The Impact of Celebrity Endorsement and Celebrity Co-branding on Perceived Quality: The Role of Celebrity Application Frequency Within a Brand

Retailers have used celebrity endorsement (CE), an advertising strategy, for several decades to advertise the retailer's brand or their private labels (PL); however, the emergence of celebrity co-branding (CCOB), a branding strategy, in combination with PL is a relatively new trend worldwide. Evidence from practice indicates that the most successful co-branded premium PL are the ones offering a wide range of products. Apart from superior brand management, this trend might be a result of consumers' perceived impact of CCOB increasing with the number of products co-branded by the same brand allies. The existing CE, CCOB, and traditional co-branding literature have not yet addressed the effect of multiple applications of any of these strategies on a range of products within the same brand (i.e., celebrity application frequency). However, applying existing findings on the effect of one endorser recommending many different brands to our research context, we hypothesize a negative impact when a spokesperson endorses multiple products within a brand. We propose that consumers perceive CE and CCOB differently when the number of endorsed or co-branded products increases. Indeed, our experiment reveals an interaction between celebrity application type and celebrity application frequency but no main effects. This finding indicates that when either strategy is applied multiple times within the same brand, product evaluations increase in the case of CCOB and decrease in the case of CE.