Three essays on spillover effects of product certifications on non-certified bystander products
Creators: name: Wulf, Linda
Publisher: name: Technische Universität Dortmund
Year: 2018
Subjects: subject: Spillover Effekte
subject: Produktzertifizierungen
subject: Gütesiegel
subject: Bystander Effekte
subject: 330
subject: Spill-over-Effekt
subject: Gütezeichen

description: At a time when consumers are increasingly conscious of sustainable- and quality-oriented consumption, many companies respond to these new demands by launching certified options in addition to their standard assortment. Consequently, product lines consist of both certified and uncertified alternatives. While considerable research has examined the effects of such certifications, the focus has been exclusively on the labeled products, neglecting portfolio-related consequences for non-certified alternatives (‘bystander’ products). The objective of this research was to close this gap by conceptually and empirically investigating the occurrence as well as determinants of such bystander effects. Therefore, a holistic framework of spillover effects was developed based on a structured review of underlying theories, and synthesis of disparate literature streams focused on spillover (i.e., brand extension, co-branding, ingredient branding, quality seals, endorsement, sponsorship, and country of origin effects). This two-step model provided the theoretical framework for the subsequent investigation of bystander effects in the context of sustainability labeling. In a field study, it was demonstrated how partial certification can have a detrimental effect on choice shares of the own bystander products, whereas competing products remain unaffected, resulting in strong intra-brand cannibalization effects. It was further revealed that these observed negative effects were caused by altered perceptions of product attributes which consumers associate with a specific certification (e.g., quality, fairness). In line with the previously presented mechanisms necessary for the occurrence of bystander effects, this detrimental effect only occurred for bystander products of the same brand due to its stronger mental association with the certified target product. To understand these changes in perceptions and underlying psychological mechanisms in more detail, a mixed-methods approach offered new insight into how a partial certification strategy affects consumer evaluations of own bystander products in a three-fold manner: Changes in the reference framework used to assess bystander products impair perceptions of the product’s attributes, as it appears inferior compared to the certified product (reference effect). Simultaneously, enhanced perceptions of the target product spill over to the bystander because of their shared affiliation (spillover effect). Finally, consumers perceive a brand’s meaning as inconsistent if it certifies only select products, which raises skepticism of the brand’s overall intentions (inconsistency effect). Finally, a series of online experiments and a field study were conducted to examine what factors determine the strength and direction of bystander effects. Particularly, the degree of a brand’s perceived control over certification of its products, brand reputation, fit between certification and brand, pricing, as well as shelf placement were identified to be of relevance. Overall, the presented findings substantially contribute to existing research in the context of product certifications. The more expansive perspective allows for the assessment of a certification’s overall benefit with regards to the brand portfolio in its entirety, which offers highly relevant practical implications.