Eco-Labels for Credence Attributes: The Case of Shade-Grown Coffee

Using the case of shade-grown coffee, this paper examines the market impacts of eco-labels for credence attributes. First, the Mattoo and Singh (1994) test is conducted for the case of shade-grown coffee to investigate the market impacts of a shade label. This analysis in Section II shows that a shade label could pass the test, but the market impacts are likely to be minor. Section II also shows how to use estimates of supply, potential demand, and price elasticities of demand and supply to predict eco-label premiums in the post-label equilibrium. And second, given the importance of consumer demands for eco-label impacts, and since the theoretical foundations of demand for eco-labeled items are not well developed in the literature, Section III takes a closer look at the microeconomics of labels and consumer demand. A nested constant-elasticity-of-substitution preference structure is used to derive theoretically consistent Marshallian demands for shade and non-shade coffee. A numerical simulation shows how relative prices and consumer preferences for the credence attribute and variety are both important factors in demand creation of labeled items.