Spillover Effects of Certified Products on Non-Certified Products of the Same Brand - An Empirical Analysis of Effect Size and Direction

在德国，超过1000种不同质量的印章装饰产品、服务和各种在线产品。例如，仅考虑食品行业，大约有300种不同的证书肯定了不同产品的质量（Wagner 2000， Ökotest Kompakt 2010）。先前的研究表明，这种质量信号特别适合减少消费者对认证产品质量的不确定性（Gierl and Stich 1999, Hogreve and Wittko 2006, Krischik 1998, Schweiger et al. 1998, Jahn et al. 2005）。然而，深入了解质量印章对非认证产品的影响是罕见的。因此，拟议的项目集中于从更全球化的角度（即分类和品牌层面）分析质量密封件的影响。为了检验分类部分认证的总体效果，将质量印章对认证产品的既定积极影响与对同一品牌非认证产品的潜在非预期溢出效应进行对比。结果提供了关于公司认证工作的建议，表明他们是否应该认证完整的产品线，或者为了成本效率，可以将他们的认证活动限制在部分分类。因此，提出的研究思路是基于这样的假设，即认证产品的引入也会改变对同一品牌非认证产品的看法。为了深入研究质量密封的总体影响，确定有影响的情境、产品相关和个人因素成为拟议研究活动的中心考虑因素。在第一步中，将通过实验研究的方式调查由于品种的部分认证而导致的对同一品牌的认证和非认证产品的看法的预期变化。随后，将使用定性研究设计确定能够影响部分分类认证非预期效果强度的调节因子。我将通过一系列的实验室和现场实验来测试每个确定的调节因子的相关性。最后，实证结果允许在商业实践中更有效地使用部分分类认证的建议有目的的推导。

Far more than 1,000 different quality seals adorn products, services, and diverse online offerings in Germany. For instance, considering solely the food industry, about 300 different certificates affirm the quality of diverse products (Wagner 2000, Ökotest Kompakt 2010). Previous research has shown that such quality signals are particularly suitable for reducing consumers' uncertainty regarding the quality of certified products (Gierl and Stich 1999, Hogreve and Wittko 2006, Krischik 1998, Schweiger et al. 1998, Jahn et al. 2005). However, insights into the effects of quality seals on non-certified products are rare. Therefore, the proposed project is centered toward an analysis of the effects of quality seals from a more global perspective (i.e., assortment and brand level). In order to examine the total effects of partial certifications of assortments, the established positive effects of quality seals on certified products will be contrasted with potential non-intended spillover effects on non-certified products of the same brand. The results provide recommendations regarding companies' certification efforts by indicating whether they should certify complete product lines or can - for the sake of cost efficiency - limit their certification activities to partial assortments. Hence, the proposed research idea is based on the assumption that the introduction of a certified product changes perceptions of non-certified products of the same brand as well. To profoundly investigate the total effects of quality seals, the identification of influential situational, product related, and personal factors becomes central consideration of the proposed research activities. In a first step, the expected changes in perceptions of certified and non-certified products of the same brand resulting from partial certification of assortments will be investigated by means of an experimental study. Subsequently, moderators which are in a position to influence the intensity of the non-intended effects of partial assortment certification will be identified using a qualitative research design. The relevance of each of the identified moderators will be tested my means of a series of lab and field experiments. Finally, the empirical results allow a purposeful deduction of recommendations for a more efficient usage of partial assortment certifications in business practices.