THE ROBUSTNESS OF SINGLE INDEX MODELS IN CROP MARKETS: A MULTIPLE INDEX MODEL TEST: COMMENT

Crop Production/Industries, Marketing,

Of Junk Food and Junk Science

The popular press has triumphantly announced that the cause of the obesity epidemic is “junk food.†After a moment’s reflection, however, it seems likely that the true causal structure of the obesity epidemic can be neither single-equation nor univariate. Therefore, while the hypothesis that “junk food†is the cause of obesity has little a priori plausibility, these articles in the popular press present a testable hypothesis that, in spite of some measurement impossibilities, is tested here. While one can always argue about p values etc., it is safe to say that the results show no evidence to indicate support for a causal link. The second section of the paper explains this result and suggests a rudimentary structural model of obesity that begins to address the issues of specification error, simultaneity, etc., that plague much of the obesity research. This model shows that because of the dynamic nature of weight status, there is no necessary reason to expect to find a statistical relation between a person’s observed weight and the amount he or she is currently eating or exercising. Therefore, studies which regress weight, obesity, or the probability of obesity on eating and exercise patterns have serious specification error. Further development of structural econometric models of obesity may lead to consistent estimates of the partial effects of exogenous variables on obesity levels. We conclude with a discussion of the implications for policy development and industry.obesity, junk food, Granger-causality, Research Methods/ Statistical Methods, Teaching/Communication/Extension/Profession, Q10, Q16,

BORROWING BEHAVIOR OF THE PROPRIETARY FIRM: DO SOME RISK-AVERSE EXPECTED UTILITY MAXIMIZERS PLUNGE?

When a proprietor's liability is limited, borrowing behavior for an expected utility maximizer may vary widely. Proprietors with little to lose may rationally choose very large debt levels while others may choose to finance with 100% equity. This article presents a theory to explain these widely observed variations in behavior.Financial Economics,

The Economic Aftermath of the 1960s Riots: Evidence from Property Values

In the 1960s numerous cities in the United States experienced violent, race-related civil disturbances. Although social scientists have long studied the causes of the riots, the consequences have received much less attention. This paper examines census data from 1950 to 1980 to measure the riots' impact on the value of central-city residential property, and especially on black-owned property. Both ordinary least squares and two-stage least squares estimates indicate that the riots depressed the median value of black-owned property between 1960 and 1970, with little or no rebound in the 1970s. Analysis of household-level data suggests that the racial gap in the value of property widened in riot-afflicted cities during the 1970s.

Heart Rate Response to Sound and Light

Heart rate response to varying sound and light intensitie

Race and Home Ownership from the End of the Civil War to the Present

We present new estimates of home ownership for black and white households from 1870 to 2007. Black ownership increased by 46 percentage points, whereas white ownership increased by 20 points. Remarkably, 25 of the 26 point narrowing occurred between 1870 and 1910. Part of this early convergence is accounted for by falling white ownership due to movement out of agriculture, but most is accounted for by post-emancipation gains among blacks. After 1910, white and black households increased ownership, but the racial gap barely changed. We discuss the influence of residential segregation, public policy, and permanent income on the ownership gap.