This dissertation explores the socio-cognitive system of collective influences on consumers’ evaluation and decision processes, which have not been discussed fully in consumer literature, by examining how people resolve a conflict between group orientation and trait regulatory focus. It is proposed that, depending on the interaction between group commitment and collective efficacy, consumers implement one of three conflict resolution processes (i.e., depersonalization, compliance, and self-preservation) to determine the outcome of their regulatory shift. The impact of these three conflict resolution processes on regulatory shift and following message evaluations are tested with a series of six experiments. The results of these studies showed that people shift their regulatory orientation from trait regulatory focus to group orientation if the group identity is strong enough (experiment 1 and 2), the impact of group orientation on message evaluation is stronger when group members have higher group commitment (i.e., depersonalization; experiment 3 and 4) or experience higher collective efficacy (i.e., compliance; experiment 5), and people experience regulatory non-fit when they follow compliance process and generated less favorable message evaluations than when they follow depersonalization process (experiment 6). These findings highlight the importance of understanding group influence on a consumer’s mindset that consequently affects his/her various psychological processes and consumption behaviors.

This study establishes a link between research on organizational source credibility and the effects of public information campaigns. Research has established that source credibility is one factor audiences evaluate when responding to messages and that credible information sources enhance message acceptance, while untrustworthy sources can interfere with desired message effects. Although source credibility studies have typically focused on the person delivering a message, recent studies indicate that audience perceptions of the organization sponsoring a message has a direct effect on message acceptance as well. Additionally, a few studies indicate that non-profit sources of health information are viewed as more credible, while such messages presented by for-profit organizations are less effective. This study uses an experimental procedure to investigate the relationship between organizational status, source credibility, and two possible effects of public service messages, information seeking and behavioral intent. Based on previous findings, the study hypothesized that the non-profit source would berated as more credible and that as the audiences' perception of source credibility increases so would their willingness to seek additional information or perform the advocated behaviors. Findings indicate, however, that organizational status does not have a significant effect on perceptions of source credibility. Nor does it significantly influence message evaluation, information seeking, or behavioral intent. As predicted, there was a positive correlation between source credibility, message credibility, problem recognition, personal relevance, information seeking, and behavioral intent. The results also indicate that information seeking positively predicts behavioral intent.