从丝绸之路到石油之路

丝绸之路千年之后又获重生,尽管现在称它石油之路更为合适.现在丝绸(且不提电脑部件、衣服和玩具)依旧由东流向西,但石油却正在向东奔流,而且不久天然气也会加入其中.     

Does Medicare Coverage Improve Cancer Detection and Mortality Outcomes?

Medicare is a large government health insurance program in the United States that covers about 60 million people. This paper analyzes the effects of Medicare insurance on health for a group of people in urgent need of medical care: people with cancer. We used a regression discontinuity design to assess impacts of near-universal Medicare insurance at age 65 on cancer detection and outcomes, using population-based cancer registries and vital statistics data. Our analysis focused on the three tumor sites for which screening is recommended both before and after age 65: breast, colorectal, and lung cancer. At age 65, cancer detection increased by 72 per 100,000 population among women and 33 per 100,000 population among men; cancer mortality also decreased by nine per 100,000 population for women but did not significantly change for men. In a placebo check, we found no comparable changes at age 65 in Canada. This study provides the first evidence to our knowledge that near-universal access to Medicare at age 65 is associated with improvements in population-level cancer mortality.     

The Importance of Voluntary Associations for Guerrilla Movements

The question I examine in this article is why is it that under certain circumstances a guerrilla movement succeeds while under others it fails? The hypotheses that I shall present below are the greater the number and variety of voluntary associations supporting the guerrilla movement, compared with the number of associations supporting the regime, the greater is the guerillas’ level of success. Voluntary associations can fulfill the guerrilla's basic needs: resources, organizational ability, and obligation. Achieving these needs assist the guerrilla in realizing: population support; inter-class allies; military force; governmental function, which in turn allows the realization of the political objectives.     

Cognitive psychologists as expert witnesses

The first part of this paper defines a central problem for professional ethics: whether agents in professional roles are to act on their own moral perceptions or rather defer to those with special authority to make decisions within particular institutional settings. Specifically, should the psychologist decide for himself whether and how to testify as an expert witness, or should he allow the judge and lawyer to settle these questions for him? I argue that he must decide for himself and attempt to control the nature of his testimony. Given this preliminary conclusion, the second part of the paper argues on direct moral grounds first for a general presumption in favor of psychologists' testimony on the accuracy of eyewitnesses. Such testimony fits the legal criterion of reasonable doubt, if the psychologists' information is more accurate than that of the average juror and lawyer. Second, it is argued that the expert witness must resist intense adversarial pressures and present his testimony as impartially and objectively as possible.