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321.
LaBrie RA LaPlante DA Nelson SE Schumann A Shaffer HJ 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2007,23(3):347-362
Internet gambling is growing rapidly, as is concern about its possible effect on the public’s health. This paper reports the
results of the first prospective longitudinal study of actual Internet sports gambling behavior during eight study months.
Data include recorded fixed-odds bets on the outcome of sporting contests and live-action bets on the outcome of events within
contests for 40,499 Internet sports gambling service subscribers who enrolled during February 2005. We tracked the following
primary gambling behaviors: daily totals of the number of bets made, money bet, and money won. We transformed these variables
into measures of gambling involvement. We analyzed behavior for both fixed-odds and live-action bets. The median betting behavior
of the 39,719 fixed-odds bettors was to place 2.5 bets of €4 (approximately $5.3 US) every fourth day during the median 4 months
from first to last bet. This typical pattern incurred a loss of 29% of the amount wagered. The median betting behavior of
the 24,794 live-action bettors was to place 2.8 wagers of €4 every fourth day during the median duration of 6 weeks at a loss
of 18% of the amount wagered. We also examined the behavior of empirically determined groups of heavily involved bettors whose
activity exceeded that of 99% of the sample. 相似文献
322.
Weller CE 《Journal of aging & social policy》2007,19(1):21-38
Despite large public policy efforts over the past 30 years, a large minority of households remains consistently inadequately prepared for retirement. If policymakers want to address this shortcoming, public policy has to change from its current path. This paper suggests a system of mandatory private pensions funded by a minimum mandatory contribution of 3% of payroll. In addition, a number of institutional changes are suggested to reduce the costs and risks of individual accounts. 相似文献
323.
This article provides the most recent U.S. prevalence estimates of forced sex and unwanted sexual activity. Results of a national telephone survey conducted in 2001-2003 indicate that 1 in 59 U.S. adults (2.7 million women and 978,000 men) experienced unwanted sexual activity in the 12 months preceding the survey and that 1 in 15 U.S. adults (11.7 million women and 2.1 million men) have been forced to have sex during their lifetime. There were 60.4% of females and 69.2% of males who were 17 years old or younger at the time the first forced sex occurred. This study provides an update to the National Violence Against Women Survey with more recent national data. Findings suggest that victimization rates have remained consistent since the 1990s. These findings suggest that a continued effort toward primary prevention of sexual violence, particularly rape of children and adolescents, is needed. 相似文献
324.
The myth of problem-free living is easily identifiable in Western culture through its childhood fairy tales and modern love stories. Even if inadvertently, the field of mental health perpetuates this myth with the very concept of "mental health," which implies a state without suffering. Using mindfulness, Buddhists assume an alternative stance towards suffering: rather than eliminate it, they compassionately engage it. This article explores the potentials of mindfulness as an alternative approach to suffering within the context of marriage and family therapy. Family therapists can integrate mindfulness principles into their work to help clients shift how they relate to the unique forms of suffering that one encounters in intimate relationships, such as abuse, divorce, rejection, and loss. 相似文献
325.
326.
In recent years, a variety of regression models, including zero-inflated and hurdle versions, have been proposed to explain the case of a dependent variable with respect to exogenous covariates. Apart from the classical Poisson, negative binomial and generalised Poisson distributions, many proposals have appeared in the statistical literature, perhaps in response to the new possibilities offered by advanced software that now enables researchers to implement numerous special functions in a relatively simple way. However, we believe that a significant research gap remains, since very little attention has been paid to the quasi-binomial distribution, which was first proposed over fifty years ago. We believe this distribution might constitute a valid alternative to existing regression models, in situations in which the variable has bounded support. Therefore, in this paper we present a zero-inflated regression model based on the quasi-binomial distribution, taking into account the moments and maximum likelihood estimators, and perform a score test to compare the zero-inflated quasi-binomial distribution with the zero-inflated binomial distribution, and the zero-inflated model with the homogeneous model (the model in which covariates are not considered). This analysis is illustrated with two data sets that are well known in the statistical literature and which contain a large number of zeros. 相似文献
327.
328.
Daniel E. O'Leary 《决策科学》1987,18(3):468-486
This paper proposes a set of definitions for the concepts “validation” and “assessment” applied to expert systems (ESs). It develops a framework for this validation and demonstrates the framework on existing accounting and auditing ESs to elicit some of the research issues involved in ES validation. Validation is critical to the design and implementation of decision-making ESs. In a setting where objectivity is sought and variance is avoided, validation ascertains what a system knows, knows incorrectly, or does not know. Validation ascertains the system's level of expertise and investigates the theoretical basis on which the system is based. It evaluates the reliability of decisions made by the system. The validation framework developed in this paper is research methods. It is designed to reflect the unique aspects of ESs (in contrast to other types of computer programs) and can be used by ES developers as a basis from which to perform validation and by researchers as a framework to elicit research issues in validation. 相似文献
329.
This note examines the sensitivity of the basic economic-order-quantity inventory model to lot-size errors when holding costs are assumed to be a strictly increasing (though not necessarily linear) function of average inventory. In particular, we show that the penalty associated with ordering either too much or too little is a function not only of the size of the error but of the shape of the holding-cost curve as well. We demonstrate that, under certain conditions, even relatively small lot-size errors can be extremely costly. 相似文献
330.
Richard E. Rosenthal 《决策科学》1985,16(2):133-152
This paper attempts to isolate and analyze the principal ideas of multiobjective optimization. We do this without casting aspersions on single-objective optimization or championing any one multiobjective technique. We examine each fundamental idea for strengths and weaknesses and subject two—efficiency and utility—to extended consideration. Some general recommendations are made in light of this analysis. Besides the simple advice to retain single-objective optimization as a possible approach, we suggest that three broad classes of multiobjective techniques are very promising in terms of reliably, and believably, achieving a most preferred solution. These are: (1) partial generation of the efficient set, a rubric we use to unify a wide spectrum of both interactive and analytic methods; (2) explicit utility maximization, a much-overlooked approach combining multiattribute decision theory and mathematical programming; and (3) interactive implicit utility maximization, the popular class of methods introduced by Geoffrion, Dyer, and Feinberg [24] and extended significantly by others. 相似文献