Synergy in multi-channel online advertising

In the past decade, the internet has become a major medium for advertisers. With the growing variety of advertising media and online advertising channels, measuring advertising effectiveness and optirnally managing the advertising rnix has become increasingly complex, In particular, synergy effects have become more relevant due to the growing importance of multimedia and multi-channel advertising. However, academic research has so far failed to measure the effectiveness of the various channels in onIine advertising in a comprehensive model, The present study addresses these issues and introduces a methodology for assessing the effectiveness of advertising in a multi-channel environment based on readily available behavioral data. Hypotheses are developed based on the Elaboration Likelihood Model. To empirically test the hypothesized research model, internal secondary data from a leading platform for trading used and new books online are acquired. These data span aperiod of 365 days, encompassing a total of over 2.8 million purchases made by approximately 1.1 million consumers, and are extracted directly from the databases ofthe company, The analysis shows that advertising exposures affect purchases, exposures within the same advertising channel, and exposures in other advertising channels. Causal interrelations between advertising channels are found to play a key role in the effectiveness ofindividual channels, while synergy from interaction is not found.