Academic incentives for students can increase participation in and effectiveness of a physical activity program

The authors sought to determine whether a greater academic incentive would improve the effectiveness and student adherence to a 12-week voluntary exercise program designed to decrease students' percentage of body fat. They randomly assigned 210 students to 1 of 2 groups with different academic reward structures. The group with the greater reward structure showed better exercise adherence and lost more body fat than those without the additional incentive. These findings suggest that an academic incentive can increase overall student adherence to a voluntary exercise program and can boost the effectiveness of the program in a university environment. The findings also have potential implications for on-campus promotion of physical activity.     

Gambling Screens: Does Shortening the Time Frame Affect their Psychometric Properties?

Gambling screening tools such as the South Oaks Gambling Screen (SOGS) and a DSM-IV Screen for Gambling Problems (NODS) developed by the National Opinion Research Council have psychometrically validated lifetime and past-year versions. As research questions often dictate shorter time intervals, researchers have adapted the time frames of these instruments to their specific purposes without examining whether changing the time frame affects the psychometric properties. In this study, 3-month versions of SOGS and NODS were administered to a sample of 80 pathological gamblers (59 men, 21 women, mean age 44) seeking treatment at a state-funded facility. The 3-months versions had good internal consistency, good convergent validity with each other, with gambling behaviors assessed via the timeline followback method, and with measures of impulsivity. The 3-month versions also showed good discriminant validity with demographic variables and a measure of verbal IQ. Together the data indicate that shortening the time frame to 3 months does not seem to have adverse effects on the psychometric properties of SOGS and NODS. Thus these adapted versions could profitably be used for shorter time intervals, including as pre/post-treatment and follow-up measures in treatment outcome studies.     

Guilty or not? A path model of women's sexual force fantasies

This study estimated a path model of women's forceful sexual fantasies. Constructs examined were childhood sexual abuse, feminist beliefs, sexual guilt, erotophilia, and sexual experience. The study clarifies how these factors mediate one another in relationship to forceful sexual fantasies, and is first to examine the effects of feminist beliefs on forceful sexual fantasy. Adult women (N = 261) participated by completing an online survey. A path from sex guilt to forceful sexual fantasy, mediated by erotophilia, was found, wherein low levels of sex guilt and high levels of erotophilia were found to predict forceful sexual fantasy. A direct path between childhood sexual abuse and forceful sexual fantasy was also found. The resulting model is discussed in relation to previously-proposed theories on the role of force in women's sexual fantasies.     

Perspectives of college students and their primary health care providers on substance abuse screening and intervention

The authors conducted a needs assessment among students and health-care providers of a southwestern university health center with the goal of developing health-care-provider training addressing substance-abuse screening and intervention. They collected data from focus groups of undergraduate students and structured interviews and questionnaires with health-care providers. They identified gaps in provider and student perspectives on the extent of substance abuse on campus and the perceived roles of health-care providers and patients in screening and conducting interventions for substance abuse. These findings suggest that training for college health-care providers regarding substance-abuse brief screening and intervention should emphasize confidentiality of student medical records, the importance of nonjudgmental attitudes toward students, and the role of the provider as one who is competent and appropriate to address substance abuse. Such training should also educate providers about the types of substances students are using.     

It’s Not What You Know, but How You Use It: Statistical Knowledge and Adolescent Problem Gambling

This paper examined the nature of irrational gambling-related cognitions in a sample of 926 adolescents (mean age = 14.5 years) sampled from Australian schools. Students were differentiated according to gambling status and administered a series of items that assessed their understanding of objective odds, the nature of randomness, the role of skill in gambling, and the perceived profitability of gambling. The results confirmed previous findings that problem gamblers tend to be more irrational in their perceptions, as indicated by stronger beliefs in the role of skilful play in chance activities, and that gambling is a potentially profitable activity. However, counter intuitively, problem gamblers did not appear to have any poorer understanding of objective probabilities. These results are discussed in terms of Sevigny and Ladouceur’s (2004) concept of cognitive switching as well as psychological research concerning the role of emotional and motivational factors in the development of an illusion of control. The implications of these findings for gambling education programs are discussed.

Refined Inference on Long Memory in Realized Volatility

There is an emerging consensus in empirical finance that realized volatility series typically display long range dependence with a memory parameter (d) around 0.4 (Andersen et al., 2001 Andersen , T. G. , Bollerslev , T. , Diebold , F. X. , Labys , P. ( 2001 ). The distribution of realized exchange rate volatility . Journal of the American Statistical Association 96 ( 453 ): 42 – 55 .[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]; Martens et al., 2004 Martnes , M. , Van Dijk , D. , De Pooter , M. ( 2004 ). Modeling and forecasting S&P 500 volatility: Long memory, structural breaks and nonlinearity. Tinbergen Institute Discussion Paper 2004-067/4 . [Google Scholar]). The present article provides some illustrative analysis of how long memory may arise from the accumulative process underlying realized volatility. The article also uses results in Lieberman and Phillips (2004 Lieberman , O. , Phillips , P. C. B. ( 2004 ). Expansions for the distribution of the maximum likelihood estimator of the fractional difference parameter . Econometric Theory 20 ( 3 ): 464 – 484 . [Google Scholar], 2005 Lieberman , O. , Phillips , P. C. B. ( 2005 ). Expansions for approximate maximum likelihood estimators of the fractional difference parameter . The Econometrics Journal 8 : 367 – 379 . [Google Scholar]) to refine statistical inference about d by higher order theory. Standard asymptotic theory has an O(n ^?1/2) error rate for error rejection probabilities, and the theory used here refines the approximation to an error rate of o(n ^?1/2). The new formula is independent of unknown parameters, is simple to calculate and user-friendly. The method is applied to test whether the reported long memory parameter estimates of Andersen et al. (2001 Andersen , T. G. , Bollerslev , T. , Diebold , F. X. , Labys , P. ( 2001 ). The distribution of realized exchange rate volatility . Journal of the American Statistical Association 96 ( 453 ): 42 – 55 .[Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) and Martens et al. (2004 Martnes , M. , Van Dijk , D. , De Pooter , M. ( 2004 ). Modeling and forecasting S&P 500 volatility: Long memory, structural breaks and nonlinearity. Tinbergen Institute Discussion Paper 2004-067/4 . [Google Scholar]) differ significantly from the lower boundary (d = 0.5) of nonstationary long memory, and generally confirms earlier findings.