Giffen Behavior: Theory and Evidence

This paper provides the first real-world evidence of Giffen behavior, i.e., upward sloping demand. Subsidizing the prices of dietary staples for extremely poor households in two provinces of China, we find strong evidence of Giffen behavior for rice in Hunan, and weaker evidence for wheat in Gansu. The data provide new insight into the consumption behavior of the poor, who act as though maximizing utility subject to subsistence concerns, with both demand and calorie elasticities depending significantly, and non-linearly, on the severity of their poverty. Understanding this heterogeneity is important for the effective design of welfare programs for the poor.

An American BSE Crisis: Has it affected the Value of Traceability and Country-of-Origin Certifications for US and Canadian Beef?

With a BSE incident in the United States (US) in December of 2003, questions arose about the effect of the incident on consumers in the US. The purpose of this paper is to determine if traceability systems for beef can help preserve consumer demand following the discovery of BSE. Auctions were conducted approximately 3 weeks before and after the December 2003 BSE incident in the U.S It was found that overall there was no effect on the size of the bribes needed by the BSE incidence. However, for some groups there were important changes. The results indicate that information about traceability and country of origin is valuable to consumers. They also suggest that greater uncertainty about certifications and assurances for beef existed among the participants after December 23rd than before December 23rd.BSE, Traceability, Country-of-origin, Beef market, Auctions, Food Consumption/Nutrition/Food Safety, Livestock Production/Industries,

Economic Opportunities and Gender Differences in Human Capital: Experimental Evidence for India

Gender differences in health and education are a concern for a number of developing countries. While standard theory predicts human capital should respond to market returns, social norms (e.g., disapproval of women working outside the home) may weaken or even sever this link for girls. Though many studies have examined the link between women's wages or labor force participation and investment in girls, two significant problems are the possibility of omitted variables bias and reverse causality, and difficulty in identifying which of several mechanisms (returns, bargaining power, income, etc.) link the two. To overcome these problems, we provided three years of recruiting services to help young women in randomly selected Indian villages get jobs in the business process outsourcing industry. Girls in treatment villages were more likely to be in school and had greater measured BMI. We argue that the design of the experiment (providing opportunities almost exclusively for young, unmarried women rather than current mothers) allows us to rule out that mechanisms other than increases in the returns explain our results.

An analytically linearized helicopter model with improved modeling accuracy

An analytically linearized model for helicopter flight response including rotor blade dynamics and dynamic inflow, that was recently developed, was studied with the objective of increasing the understanding, the ease of use, and the accuracy of the model. The mathematical model is described along with a description of the UH-60A Black Hawk helicopter and flight test used to validate the model. To aid in utilization of the model for sensitivity analysis, a new, faster, and more efficient implementation of the model was developed. It is shown that several errors in the mathematical modeling of the system caused a reduction in accuracy. These errors in rotor force resolution, trim force and moment calculation, and rotor inertia terms were corrected along with improvements to the programming style and documentation. Use of a trim input file to drive the model is examined. Trim file errors in blade twist, control input phase angle, coning and lag angles, main and tail rotor pitch, and uniform induced velocity, were corrected. Finally, through direct comparison of the original and corrected model responses to flight test data, the effect of the corrections on overall model output is shown

Do Consumer Price Subsidies Really Improve Nutrition?

Many developing countries use food-price subsidies or price controls to improve the nutrition of the poor. However, subsidizing goods on which households spend a high proportion of their budget can create large wealth effects. Consumers may then substitute towards foods with higher non-nutritional attributes (e.g., taste), but lower nutritional content per unit of currency, weakening or perhaps even reversing the intended impact of the subsidy. We analyze data from a randomized program of large price subsidies for poor households in two provinces of China and find no evidence that the subsidies improved nutrition. In fact, it may have had a negative impact for some households.