = 64.1, t ( 5 5 ) = 3 . 3 , ~ < 0.01). There was no equivalent variation in self-competence.

All of the subjects in the high information condition chose to see an average of more than one exposure of the stimulus per trial. The mean for all subjects in the high information condition was 4.7. It can be concluded therefore that subjects in the high information conditions did have greater information than those in the low information condition (and the manipulation was therefore successful). Prelimi- nary analyses using the subject’s objective accuracy as a covariate revealed no significant contribution for this variable.

Discussion

A comparison of Figures 1 and 2 shows that the support for self-categorization theory is much stronger than the support for Festinger’s model. There are two points which should be borne in mind though when considering the relative strength of support for the two formulations.


First of all, we must consider the possibility of ceiling effects. Uncertainty cannot be reduced unless it exists in the first place. Where there is no prior expressed uncertainty it is quite possible that there would be no uncertainty reduction due to agreement because there was no uncertainty to reduce. The self-categorization theory predictions rest here on the premise that there is some inherent uncertainty in these judgements. Obviously, if someone’s expressed confidence is already at the top of the scale than no amount of consensual validation can increase it further. Table 2 shows that all means are considerably less than 100 implying that our results are not bound by such ceiling effects.

Secondly, from the Festingerian point of view, it might be argued that the differences in the amount of information were not great enough to allow the effects to be shown. In other words, the manipulation may have been too weak. This would have been a reasonable caveat had we not shown variations in uncertainty production on the same factor. It is unreasonable to argue that the information manipulation was strong enough to lead to variations in the uncertainty production but not strong enough to lead to variations in uncertainty reduction (especially given that we have shown both effects in Experiment 2). The results appear to eliminate Festinger’s explanation in the domain in which his (1950) theory was strongest: Uncertainty reduction (remembering that the theory did not deal directly with uncertainty production).

GENERAL DISCUSSION

We have in these three studies evidence of uncertainty reduction through agreement and uncertainty production through disagreement. We have also shown that uncertainty production is mediated by the amount of information subjects have, but that uncertainty reduction is not. These results are general evidence against any formula- tion which does not deal with the social bases of both uncertainty reduction and production, and particular evidence against the view of uncertainty reduction incorporated in the theory of informal social communication (Festinger, 1950). The results support a self-categorization theory account of uncertainty reduction and production (or at least an account which links the social-normative and cognitive bases of uncertainty reduction and production).

The results support the two general hypotheses about uncertainty reduction through agreement and uncertainty production through disagreement and also provide evidence of uncertainty reduction on the basis of attribution of the disagreement to differences between self and others or in differences in the stimulus situation (hypotheses 3a and 3b). The design of the study eliminated uncertainty reduction through mutual social influence (3c).

The designs of our studies also eliminate explanations of the results in terms of normative influence, effect dependence or a concern for being liked. In the first instance, subjects did not have the chance to change their responses after social influence. It was impossible for them to comply with the response of the group to avoid sanctions even if they had wanted to. It is also unreasonable to expect that subjects would have changed their confidence ratings because they feared sanctions from a group of people who were not physically present and who had (purpor-

36 C. McGurty et al.

tedly) responded to the stimuli last year. To the extent that uncertainty was created or reduced by other people we must attribute it to variations in their beliefs about the correctness of their own response and not to a fear of social sanctions.

If anything, social desirability effects could be expected to work against the possibility of us finding variations in confidence. We accept the view (Festinger, 1950, 1954) that it is normatively positive to be confident (i.e. to have accurate opinions). It follows that people can be expected to be relatively unwilling to display low levels of confidence. It is worth nothing that where subjects who experienced disagreement gave low competence ratings to themselves they also rated the group less favourably as well.

The attributional results from these studies are interesting. In Experiments 1 and 2, the fact that people rated both themselves and the group as less competent when exposed to disagreement suggests that they attributed disagreement to the possibility that either the group or themselves (or both) were wrong. They appeared to attribute agreement to the reasonable possibility that both the group and themselves were correct. A similar analysis can be made of Experiment 3. When subjects received agreement confidence increased because agreement was attributed to the possibility that both responses corresponded with the underlying reality. When they experienced disagreement, however, their confidence was not affected by the group when information was high. This may mean that they rejected the group when they had reasonable grounds to do so. In short, these results provide further support for self- categorization theory’s proposition that in the face of disagreement alternative processes of uncertainty reduction can be motivated by the stimulus situation.

The range of stimuli used in these studies supports the generalizability of the current results and suggests avenues for further research. We need to examine the replicability of these findings under a wider range of task difficulty conditions. Fur- thermore, it would be useful to examine uncertainty reduction and production in conjunction with variables which would allow tests of theories of minority influence. We regard the trial-by-trial measurement of confidence, the absence of an opportunity to change one’s response, and the manipulation of information (in terms of E- and S-paradigms) as important methodological features in such investigations. Further research must also be directed to critical tests of the self-categorization perspective on uncertainty. Work on the interrelationship between the social-normative and cognitive aspects of uncertainty reduction (with particular reference to the process of categorization) is currently in progress (see McGarty and Turner, in press). From a self-categorization theory perspective we need (1) to examine directly the mediating role of the attribution of disagreement (similar attributional issues have been a major theoretical concern in minority influence research for some time, see Maass and Clark, 1984), and (2) to investigate the role of attention to the stimulus in the processes of uncertainty reduction. Consideration of these variables will enable us to establish whether disagreement can produce uncertainty under conditions of high information, and if it does whether it is moderated by the alternative (motivated) processes of uncertainty reduction suggested by self-categorization theory.

In conclusion, we feel that these results are strong evidence against Festinger’s (1950, 1954) theorizing on uncertainty reduction. This theorizing is still a dominant perspective in the social influence field (see Turner, 1991). There is, of course, still much in these theories which is insightful, and they represented a major theoretical advance at a time when social psychology was able to profit from such theories.


It is less remarkable that important elements of such crucial theories have been disconfirmed than that there have been so few serious attempts to test them.

ACKNOWLEDGEMENTS

We would like to acknowledge financial assistance from the Australian Research Council for Grant A790301 87 for the ‘Social influences on cognition’ project.

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