this study took an epidemiological approach toward the problem of drug addiction in tehran. the subjects were 300 addicts chosen on the basis of stratified random selection out of the population of 3627 prisoners who were all proven addicts and sentenced to imprisonment by the court in the year 1370. a descriptive survey showed that drug addiction generally, and heroin addiction specifically, i...

INTRODUCTION With the progression of substance dependence, drug cue-related brain activation is thought to shift from motivational towards habit pathways. However, a direct association between cue-induced brain activation and dependence duration has not yet been shown. We therefore examined the relationship between alcohol cue-reactivity in the brain, cue-induced subjective craving and alcohol ...

In this paper we examine rigorously the evidence for dependence among data size, transfer rate, and duration in Internet flows. We emphasize two statistical approaches for studying dependence, including Pearson’s correlation coefficient and the extremal dependence analysis method. We apply these methods to large data sets of packet traces from three networks. Our major results show that Pearson...

This paper studies “duration dependence”—the probability that a longer unemployment spell reduces a worker’s job opportunities —by sending fictitious resumes to real job postings across the U.S. We randomly manipulate the length of the current unemployment spell on each fictitious resume, and we track callbacks for interviews for all submissions. Preliminary results from the ongoing field exper...