Abstract: Most new products were introduced to the market by way of brand extension. It seems important for researchers and practitioners to understand how and why advertising for brand extension works. However, past advertising research mostly used fictitious brands as experimental materials. Because little attention had been given to advertising for brand extensions, the process by which advertising may impact attitude change of extended brands was largely ignored, and the influences of brand familiarity were seldom considered in the traditional persuasive hierarchy models. Furthermore, some research studies indicated that advertising for familiar brands may not work in the same way as advertising for unfamiliar brands, suggesting that research on familiar brands’ advertising has significant theoretical and practical meaning. The purpose of the present study was to modify a dual mediation model (DMM) and to use the model to examine the effects of advertising for brand extensions.
DMM, which derives from cognitive response theories, is a kind of persuasive hierarchy causal model. In the past 20 years, researchers using DMM have found the model to “best” fit the data in several experiments. However, most of these examinations used unfamiliar brands only. In the present study, we extended DMM into familiar brands and employed prior brand attitudes as exogenous variables.
Five hundred sixty-four students at three Chinese universities participated in three studies. The experimental brand and advertising were selected according to whether or not brand extension was executed. In the main experiment, subjects were first asked to evaluate the experimental brand. Subjects were then exposed to the advertising stimuli and were finally asked to complete the following measures: attitudes toward advertising (Aad), advertising cognitive responses (Cad), brand cognitive responses (Cb), post-exposure brand attitudes (Ab) and purchase intention (Pi). In order to examine the internal validity of this pretest-posttest design, we conducted another no treatment pretest-posttest experiment. A replication study about another established brand was also carried out to examine the external validity of the results. This cross-validation procedures supported the conclusion that the extended model is invariant across different brands.
The experiments yielded three sets of findings. First, prior brand attitudes (PAb), which integrated the cumulated marketing efforts, had a significant impact on Cad, Cb and Ab. The implication is that, when researchers investigate the psychological constructs that occur as a result of familiar brands’ advertising exposure, PAb should not be ignored for it contributes to the formation of Aad and Ab. The results also showed that the effectiveness of extended brands’ advertising relied on whether or not consumers favored the brand. Second, the formation of Aad was a direct function of Cad and was an indirect function of PAb. This finding indicates that favorable prior attitude brings about strong attention to processes that help to form Aad and increases advertising effectiveness. Third, similar to DMM, Aad had a direct as well as an indirect effect on Ab through the mediating influence of Cb. Our findings were different from previous findings in that the direct effect of Aad on Ab was less than that yielded by unfamiliar brands. Our findings were also different from those of previous research in other ways that carry theoretical and practical implications. These findings are potentially relevant for brand managers and advertising managers who are concerned with the impact of advertising. The findings are also of particular interest to marketing researchers who study the psychological constructs of advertising as well as to those who wish to explore the marketing implications of brand extensions

Key words: prior brand attitudes, dual mediation model, brand extension