USE OF EXPERT RATINGS AS SAMPLING STRATA FOR A MORE COST-EFFECTIVE PROBABILITY SAMPLE OF A RARE POPULATION

We consider situations in which externally observable characteristics allow experts to quickly categorize individual households as likely or unlikely to contain a member of a rare target population. This classification can form the basis of disproportionate stratified sampling such that households classified as "unlikely" are sampled at a lower rate than those classified as "likely," thereby reducing screening costs. Design weights account for this approach and allow unbiased estimates for the target population.We demonstrate that with sensitivity and specificity of expert classification at least 70%, and ideally at least 80%, our approach can economically increase effective sample size for a rare population. We develop heuristics for implementing this approach and demonstrate that sensitivity drives design effects and screening costs whereas specificity only drives the latter. We demonstrate that the potential gains from this approach increase as the target population becomes rarer. We further show that for most applications, unlikely strata should be sampled at 1/6 to ? the rate of likely strata.This approach was applied to a survey of Cambodian immigrants in which the 82% of households rated "unlikely" were sampled at ? the rate as "likely" households, reducing screening from 9.4 to 4.0 approaches per complete. Sensitivity and specificity were 86% and 91% respectively. Weighted estimation had a design effect of 1.26 so screening costs per effective sample size were reduced 47%. We also note that in this instance, expert classification appeared to be uncorrelated with survey outcomes of interest among eligibles.     

Risk Factors for Problematic Gambling: A Critical Literature Review

This article is a critical review of risk factors for pathological gambling categorized by demographics, physiological and biological factors, cognitive distortions, comorbidity and concurrent symptoms, and personality symptoms and characteristics. There is also a varia section (availability, parents playing, sensory characteristics, schedules of reinforcement, age of onset, and playing duration). The review found very few well established risk factors for pathological gambling (i.e. more than two studies to support the conclusions). Well established risk factors included demographic variables (age, gender), cognitive distortions (erroneous perceptions, illusion of control), sensory characteristics, schedules of reinforcement, comorbid disorders (OCD, drug abuse), and delinquency/illegal acts. An understanding of risk factors for pathological gambling should enhance prevention and treatment approaches.     

‘Don’t discriminate against minority nationalities’: practicing Tibetan ethnicity on social media

Through an analysis of popular posts Tibetans shared over the social media application WeChat in 2013 and 2014 and offline discussions about them, this paper shows how Tibetans living in and traveling through Xining City practiced and performed their ethnic identity in the face of perceived harassment. Through their viral posts, they created a cyber-community that contributed to Tibetan ethnic group formation when Tibetans interpreted their ethnic identity as the basis for unjust treatment by the Chinese state and private Han individuals. In online posts the Han are portrayed as harassing Tibetans after terror attacks across China, violating minzu rights, denigrating Tibetan culture and territory, and denying Tibetans equal footing as modern compatriots. Social media are changing the ‘representational politics’ of Tibetan ethnicity, altering participation in the representation of the Tibetan ethnic group. Still, online discourse remains subject to constraints; private offline discussions remain important fora of opinion exchange.     

The relationship between bankers and farmers: An analysis of Britain and Ireland

The financial sector is playing a more central role in agriculture. This article analyzes the external provision of finance for farmers in Britain and the Irish Republic, drawing principally on interviews with bankers and specialist providers of agricultural finance. The development of farm credit institutions in the two countries and their subsequent commercialization is discussed. Agriculture is commercially attractive to lenders as part of a balanced portfolio because of its stable, low risk character. Credit selectivity is confirmed as a feature of lender behaviour, although its consequences are likely to be more far reaching in Ireland. Lenders' perceptions of the financial sophistication of farmers is assessed, the more financially sophisticated farmer being more receptive to the logic of the financial sector and hence a more attractive customer. An emphasis on tax avoidance can lead farmers into irrational borrowing decisions. Larger farmers are better placed to take advantage of lending opportunities and new financial instruments.     

A Multi-Trait,Multi-Method Analysis of Three Career Development Measures

Campbell and Fiske's (1959) multi-trait, multi-method analysis was applied to three popular measures of career development. College students completed the Attitude Scale of the Career Maturity Inventory (Crites, 1978a), the Vocational Preference Inventory (Holland, 1978), and the Decision-Making Scale of the Career Development Inventory (Super, Thompson, Lindeman, Jordaan, & Myers, 1981). Participants also took part in a structured interview to assess their career development. The table of multi-trait, multi-method correlation coefficients for the three measures of career development supported their construct validity. Implications and ideas for future research are discussed.