Knape, Dominic AlexanderDominic AlexanderKnape2023-04-132023-04-132021https://www.alexandria.unisg.ch/handle/20.500.14171/111116Online platforms play an important role in digital commerce by connecting buyers and sellers. However, the growing popularity of digital marketplaces also leads to conflicts: on the one hand, through increasingly intense competition between sellers, and, on the other hand, through conflicts of interest between sellers and platform owners. Dynamic and uncertain platform markets pose various challenges for sellers and lead to uncertain sales performance. This dissertation applies different theories and methods to show how sellers can respond to these dynamic markets to increase product success. The first article in this dissertation identifies three challenging platform dynamics that sellers commonly face and that complicate the predictability of product success. We argue that online product legitimacy can counteract these dynamics and serve as a mechanism for steering product success in uncertain environments. The second article aims to increase transparency regarding Amazon’s market position. Amazon Marketplace is one of the largest and most revenue-generating e-commerce platforms worldwide. However, it is generally unknown as to how this revenue is distributed among different product categories. In order for merchants to better understand and use Amazon’s market position, we have developed the Amazon Market Dominance Index (ADMI), which shows Amazon’s market power in each product category. Based on the results of the first two studies, we developed an intervention tool in the form of an online application. The Amazon Product Listing Optimization (APLO) tool helps companies to optimize the quality of their product pages on Amazon in order to achieve a higher conversion rate and, thus, product success. The last study evaluates the effectiveness of the APLO tool in supporting the implementation of product-page optimizations. We also investigate the impact of these product-page optimizations on sales performance at Amazon. The results of this dissertation show how sellers can reduce uncertainties and better establish themselves in digital marketplaces. The results and application projects allow for more substantiated, evidence-based decisions for Marketplace sellers and thus increase success in this dynamic environment.enElectronic CommerceMarktanteilMarktmachtWettbewerbsverhaltenAmazon.com Inc.EDIS-5054doctoral thesis