Meditation lowers stress and supports forgiveness among college students: a randomized controlled trial

OBJECTIVE AND PARTICIPANTS: The authors evaluated the effects on stress, rumination, forgiveness, and hope of two 8-week, 90-min/wk training programs for college undergraduates in meditation-based stress-management tools. METHODS: After a pretest, the authors randomly allocated college undergraduates to training in mindfulness-based stress reduction (MBSR; n = 15), Easwaran's Eight-Point Program (EPP; n = 14), or wait-list control (n = 15). The authors gathered pretest, posttest, and 8-week follow-up data on self-report outcome measures. RESULTS: The authors observed no post-treatment differences between MBSR and EPP or between posttest and 8-week follow-up (p > .10). Compared with controls, treated participants (n = 29) demonstrated significant benefits for stress (p < .05, Cohen's d = -.45) and forgiveness (p < .05, d = .34) and marginal benefits for rumination (p < .10, d = -.34). CONCLUSIONS: Evidence suggests that meditation-based stress-management practices reduce stress and enhance forgiveness among college undergraduates. Such programs merit further study as potential health-promotion tools for college populations.     

Long-term safety of stimulant medications used to treat children with ADHD

Attention-deficit/hyperactivity disorder (ADHD) is a common mental health condition that affects children, adolescents, and adults. Because it is a chronic condition and typically requires effective treatment for several years or more, information on the benefits and risks of long-term pharmacotherapy for ADHD is vital to clinicians. This article reviews the emerging literature on the safety of long-term stimulant medications in ADHD-the most commonly prescribed medications for this condition. Common side effects, including cardiovascular effects, growth effects, and tics, are discussed, as well as treatment of children younger than age 6 and evidence of carcinogenic and reproductive effects.     

Taking Rights Structurally: Disability, Rights and Social Worker Responses to Direct Payments

Correspondence to: Tim Stainton, School of Social Work and Family Studies, University of British Columbia, 2080 West Mall, Vancouver, BC, Canada, V6T 1Z2. E-mail: timst{at}interchange.ubc.ca Summary This article examines the link between a justice and rightsdiscourse and disability policy and practice. Specifically,it considers social worker responses to direct payments, a policywhich has been linked to a discourse of social justice and rights.The article initially considers the nature of justice and rights,arguing that these can plausibly be seen to be grounded in theidea of autonomy and that a rights or justice based social policyand practice must be grounded in the protection, enhancementand development of the capacity for autonomous action. The articlethen presents partial findings of a research project, whichsampled social workers' views and attitudes towards direct paymentsin three local authorities. The findings suggest that socialworkers are aware of the link between direct payments and autonomyand are generally very supportive of the move to a rights basedapproach to policy and practice as evidenced by programmes suchas direct payments. The paper also concludes that structuralconstraints limit social workers' ability to fully functionfrom a rights based approach to disability.     

Biased Mentalizing in Children Aged Seven to 11: Latent Class Confirmation of Response Styles to Social Scenarios and Associations with Psychopathology

A new approach to the measurement of mentalizing is introduced. Instead of measuring the presence or absence of mentalizing capacity, the current study aimed at developing a mentalizing task that focuses on investigating biases in mentalizing through the use of ambiguous peer‐related social scenarios. The response consistency of 659 children was investigated in a community sample of children aged seven to 11. Confirmatory latent class analysis allocated children to three groups on the basis of their responses: an overly positive style (OP), a rational/neutral style (R) or an overly negative style (ON). Children classed as OP showed a greater likelihood of being above cut‐off on a population screen for externalizing disorder. Over a two‐year follow‐up period, the children who were classified as R were most likely to remain so whereas the OP and ON children were found to change group. The results are discussed in the context of social‐cognitive research in this age group. Further studies should examine the external validity of the mentalizing task because the results reported here concern only internal construct validity.     

Quasi-maximum likelihood estimation and inference in dynamic models with time-varying covariances

We study the properties of the quasi-maximum likelihood estimator (QMLE) and related test statistics in dynamic models that jointly parameterize conditional means and conditional covariances, when a normal log-likelihood os maximized but the assumption of normality is violated. Because the score of the normal log-likelihood has the martingale difference property when the forst two conditional moments are correctly specified, the QMLE is generally Consistent and has a limiting normal destribution. We provide easily computable formulas for asymptotic standard errors that are valid under nonnormality. Further, we show how robust LM tests for the adequacy of the jointly parameterized mean and variance can be computed from simple auxiliary regressions. An appealing feature of these robyst inference procedures is that only first derivatives of the conditional mean and variance functions are needed. A monte Carlo study indicates that the asymptotic results carry over to finite samples. Estimation of several AR and AR-GARCH time series models reveals that in most sotuations the robust test statistics compare favorably to the two standard (nonrobust) formulations of the Wald and IM tests. Also, for the GARCH models and the sample sizes analyzed here, the bias in the QMLE appears to be relatively small. An empirical application to stock return volatility illustrates the potential imprtance of computing robust statistics in practice.     

Moment-Based Approximations of Discrete Probability Distributions Using Rational Functions

Provost et al. (2009 Provost, S. B., Jiang, M. and Ha, H.-T. 2009. Moment-based approximations of probability mass functions with applications involving order statistics. Communications in Statistics—Theory and Methods, 38(12): 1969–1981. [Taylor & Francis Online], [Web of Science ®] , [Google Scholar]) introduced an approximation to discrete probability mass functions using a base density function and a polynomial function multiplier. In this article, we examine a new estimator constructed by using a rational function multiplier. The new approximation requires fewer moments to calculate, and generally performs better. Several example cases will be presented.     

Service Package Switching in Hotel Revenue Management Systems

Revenue Management Systems (RMS) are commonly used in the hotel industry to maximize revenues in the short term. The forecasting‐allocation module is a key tactical component of a hotel RMS. Forecasting involves estimating demand for service packages across all stayover nights in a planning horizon. A service package is a unique combination of physical room, amenities, room price, and advance purchase restrictions. Allocation involves parsing the room inventory among these service packages to maximize revenues. Previous research and existing revenue management systems assume the demand for a service package to be independent of which service packages are available for sale. We develop a new forecasting‐allocation approach that explicitly accounts for this dependence. We compare the performance of the new approach against a baseline approach using a realistic hotel RMS simulation. The baseline approach reflects previous research and existing industry practice. The new approach produces an average revenue increase of at least 16% across scenarios that reflect existing industry conditions.     

香港和深圳市铁路需求预测

亚洲的许多城市为解决城市交通问题，正关注铁路系统并允许进一步发展．对铁路系统的规划与设计必须有强有力的预测，同时对于有效路径选择效用方面的细微差别必须是敏感的．EMME／2中缺省的公交分配程序能生成出行费用矩阵，这些矩阵适用于战略模型，但是在用这个缺省的程序对铁路进行具体的预测时限制会增加．本文简述了基于logit模型的多路径公交EMME／2模型结构，它适用于低服务间隔的城市铁路网．该模型允许子模式（铁路或其他）的选择，车站和车站间路径的选择，并描述了所必需的网络编码和交通分配增加的自由选择等特征．