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211.
The study objectives were to evaluate the correlates and psychosocial implications of internet gambling among adolescents, as well as the association between internet gambling and problematic internet use. A cross-sectional study design was applied among a random sample (N = 484) of adolescents (71.2% boys; 28.8% girls; mean age ± standard deviation, SD = 14.88 ± 0.55 years). Self-completed questionnaires, including internet gambling practices, internet use characteristics, Young Internet Addiction Test, and Strengths and Difficulties Questionnaire were utilized. The prevalence of internet gambling was 15.1%. Internet gambling was associated with psychosocial maladjustment, including Abnormal Conduct Problems (gender adjusted odds ratio, AOR = 3.83; 95% confidence interval, 95% CI: 1.86–7.92) and Borderline Peer Problems (AOR = 2.04; 95% CI: 1.09–3.85). The likelihood of concomitant problematic internet use was significantly higher among internet gamblers (AOR = 1.81; 95% CI: 1.03–3.19). Multivariate regression analyses indicated that among all characteristics of internet use assessed, utilizing the internet for the purposes of gambling practices was independently associated with problematic internet use among adolescents (AOR = 3.43; 95% CI: 1.40–8.39). Thus, the study findings suggest that adolescents who participate in internet gambling practices are more likely to concomitantly present with problematic internet use.  相似文献   
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This paper explores how founders’ blueprints affect the dynamism of organizational practices, and in particular the capability to sustain as well as change practices. First, a theoretical argument is developed on the critical role of founders’ blueprints of the employment model, which are difficult to alter and mark firms’ future paths by affecting the dynamism of organizational practices over an extended period of time. Subsequently, case studies of several organizational practices in three management consulting firms in the USA, the Netherlands and the UK illustrate how founders’ conceptions of the employment relationship (i.e. their employment model) affect the way in which competing demands of continuity and renewal are addressed. Moreover, engineering‐ or commitment‐oriented blueprints appear to facilitate the capability to adapt, while autocratic blueprints do not.  相似文献   
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This paper presents a combined Facility Location/Network Design Problem which simultaneously considers the location of facilities and the design of its underlying network so as to minimize the maximum customer-facility travel time. The model generalizes the classical p-center problem and has various applications in regional planning, distribution, telecommunications, emergency systems, and other areas. Two mixed integer programming formulations are presented and compared. Several valid inequalities are derived for the most promising of these formulations to strengthen its LP relaxation bound and to reduce the enumeration tree. Numerical results of a series of computational experiments for instances with up to 100 nodes and 500 candidate links are reported.  相似文献   
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Helping professions address the growing number of social problems which have emerged, along with contextual changes in Russian society, culture and state social policy. Social work only emerged in Russia in 1991 and it still lacks recognition by public opinion and by other caring professions. This paper addresses the current development of the social work profession in Russia, considers its context and reviews the main issues affecting processes within social work practice and education. Many social work agencies are in search of new forms of organization and are trying to develop new philosophies of service, in order to build positive relations with communities. However, given the 70 years of the Soviet era when social protection was highly centralized and bureaucratized, the organizational cultures of the new social services sometimes reproduce old patterns of bureaucracy, especially where employees lack professional education. The reflective practitioner type of professionalism is here argued to be more appropriate for social workers in today's Russia. The paper includes an analysis of interviews with social workers and administrators in a large Russian city and considers the results of an ethnographic study of social services in the same city.  相似文献   
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While most of the literature on measurement error focuses on additive measurement error, we consider in this paper the multiplicative case. We apply the Simulation Extrapolation method (SIMEX)—a procedure which was originally proposed by Cook and Stefanski (J. Am. Stat. Assoc. 89:1314–1328, 1994) in order to correct the bias due to additive measurement error—to the case where data are perturbed by multiplicative noise and present several approaches to account for multiplicative noise in the SIMEX procedure. Furthermore, we analyze how well these approaches reduce the bias caused by multiplicative perturbation. Using a binary probit model, we produce Monte Carlo evidence on how the reduction of data quality can be minimized. For helpful comments, we would like to thank Helmut Küchenhoff, Winfried Pohlmeier, and Gerd Ronning. Sandra Nolte gratefully acknowledges financial support by the DFG. Elena Biewen and Martin Rosemann gratefully acknowledge the financial support by the Federal Ministry of Education and Research (BMBF). The usual disclaimer applies.  相似文献   
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A nonparametric control chart for variance is proposed. The chart is constructed following the change-point approach through the recursive use of the squared ranks test for variance. It is capable of detecting changes in the behaviour of individual observations with performance similar to a self-starting CUSUM chart for scale when normality is assumed, and a relatively better power when assessing nonnormal observations. A comparison is also made with two equivalent nonparametric charts based on Mood and Ansari-Bradley statistics. When dealing with symmetrical distributions, the proposed chart shows smaller (better) out-of-control average run length (ARL), and a competing performance otherwise. In addition, sensitivity to changes in mean and variance at the same time was tested. Extensive Monte Carlo simulation was used to measure performance, and a practical example is provided to illustrate how the proposed control chart can be implemented in practice.  相似文献   
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This paper deals with the asymptotics of a class of tests for association in 2-way contingency tables based on square forms in cell frequencies, given the total number of observations (multinomial sampling) or one set of marginal totals (stratified sampling). The case when both row and column marginal totals are fixed (hypergeometric sampling) was studied in Kulinskaya (1994), The class of tests under consideration includes a number of classical measures for association, Its two subclasses are the tests based on statistics using centralized cell frequencies (asymptotically distributed as weighted sums of central chi-squares) and those using the non-centralized cell frequencies (asymptotically normal). The parameters of asymptotic distributions depend on the sampling model and on true marginal probabilities. Maximum efficiency for asymptotically normal statistics is achieved under hypergeometric sampling, If the cell frequencies or the statistic as a whole are centralized using marginal proportions as estimates for marginal probabilities, the asymptotic distribution does not differ much between models and it is equivalent to that under hypergeometric sampling. These findings give an extra justification for the use of permutation tests for association (which are based on hypergeometric sampling). As an application, several well known measures of association are analysed.  相似文献   
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