A COLLABORATIVE LEARNING LAB: DOES THE FORM MATTER?

A recent paper found that adding a collaborative learning lab (CLL) component to a traditional introductory microeconomics class significantly improved students' scores on a standardized final exam. Here, the authors reconsider these results in two fundamental ways. First, this article is able to include student-specific factors, such as standardized test scores and age, to control for a student's desire and ability to perform. These results suggest that they slightly underestimate the gains from CLL classes. The second question addressed concerns the implementation of the CLL component. In the original work, the CLL class contained only 24 students in class (small-CLL). This paper introduces the CLL component into a class with 48 students (largE-CLL). The authors found students attending a large in-class CLL failed to perform significantly better on a standardized test than students attending classes without an in-class CLL. They also performed significantly worse than students in a small-CLL environment. This article suggests that a CLL can improve scores if care is taken to both maintain an environment that maximizes student–instructor interaction and monitors student collaboration.     

Nonlinearity in dynamic adjustment: Semiparametric estimation of panel labor supply

We estimate a semiparametric dynamic panel data model by the local linear kernel method and we interpret the slope of the nonparametric component function as a varying slope coefficient. Thus, the slope coefficient is a smooth, but otherwise unknown, function of some of the regressors. A Monte Carlo experiment is reported to examine the finite sample performance of the local linear estimator. We apply the estimation method to a labor supply equation for men from the triannual Survey of Income and Program Participation (SIPP). Specification tests based on the estimated labor supply elasticities, partial adjustment coefficients, and residuals demonstrate the improvements from a semiparametric partially linear model. Our empirical results point to a need by economists to revisit the issue of the speed of labor market adjustment to policy induced shifts in labor demand and to take more formal econometric account of heterogeneity in wage effects when studying the distributional consequences of tax reforms for labor supply earnings. First version received: July 2000/Final version received: January 2001     

Intertemporal substitution and the liquidity effect in a sticky price model

The liquidity effect, defined as a decrease in nominal interest rates in response to a monetary expansion, is a major stylized fact of the business cycle. This paper first confirms that, with separable preferences, a low degree of intertemporal substitution in consumption is a necessary condition for the existence of the liquidity effect. In contrast to this result, in a model with non-separable preferences and capital accumulation it takes an implausibly high elasticity of intertemporal substitution to produce a liquidity effect. The robustness of these results to alternative degrees of nominal rigidities, capital adjustment costs and stochastic monetary processes is also analysed. We conclude that price stickiness, by itself, does not guarantee the existence of a liquidity effect.     

发展中国家的普遍服务政策

该文构建非对称信息模型分析普遍服务政策问题,其中政府对企业在农村提供服务的边际成本具有非对称信息.该文对区别定价和统一定价两种情形进行了对比分析.在实施区别定价时,不完全信息将提高农村地区的资费水平,并且降低相应的网络覆盖面积;而在实施统一定价时,农村地区的定价可能降低,但却是以网络覆盖的减少为代价的.该文的政策结论是:在实施普遍服务政策时,需要综合考虑网络投资的激励和用户承受能力.     

Monetising the Classical Equations: a theory of circulation

The Classical Equations describe output and income in real terms.To use them to analyse aggregate demand, the transactions theydescribe must be ‘monetised’. A sum of money equalto the wage bill of the capital goods sector can be shown tobe necessary and sufficient to carry out all transactions, ina process of circulation which also defines an expression forvelocity. When money has intrinsic value, the quantity approachmay hold in the short run but, in the long run, money will beendogenous. In these conditions, the rate of interest will bedetermined by the supply and demand for reserves, but when moneyis purely nominal, only a minimum rate will be fixed, and therate of interest will have to be pegged. The Appendix developsthe Classical Equations and shows that they define an invariableunit of account.     

On the Composition of Committees

This article is concerned with the role of committees in collectivedecision making processes in a world where agents must be motivatedto collect information. Committees improve the quality of decisionmaking by providing information and by coordinating the collectionof information. We address two types of questions. First, howdoes the composition of a committee affect final decisions?Second, what is the optimal composition of a committee fromthe decision maker's point of view? As to the latter question,we show that the cost of information collection plays an importantrole. If this cost is low, then the preferences of the committeemembers should be aligned to those of the decision maker. Memberswith similar preferences as the decision maker collect the properpieces of information. Moreover, manipulation of informationdoes not occur if the preferences of the decision maker andthe members are consonant. If the cost of searching is high,then the committee should be composed of members with polarizedpreferences. Outliers have a strong incentive to search forinformation.     

Altruism and the Economic Values of Environmental and Social Policies

Altruism is a type of non-use value which can have different definitions depending on the type of goods entering the utility function of the altruists and their expectations about the contributions of others. The purpose of this paper is to measure the trade-offs between different types of altruist values originating from social and environmental policies. Environmental policies are concerned with reducing health effects from a power plant while social policies involve both the attainment of public facilities for education and leisure and an increase in the income of the affected population. The empirical application utilizes a choice experiment technique which allows for valuation of multiple goods. Health effects are decomposed into the values of the risk of becoming ill, the duration of the episodes and the limitations imposed by illness. Altruist values are elicited from a population that is not affected by pollution. Results show that altruism is significant for policies directed to reducing health effects and improving the income level of the affected population, whereas there is egoism for a policy aimed at improving public facilities in the polluted suburb. The value of altruism is significantly influenced by the expectations of net benefits to be received by the affected population.     

Money, Sex and Happiness: An Empirical Study

The links between income, sexual behavior and reported happiness are studied using recent data on a sample of 16,000 adult Americans. The paper finds that sexual activity enters strongly positively in happiness equations. Higher income does not buy more sex or more sexual partners. Married people have more sex than those who are single, divorced, widowed or separated. The happiness‐maximizing number of sexual partners in the previous year is calculated to be 1. Highly educated females tend to have fewer sexual partners. Homosexuality has no statistically significant effect on happiness.