Sofia Berto Villas-Boas

Consumer and Market Responses to Mad Cow Disease

We examine how consumers and financial markets in the United States react to two health warnings about mad cow disease: the first discovery of an infected cow in December 2003 and an Oprah Winfrey show on the potentially harmful effects that aired seven years earlier. Using a unique product-level scanner data set of a national grocery chain, we find a pronounced and significant reduction in beef sales following the first discovered infection, which dissipates slowly over the next three months. Cattle futures show a comparable pattern of abnormal price drops to the scanner data. Contracts with longer maturity show smaller drops, suggesting that the market anticipated the impact to be transitory. Cattle futures show abnormal price drops after the Oprah Winfrey show that are more than 50% of the drop following the 2003 discovery of an infected cow.

Got Organic Milk? Consumer Valuations of Milk Labels after the Implementation of the USDA Organic Seal

This paper investigates consumer reactions to changes in information provision regarding organic production. Quantitative analyses focus on the actual implementation of mandatory labeling guidelines under the National Organic Program. The unique nature of the fluid milk market in combination with these regulatory changes allows us to place a value on information sets under different labeling regimes. Hedonic price functions provide an initial reference point for analyses of individual responses. A random utility discrete choice model serves as the primary econometric specification and allows consideration of consumer preference heterogeneity along observable household demographics. Our results indicate that the USDA organic seal increases the probability of purchasing organic milk. An initial hedonic price function approach, as well as simulations within the discrete choice framework, suggests that consumers value the change in labeling regulations with regard to organic production. Our results further suggest that consumers substitute away from milk carrying the rBGH-free label. This may indicate that consumers pay less attention to these labels in the time period investigated compared to results found in studies that use earlier time periods.

Tracking the Libor rate

With an eye to providing a methodology for tracking the dynamic integrity of prices for important market indicators, in this paper we use Benford second digit reference distribution to track the daily London Interbank Offered Rate (Libor) over the period 2005-2008. This reference, known as Benford’s law, is present in many naturally occurring numerical data sets as well as in several financial data sets. We find that in two recent periods Libor rates depart significantly from the expected Benford reference distribution. This raises potential concerns relative to the unbiased nature of the signals coming from the sixteen banks from which the Libor is computed and the usefulness of the Libor as a major economic indicator.

Expert Opinion and the Demand for Experience Goods: An Experimental Approach in the Retail Wine Market

The effect of expert opinion on demand for experience goods is difficult to quantify, as the relationship between purchases and reviews may be driven by product quality. Further, it is unclear whether a review-based demand effect is due to providing quality or existence information. Using a retail field experiment to overcome these obstacles, we find a significant positive average consumer response to expert opinion labels for wine. Demand decreases for low-scoring wines and increases for wines scoring average or higher. Results indicate that expert opinion labels transmit quality information as opposed to solely shelf visibility.

Reformulating Competition?: Gasoline Content Regulation and Wholesale Gasoline Prices

The 1990 Clean Air Act Amendments stipulated gasoline content requirements for metropolitan areas with air pollution levels above predetermined federal thresholds. The legislation led to exogenous changes in the type of gasoline required for sale across U.S. metropolitan areas. This paper uses a panel of detailed wholesale gasoline price data to estimate the effect of gasoline content regulation on wholesale prices and price volatility. We investigate the extent to which the estimated price effects are driven by changes in the number of suppliers versus geographic segmentation resulting from regulation. We find that prices in regulated metropolitan areas increase significantly, relative to a control group, by an average of 3 cents per gallon. The price effect, however, varies by 8 cents per gallon across regulated markets and the heterogeneity across markets is correlated with the degree of geographic isolation generated by the discontinuous regulatory requirements.

Can household consumers save the wild fish? Lessons from a sustainable seafood advisory

Conservation organizations seeking to reduce over-fishing and promote better fishing practices have increasingly turned to market-based mechanisms such as environmental sustainability labels (eco-labels) in order to shift patterns of household consumption. This paper presents an analysis of consumer response to an advisory for sustainable seafood adopted by a regional supermarket in the United States. The advisory consisted of a label in which one of three traffic light colors was placed on each fresh seafood product to inform consumers about its relative environmental sustainability. Green meant “best” choice, yellow meant “proceed with caution,” and red meant “worst choice”. Using a unique product-level panel scanner data set of weekly sales and taking advantage of the random phase-in of the advisory by the retailer, we apply a difference-in-differences identification strategy to estimate the effect of the advisory on overall seafood sales as well as the heterogeneous impact of the advisory by label color and whether the seafood met additional health-related criteria. We find evidence that the advisory led to a statistically significant 15.3% decline in overall seafood sales, a statistically significant 34.9% decline in the sale of yellow labeled seafood, and a statistically significant 41.3% decline in the sale of yellow labeled seafood on a mercury safe list. We find no statistically significant difference in sales of green or red labeled seafood.

Learning, Forgetting, and Sales

Sellers of almost any product or service rarely keep their prices constant through time and frequently offer price discounts or sales. This paper investigates an explanation of sales as a way for uninformed consumers to be willing to experience the product, and learn about its fit, and where informed consumers may forget about (or change) their preferences. We investigate the role of the rate of consumer forgetting on the timing between sales, and of the rate of consumer learning and menu costs on the length of a sale. The rate of consumer forgetting can be linked to the length of purchase cycle and the level of consumer involvement. We show that the discount frequency and the discount depth are increasing in the rate of consumer forgetting, and that the discount frequency is increasing in the learning rate. The duration of a sale is increasing in the rate of consumer forgetting and the rate of consumer learning.

Food Store Choices of Poor Households: A Discrete Choice Analysis of the National Household Food Acquisition and Purchase Survey (FoodAPS)

Policymakers are pursing initiatives to increase food access for low-income households. However, due in part to previous data deficiencies, there is still little evidence supporting the assumption that improved food store access will alter dietary habits, especially for the poorest of U.S. households. This article uses the new National Household Food Acquisition and Purchase Survey (FoodAPS) to estimate consumer food outlet choices as a function of outlet type and household attributes in a multinomial mixed logit model. In particular, we allow for the composition of the local retail food environment to play a role in explaining household store choice decisions and food acquisition patterns. We find that households are willing to pay more per week in distance traveled to shop at superstores, supermarkets, and fast food outlets than at farmers markets and smaller grocery stores, and that willingness to pay is heterogeneous across income group, Supplemental Nutrition Assistance Program participation, and other household and food environment characteristics. Our results imply that policymakers should consider incentivizing the building of certain outlet types over others, and that Healthy Food Financing Initiatives should be designed to fit the sociodemographic composition of each identified low-income, low-access area in question.

An Introduction to Auctions

These lecture notes provide an introduction to auctions. They can be covered in two or three lectures. This material is appropriate for the last part of a first-year graduate industrial organization course or as an introduction to an auctions course.

Retail Mergers and Food Prices: Evidence from France

This paper analyzes the impact of a merger in the French supermarket industry on food prices. Using consumer panel data, we compare the changes in prices for merging and rival firms in affected and comparison markets. We use a novel definition of affected markets when some firms have a local pricing strategy and others a more centralized pricing strategy. We find that prices increase significantly following the merger, and that the merging firms lose market shares. For the rivals, the price increases are larger in local markets, in which concentration increased and differentiation changed after the merger.