世界経済・社会統計 = World development indicators

Co-Planar Stereotaxic Atlas of the Human Brain—3-Dimensional Proportional System: An Approach to Cerebral Imaging, J. Talairach, P. Tournoux. Georg Thieme Verlag, New York (1988), 122 pp., 130 figs. DM 268

计量经济分析 = Econometric analysis

In 1974 an article appeared in Science magazine with the dry-sounding title “Judgment Under Uncertainty: Heuristics and Biases” by a pair of psychologists who were not well known outside their discipline of decision theory. In it Amos Tversky and Daniel Kahneman introduced the world to Prospect Theory, which mapped out how humans actually behave when faced with decisions about gains and losses, in contrast to how economists assumed that people behave. Prospect Theory turned Economics on its head by demonstrating through a series of ingenious experiments that people are much more concerned with losses than they are with gains, and that framing a choice from one perspective or the other will result in decisions that are exactly the opposite of each other, even if the outcomes are monetarily the same. Prospect Theory led cognitive psychology in a new direction that began to uncover other human biases in thinking that are probably not learned but are part of our brain’s wiring.

Thinking fast and slow.

The author systematically examines one of the important issues of information — establishing the market price. He introduces the concept of «search» — where a buyer wanting to get a better price, is forced to question sellers. The article deals with various aspects of finding the necessary information.

Economics of Information

The net impact of pest-resistant GM crops on the welfare of both producers and consumers in developing countries is currently unknown and subject to speculation. This study uses choice-based conjoint protocol to estimate the net impact of pest-resistant Genetically Modified (GM) cowpea on net social welfare in Benin given price and income risks. Results imply that Bt cowpea will increase expected net social welfare by about $US 50 million per year in Benin given no inefficiencies in the seed sector. If inefficiencies in the seed sector are such that cowpea growers can access Bt cowpea seeds only 50% of the time, net benefits from Bt cowpea drop to about $US 11 million per year.

Ex Ante Economic Impact of Genetically Modified (GM) Cowpea in Benin

Little research has been conducted on evaluating out-of-sample forecasts of limited dependent variables. This study describes the large and small sample properties of two forecast evaluation techniques for limited dependent variables: receiver-operator curves and out-of-sample-log-likelihood functions. The methods are shown to provide identical model rankings in large samples and similar rankings in small samples. The likelihood function method is slightly better at detecting forecast accuracy in small samples, while receiver-operator curves are better at comparing forecasts across different data. By improving forecasts of fed-cattle quality grades, the forecast evaluation methods are shown to increase cattle marketing revenues by $2.59/head.

Forecasting Limited Dependent Variables: Better Statistics For Better Steaks

The inability and undesirability of local croplands to meet food demand

This study estimates wholesale demand for pork, chicken, and quality differentiated beef. We estimate meat retailer own- and cross-price demand elasticities for USDA Choice and Select boxed beef. Results indicate that meat retailers have more elastic demand for lower quality graded beef. Retail beef price has a strong positive relationship with Choice and Select boxed beef demand, and a strong negative relationship with wholesale pork and chicken demand. Seasonal analysis reveals demand for both beef quality grades becomes highly price inelastic during the summer months. The two beef quality grades are substitutes during the winter; however, Select beef is not a substitute for Choice beef in the spring and summer.

Quality Graded Boxed Beef and Effects of Seasonality

In an effort to help Americans make healthier food choices, U.S. lawmakers recently mandated certain restaurants to add calorie labels to their menus. In this study, we implement the same numeric calorie labels in two different full service restaurants using two different experimental designs. Ultimately, both field experiments lead us to the same conclusion: the numeric calorie label (as currently proposed by the FDA) had little effect on total caloric intake. Our results do reveal, however, that the effectiveness of the numeric label could be enhanced with the addition of a traffic light symbol identifying low-, medium-, and high-calorie items.

Jayson L. Lusk

Papers

Ex Ante Economic Impact of Genetically Modified (GM) Cowpea in Benin

Forecasting Limited Dependent Variables: Better Statistics For Better Steaks

The inability and undesirability of local croplands to meet food demand

Quality Graded Boxed Beef and Effects of Seasonality

Effect of Menu Labeling on Caloric Intake and Restaurant Revenue in Full-Service Restaurants