This paper develops a methodology for consistently estimating the relative weights in senator utility functions, despite the fact that senator ideologies are unobserved. The empirical results suggest that voter preferences are assigned only one quarter of the weight in senator utility functions. The national "party line" also has some influence, but the senator's own ideology is the primary determinant of roll-call voting patterns. These results cast doubt on the empirical relevance of the median voter theorem. Estimation of the model requires only roll-call voting data, making it widely applicable.

This paper develops a methodology for consistently estimating the relative weights in senator utility functions, despite the fact that senator ideologies are unobserved. The empirical results suggest that voter preferences are assigned only one quarter of the weight in senator utility functions. The national 'party line' also has some influence but the senator's own ideology is the primary determinant of roll-call voting patterns. These results cast doubt on the empirical relevance of the median voter theorem. Estimation of the model requires only roll-call voting data, making it widely applicable.

Most analyses treat global warming as a single-agent problem. The present study presents the Regional Integrated model of Climate and the Economy (RICE) model. By disaggregating into countries, the model analyzes different national strategies in climate-change policy: pure market solutions, efficient cooperative outcomes, and noncooperative equilibria. This study finds that cooperative policies show much higher levels of emissions reductions than do noncooperative strategies; that there are substantial differences in the levels of controls in both the cooperative and the noncooperative policies among different countries; and that high-income countries may be the major losers from cooperation.

Panel and time-series data describing the green-revolution period in India are used to assess the effects of exogenous technical change on the returns to schooling, the effects of schooling on the profitability of technical change, and the effects of technical change and school availability on household schooling investment. The results indicate that the returns to (primary) schooling increased during a period of rapid technical progress, particularly in areas with the highest growth rates. Such increases induced private investment in schooling, net of changes in wealth, wages, and the availability of schools, and school expansion importantly increased levels of schooling.