As an effective way to solve information overload, recommender system has drawn attention of scholars from various fields. However, existing works mainly focus on improving the accuracy of recommendation by designing new algorithms, while the different importance of individual users has not been...

This paper illustrates two techniques for calculating the statistical significance of the marginal effects derived from Heckman?s sample selection model,an increasingly common econometric specification in political science. The discussion draws on an analysis by Sweeney (2003) of the incidence...

Mediation in peacekeeping missions and the role of dispute severity, time pressure, and the peacekeeper's rank in that process are investigated. A set of hypotheses concerning the effects of these factors is developed. A test of the hypotheses reveals that dispute severity has a strong effect on...

This paper illustrates two techniques for calculating the statistical significance of the marginal effects derived from Heckman’s sample selection model,an increasingly common econometric specification in political science. The discussion draws on an analysis by Sweeney (2003) of the incidence...