Communication accuracy as a function of information about the communicator

The accuracy with which Ss could identify the national governments referred to by a set of semantic-differential profiles was found to be significantly related to whether they were given true, false, or unspecific information concerning the source of the profiles. Contrary to hypothesis, attitude similarity between the Ss who constructed the profiles and those who interpreted them failed to enhance communication accuracy.     

Initial attitude,source credibility,and involvement as factors in persuasion

Source credibility was manipulated in factorial combination with the measured variables of initial attitude, issue involvement, and sex, using Japanese university students as subjects. A significant credibility × initial attitude interaction replicated previous findings and was attributed to disparagement of the less credible of two communicators by subjects whose initial attitudes were extremely discrepant from the position advocated. The significant involvement × initial attitude interaction reflected the greater resistance of highly involved subjects to persuasion under extreme rather than under moderate communicator-recipient discrepancy.     

The credibility of a source influences the rate of unconscious plagiarism

Three experiments were conducted to investigate the relationship between the credibility of information and later unconscious plagiarism of that information. In each experiment, ideas concerning ways to reduce traffic accidents were presented from a more credible source (traffic planners) and a less credible source (college freshmen). After a distractor task, participants were asked to generate novel ways to reduce traffic accidents. In Experiments 1 and 2, unconscious plagiarism of ideas presented from the more credible source was greater than from the less credible source. In neither experiment was explicit memory for ideas from each source different in tests of source monitoring or free recall. However, the difference in unconscious plagiarism was eliminated in Experiment 3 by having participants generate the implications of ideas at study. The results are discussed in terms of the explicit factors that affect the incidence of unconscious plagiarism.     

When credibility attacks: The reverse impact of source credibility on persuasion

Recent research on the self-validation hypothesis suggests that source credibility identified after message processing can influence the confidence people have in their own thoughts generated in response to persuasive messages (Briñol, Petty, & Tormala, 2004). The present research explored the implications of this effect for the possibility that high credibility sources can be associated with more or less persuasion than low credibility sources. In two experiments, it is demonstrated that when people generate primarily positive thoughts in response to a message (e.g., because the message contains strong arguments) and then learn of the source, high source credibility leads to more favorable attitudes than does low source credibility. When people have primarily negative thoughts in response to a message (e.g., because it contains weak arguments), however, this effect is reversed—that is, high source credibility leads to less favorable attitudes than does low source credibility.     

Readers' reliance on source credibility in the service of comprehension

The current project examined the impact of knowledge about the credibility of sources on readers' processing of texts. Participants read texts in which information about characters was provided by either a credible or a noncredible source; this information suggested that the character potentially possessed a particular trait. A subsequent text episode offered the opportunity for participants to apply any inferred trait to their understanding of unfolding story events. In Experiment 1, participants' moment-by-moment reading times indicated strong expectations for characters to behave in trait-consistent ways, with little effect of credibility on those expectations. Experiments 2 and 3 provided participants with additional encouragement to attend to credibility during reading, but these experiments also revealed little influence of credibility. In Experiment 4, in addition to being given added encouragement, participants were explicitly asked to evaluate the likelihood of future text events; under these conditions, expectations for story outcomes were influenced by the credibility of information sources. This influence was mediated by the degree to which participants self-reported relying on credibility during the task. These findings have implications for contemporary accounts of text comprehension, persuasion, and individual differences in credibility assessment. (PsycINFO Database Record (c) 2010 APA, all rights reserved).     

Information relevance,content and source credibility in the revision of opinions

In the first of two experiments participants assessed either (1) the probability of success or (2) the acceptability of hypothetical job candidates. These judgments were made on the basis of information about particular traits or abilities possessed by the candidate. The traits themselves varied in relevance to the job and the sources of information differed in credibility. Results showed that use of the information changed in that it had reduced influence (was “discounted”) on the judgment when its relevance decreased and when its sources' credibility decreased. Discounting was a multiplicative rather than a subtractive process and the same process apparently accounted for both the acceptability judgments and the probability assessments, which were very similar. In the second experiment, participants received three pieces of information about the potential negative effects of constructing nuclear power plants on a number of potential sites. For each site, participants revised their judgments about the favorableness of the site after each of the three pieces of negative information. Again, multiplicative discounting was obtained as a function of the credibility of the information sources and a form of “conservatism” was obtained; regardless of the source and the content of the message, the amount of revision decreased from the first to the second to the third revision.     

Reading is believing: the truth effect and source credibility

Five experiments explored how source reliability influences people’s tendency to rate statements as more credible when they were encountered earlier (the truth effect). Undergraduates read statements from one reliable source and one unreliable source. Statements read multiple times were perceived as more valid and were more often correctly identified on a general knowledge test than statements read once or not at all. This occurred at varying retention intervals whether the statements originated from a reliable or unreliable source, when people had little memory for the statements themselves or their source, and when the discrediting information about the sources came either before or after reading the facts. While repetition aided recognition and source accuracy, both were unaffected by the reliability of the source. Consistent with the source monitoring framework, familiarity may create an illusion of truth for statements when people lack source-specifying cues, especially cues regarding the reliability of the source.     

Correcting erroneous inferences in memory: The role of source credibility

People often continue to rely on erroneous information about people and events, even in the face of subsequent counter information. The current study examined whether this information could be effectively corrected by a credible source. We examined two aspects of credibility: trustworthiness and expertise. Experiment 1 showed that receiving a correction from a source high in trustworthiness and expertise reduced participants’ use of original information when making inferences. Experiment 2 showed that source expertise alone was not sufficient to reduce participants’ reliance on the original information. The results from Experiment 3 showed that source trustworthiness alone significantly decreased participants’ use of the original information when making inferences. The results suggest that people may be able to reduce their use of original information if they receive a correction from a person who is deemed to be highly trustworthy. These findings have implications for decision making in politics and other applied areas.     

Calibration trumps confidence as a basis for witness credibility

Confident witnesses are deemed more credible than unconfident ones, and accurate witnesses are deemed more credible than inaccurate ones. But are those effects independent? Two experiments show that errors in testimony damage the overall credibility of witnesses who were confident about the erroneous testimony more than that of witnesses who were not confident about it. Furthermore, after making an error, less confident witnesses may appear more credible than more confident ones. Our interpretation of these results is that people make inferences about source calibration when evaluating testimony and other social communication.     

The role of social categorization and perceived source credibility in minority influence

This study was conducted in order to compare the influence of ingroup and outgroup minorities and to assess the role of perceived source credibility in minority influence. The subjects were exposed to the simultaneous majority/minority influence paradigm. Ingroup minorities were more influential than outgroup minorities. Subjects moved toward the minority position in private and toward the majority position in public when the minority was represented by members of the ingroup. On private responses subjects were not affected by outgroup minorities who argued for abortion, and they became more positive toward abortion when outgroup minorities opposed abortion. Final &, ingroup minorities were perceived as more credible than outgroup minorities and greater credibility of minority source was associated with greater attitude change toward the minority position. The superior influence of ingroup minorities held when controlling for source credibility. Overall, the results were highly supportive of social identity theory.