The Legacy of Gurus: The Impact of Armin Diel and Joel Payne on Winery Ratings in Germany

Abstract

Changes in winery ratings in leading wine guides, that is, improvements as well as deteriorations, are typically attributed to corresponding changes in the quality of the wines produced by the respective winery. What remains unexplored in this context is changes in editorship and/or changes in the composition of the wine tasting teams working for the respective guide. Using data from two particularly prestigious German wine guides (Gault Millau and Vinum), this paper shows that these latter changes have a rather small, yet statistically significant impact on changes in winery ratings. Thus, consumers are well-advised to consider these changes before making their purchasing decision. (JEL Classifications: L21, M30, Q13)

Ratings meet prices: The dynamic relationship of quality signals

“…Schamel (2002) analyzed the existing link between wine prices and the reputation of a wine producer. Frick (2020) demonstrated how expert opinions affect the reputation of wineries and how changes in the editorship of renowned wine guides could alter the ratings of wineries. Besides this market-influencing potential and the possible impact on wine prices and market performance of the wineries, current studies have also shed light on the composition of expert knowledge (e.g., Ashton, 2017) and the consistency of (star) expert ratings across various wine products and rating platforms (e.g., Marks, 2015; Ashton, 2012, 2013; Oczkowski, 2017).…”

“…This provides insight into the long-term motivation of winemakers to either hold the quality of the product at a constant level or even improve it (for better or worse). Second, we are interested in looking at reviewer attitudes to gain more insight into the consistency of professional evaluations (e.g., Frick, 2020). Here, we reflect on the reviewers’ behavior, in that previous reviews may impact their current reviews.…”