[Review of] Paul R. Spickard. Mixed Blood-Intermarriage and Ethnic Identity in Twentieth-Century America

Just as the mixing of peoples has been a dominant theme in American social history, it has also been a compelling, if not controversial, theme in American social science. Sociologists have long recognized that intermarriage is an important social phenomenon in American society. Thus, early American social observers were drawn to study this area of social life. From Frederick Hoffman\u27s earliest studies of black/white couples in the late nineteenth century to W. E. B. Du Bois\u27s observations on intermarriage at the beginning of the twentieth century, the systematic study of inter-marriage stands as one of the initial starting points for American sociology

Consumer Acceptance of Genetically Modified Foods: Traits, Labels and Diverse Information

New experimental economic methods are described and used to assess consumers'�willingness to pay for food products that might be made from new transgenic and intragenic�genetically modified (GM) traits. Participants in auctions are randomly chosen adult consumers�in major US metropolitan areas and not college students. Food labels are kept simple and focus�on key attributes of experimental goods. Diverse private information from the agricultural�biotech industry (largely Monsanto and Syngenta), environmental groups (largely Greenpeace�and Friends of the Earth) and independent third-party information is used to construct the�information treatments. Food labels and information treatments are randomized, which is a�deviation from traditional lab methods. Auctions are best described as sealed bid random n-th�price and not the standard Vickery 2nd price auctions. I show that participants in these�experiments respond to both food labels and information treatments, but no single type of�information is dominant�

Setting Incentives for Collaboration Among Agricultural Scientists: Application of Principal-Agent Theory to Team Work

�The USDA is attempting to shift more research funds into competitive grants involving collaboration across disciplines on large projects. This type of research structure raises a host of information and incentive issues. The objective of this paper is to shed new light on principal-agent problems that are likely to arise in this new funding structure.incentives; Principal-agent model; team research; competitive grants; multi-disciplinary research

The Status of Labor-Saving Mechanization in Fruits and Vegetables

�The objective of this paper is to examine the status of labor-saving mechanization in U.S. fruit and vegetable harvesting. Fruit and vegetable harvest mechanization has several potential advantages: reduced harvest costs, eliminate problems associated with finding good quality harvest labor, permit longer harvesting days, and reduce exposure of harvest to human bacteria.�������� Commercial mechanical harvesters for processed tomatoes, cucumbers, peppers, carrots, tart cherries, apples, grapes, peaches, plums and grapes are in the hands of growers. To my surprise, considerable progress has been made on fresh market sweet cherry, apple and berry harvesters, and in the next few years commercial sales of these machines are expected. A negative shock to labor harvest-labor availability or jump in the harvester wage or piece rate could rapidly accelerate adoption of the best mechanical harvesting technologies by growers and processors. �mechanized harvesting; fruits; vegetables; processing; fresh market; labor availability; United States

THE WATER RESOURCE PROBLEM

Resource /Energy Economics and Policy,

Setting Incentives for Scientists Who Engage in Research and Other Activities: An Application of Principal-Agent Theory

 The objective of this paper is to develop an optimal incentive system for multitaskingscientists in universities or professors under repeat contracting. With the aid of a principalagentmodel under repeat contracting, we show that (i) when a second task is assigned to aprofessor and the two tasks are related, the size of the optimal incentive rate for the first task isreduced in some situations but not others relative to that of a single task, (ii) with an increasein the noise in the technical relationship of the second task or imprecision in outputmeasurement, the optimal incentive rate for that task is reduced and for the first task may bereduced or increased , (iii) with greater efficiency of the professor in producing the secondoutput, as reflected in ability relative to cost of effort, the optimal incentive rate for the firsttask generally decreases, (iv) if the output of the professor’s two tasks are negativelycorrelated then the optimal incentive rate on the first task declines as the size of thiscorrelation increases. The size of the guarantee is always reduced as the professor’s ability fora task increases, but is increased as his cost of effort, noisiness of the technology ormeasurement of output, or correlation between the two outputs increases. It is also possiblethat, as a professor undertakes several difficult-to-measure tasks, the incentive rate will bereduced to the point that an optimal compensation system will involve only a guaranteedsalary, which is a very weak incentive for effort. Selective audits may be useful in thesesituations.incentives; Principal-agent model; Multitask; scientists; professors; respeat contracting; linear contracts

Flexibly Instructable Agents

This paper presents an approach to learning from situated, interactive tutorial instruction within an ongoing agent. Tutorial instruction is a flexible (and thus powerful) paradigm for teaching tasks because it allows an instructor to communicate whatever types of knowledge an agent might need in whatever situations might arise. To support this flexibility, however, the agent must be able to learn multiple kinds of knowledge from a broad range of instructional interactions. Our approach, called situated explanation, achieves such learning through a combination of analytic and inductive techniques. It combines a form of explanation-based learning that is situated for each instruction with a full suite of contextually guided responses to incomplete explanations. The approach is implemented in an agent called Instructo-Soar that learns hierarchies of new tasks and other domain knowledge from interactive natural language instructions. Instructo-Soar meets three key requirements of flexible instructability that distinguish it from previous systems: (1) it can take known or unknown commands at any instruction point; (2) it can handle instructions that apply to either its current situation or to a hypothetical situation specified in language (as in, for instance, conditional instructions); and (3) it can learn, from instructions, each class of knowledge it uses to perform tasks.Comment: See http://www.jair.org/ for any accompanying file

The Role of Agriculture and Human Capital in Economic Growth: Farmers, Schooling, and Health

This survey reviews the existing literature, identifying the contribution of agriculture, schooling, and nutrition to economic growth and development over time and across countries. Particular attention is paid to the roles of improvements in agricultural technology and of the human capital of farmers and farm people. Macroeconomic and microeconomic evidence related to the interactions between human capital, productivity and real income per capita have occurred over the past 250 years. We show that for most countries, development is a process of conversion from primarily agrarian economies to urban industrial and service economies. The evidence is that positive technology shocks to agriculture have played a key role in igniting a transition from traditional to modern agriculture and to long-term economic growth in almost all countries. Improvements in agricultural technologies improve labor productivity and create surplus agricultural labor that can provide workers for the growing urban areas. In some cases, improved nutrition helps raise labor productivity and allows individuals to work for longer hours, which makes human capital investments more attractive. The induced improvements in the skill level of a population have major implications for raising living standards, improving health standards, and altering time allocation decisions. In most currently poor and middle income countries, improved schooling has been more important than improved nutrition or caloric intake in explaining recent economic growth. Nevertheless, the poorest countries of the world continue to have a large share of their labor force in agriculture, and growth cannot occur until they experience their own agricultural transformation.

An Economic Analysis of the Impact of Food Prices and Other Factors on Adult Lifestyles: Choices of Physical Activity and Healthy Weight

This paper examines women’s and men’s decisions to participate in physical activity and to attain a healthy weight. These outcomes are hypothesized to be related to prices of food, drink and health care services and products, the respondent’s personal characteristics (such as education, reading food labels, adjusted family income, opportunity cost of time, occupation, marital status, race and ethnicity) and his or her BMI at age 25. These decisions are represented by a trivariate probit model that is fitted to data for adults in the NLSY79 panel with geocodes that have been augmented with local area food, drink and health care prices. Separate analyses are undertaken for men and women due to basic physiological differences. Results include: Women and men who read food labels are more likely to participate in moderate and vigorous physical exercise, and women are less likely to be obese. Women with more education are more likely to be obese but educated men are less likely to be obesity. Higher prices for fresh fruits and vegetables and non-alcoholic drinks increase likelihood of obesity for females but not for males; and a higher price for processed fruits and vegetables reduce likelihood of obesity for females but not for males. A larger BMI at age 25 has wage effects later in life and also increases the probability of being obese.Physical Activity, Obesity, Food Prices, Adult, United States, Consumer/Household Economics, Health Economics and Policy, Labor and Human Capital, I10, D10, J24,