On the determination of the own and competitive effects of different platforms and content on market shares

Although the attention of academic literature about the relationship between social media and brand sales has grown, literature is still lacking analyses on competitive effects amongst brands. Additionally, effects of firm-generated content (FGC) is often generalized to the volume of posts, which combines the effects of different types of content and use of different platforms. We adopte a differential effects Market Share Attraction (MSA) model to capture different effects across brands allowing also for different effects across two social media platforms. We use a unique dataset covering 4 yoghurt brands in the Italian market spanning over 3 years, for which we focus on the social media posts of the brands (i.e., FGC) on both Twitter and Facebook, while controlling for the engagement (i.e., user-generated content derived from FGC) these posts create, as well as for traditional marketing-mix variables. We extend this analysis by looking at differences in effectiveness based on the type of content of the post (Informational, Emotional, and Activating), and consider whether effectiveness changed over time by employing a Dynamic Linear Model version of the MSA. Our preliminary findings indicate that different brands use different strategies over time and that the content of the message might influence the effectiveness in terms of market shares.