THE WELFARE IMPLICATIONS OF MORAL HAZARD AND ADVERSE SELECTION IN COMPETITIVE INSURANCE MARKETS

I model a competitive insurance market with both moral hazard and adverse selection, and analyze the effect on welfare when both problems are present simultaneously. An examination of the interaction between these two problems leads to two hypotheses. First, the nature of the equilibrium contracts is such that each problem partially offsets the welfare loss associated with the other. And second, the degree to which this occurs increases as agents become more heterogeneous. Simulation results overwhelmingly support both hypotheses.     

Premarital Cohabitation and Housework: Couples in Cross‐National Perspective

The authors examine the effect of premarital cohabitation on the division of household labor in 22 countries. First, women do more routine housework than men in all countries. Second, married couples that cohabited before marriage have a more equal division of housework. Third, national cohabitation rates have equalizing effects on couples regardless of their own cohabitation experience. However, the influence of cohabitation rates is only observed in countries with higher levels of overall gender equality. The authors conclude that the trend toward increasing cohabitation may be part of a broader social trend toward a more egalitarian division of housework.     

Nonresponse weighting adjustment using estimated response probability

To reduce nonresponse bias in sample surveys, a method of nonresponse weighting adjustment is often used which consists of multiplying the sampling weight of the respondent by the inverse of the estimated response probability. The authors examine the asymptotic properties of this estimator. They prove that it is generally more efficient than an estimator which uses the true response probability, provided that the parameters which govern this probability are estimated by maximum likelihood. The authors discuss variance estimation methods that account for the effect of using the estimated response probability; they compare their performances in a small simulation study. They also discuss extensions to the regression estimator.     

Training with o (observing) and T (treatment) teams in live supervision: reflections in the looking glass*

Working with a treatment and observing team at the same time, behind the oneway mirror, offers a variety of ways to: (a) generate multiple realities; (b) work with two different models of family therapy simultaneously; and (c) provide feedback on the teams' own roles, rules and group process. The process that 6 trainees and two supervisors used with T and O teams to examine their own coevolution as a therapeutic system using the Milan model of family therapy and Ericksonian hypnotherapy is described. The article concludes with a discussion of the advantages and pitfalls of this type of dual supervision.     

Individual behavior under risk and under uncertainty: An experimental study

These experiments are concerned with individual behavior under risk and under uncertainty. By exploiting the isolation effect the experiments were able to offer to 134 subjects the possibility of actually gaining or losing an important sum of money.The experimental data show that under risk as well as under complete ignorance the subjects' attitudes towards prospects of gains and towards prospects of losses are totally unrelated.The data also show that when facing prospects of gains, the subjects generally take the exact probabilities of the events into account, whereas, when facing prospects of losses many of then have only recourse to coarser categories of plausibility, or even no longer use their information at all.     

New venture development at Du Pont

New Products are the life blood of a growing company, but traditional methods of introducing new products are no longer adequate. Du Pont is using a new approach called Venture Management. A New Venture Development provides an ideal environment for making and carrying out decisions involved in introducing new technological developments. It combines the advantages in mobility and communications enjoyed by a small venture-orientated company with the strong technical and financial advantages of a large company.     

Fertility incentives and participation in localities with limited means: a dynamic model of per capita resources

Several countries have attempted to change human fertility through economic incentives. This paper presents simple mathematical models of the participation of couples in a locally funded program of economic incentives. The models take as a springboard China's one-child program. Localities with low per capita incentives attract few couples to the program, while localities with high incentives attract many couples at first, but the value of the benefits is then watered down. The models show that participation in the program may persistently oscillate or may decay to a stationary level. Which behavior occurs is determined by whether there are decreasing, constant, or increasing returns in the rates of participation in response to successive equal increments in the incentive offered, and by the extent to which prospective parents learn from experience with past oscillations in the incentives. The models raise many empirical questions about the dynamics of incentive programs.