图片信息丰裕度对消费者在线风险决策的影响

以图片标记信息丰裕度对消费者在线风险决策的影响为研究重点,引入详尽可能性模型(ELM),从购买行为发生之前的顾客关注度和购买之后的顾客满意度两个纬度,探索了消费者在线风险决策的影响因素。结果表明:信誉标记图片信息丰裕度中的评价方式种类和商家信用度、服务标记图片信息丰裕度中的保障服务以及商品促销标记,无论对消费者关注度还是消费者满意度均有显著的正向影响;支付服务图片信息丰裕度对消费者关注度影响不显著,但与消费者满意度有显著的正相关关系。另外,店铺动态评分、物流服务标记以及商品描述标记的图片信息丰裕度与消费者关注度及满意度相关性均不显著。研究结果为C2C交易平台以及网上卖家图片标记和信息展示提供了一定的理论指导。     

基于贝叶斯SDM模型的中国城镇居民收入收敛性分析

随着中国经济的高速增长,中国区域间贫富差距也日渐加大,在此背景下对中国城镇居民收入是否收敛进行检验并探究其影响原因十分必要。基于一个包括物质资本和人力资本投入的新古典增长模型,根据中国31个省市的1987—2013年数据,利用SDM模型和贝叶斯MCMC统计分析方法,研究城镇居民收入的收敛性问题,结果发现:中国城镇居民人均收入具有显著的空间差异,且在1987—2008年为发散、在2008—2013年以及1987—2013年为存在β收敛的变化趋势;物质资本对中国城镇居民收入增长的β收敛具有正向促进作用,而人力资本对其具有反向促进作用,增加物质资本投入有利于缩小地区收入差距,二者的不匹配可能是导致中国收入增长差距的原因。     

牧地承包经营权转让意愿影响因素研究——基于农户劳动力配置视角

基于西部3省731户农(牧)户的实地调研数据,从农(牧)户劳动力配置视角分析了牧地承包经营权转让意愿的影响因素。研究结果表明:务牧人口数、近三年务牧消耗、务牧技能水平等对牧地承包经营权转出意愿有显著的负向影响;务工兼牧业人口数、务工技能水平和户均单位土地劳动投入对牧地承包经营权转出意愿有显著的正向影响;务工人口数、户主受教育程度等对牧地承包经营权转让意愿的影响不显著。     

Testing for bioequivalence of highly variable drugs from TR‐RT crossover designs with heterogeneous residual variances

Traditional bioavailability studies assess average bioequivalence (ABE) between the test (T) and reference (R) products under the crossover design with TR and RT sequences. With highly variable (HV) drugs whose intrasubject coefficient of variation in pharmacokinetic measures is 30% or greater, assertion of ABE becomes difficult due to the large sample sizes needed to achieve adequate power. In 2011, the FDA adopted a more relaxed, yet complex, ABE criterion and supplied a procedure to assess this criterion exclusively under TRR‐RTR‐RRT and TRTR‐RTRT designs. However, designs with more than 2 periods are not always feasible. This present work investigates how to evaluate HV drugs under TR‐RT designs. A mixed model with heterogeneous residual variances is used to fit data from TR‐RT designs. Under the assumption of zero subject‐by‐formulation interaction, this basic model is comparable to the FDA‐recommended model for TRR‐RTR‐RRT and TRTR‐RTRT designs, suggesting the conceptual plausibility of our approach. To overcome the distributional dependency among summary statistics of model parameters, we develop statistical tests via the generalized pivotal quantity (GPQ). A real‐world data example is given to illustrate the utility of the resulting procedures. Our simulation study identifies a GPQ‐based testing procedure that evaluates HV drugs under practical TR‐RT designs with desirable type I error rate and reasonable power. In comparison to the FDA's approach, this GPQ‐based procedure gives similar performance when the product's intersubject standard deviation is low (≤0.4) and is most useful when practical considerations restrict the crossover design to 2 periods.     

A simulation study of methods for selecting subgroup‐specific doses in phase 1 trials

Patient heterogeneity may complicate dose‐finding in phase 1 clinical trials if the dose‐toxicity curves differ between subgroups. Conducting separate trials within subgroups may lead to infeasibly small sample sizes in subgroups having low prevalence. Alternatively,it is not obvious how to conduct a single trial while accounting for heterogeneity. To address this problem,we consider a generalization of the continual reassessment method on the basis of a hierarchical Bayesian dose‐toxicity model that borrows strength between subgroups under the assumption that the subgroups are exchangeable. We evaluate a design using this model that includes subgroup‐specific dose selection and safety rules. A simulation study is presented that includes comparison of this method to 3 alternative approaches,on the basis of nonhierarchical models,that make different types of assumptions about within‐subgroup dose‐toxicity curves. The simulations show that the hierarchical model‐based method is recommended in settings where the dose‐toxicity curves are exchangeable between subgroups. We present practical guidelines for application and provide computer programs for trial simulation and conduct.     

Alone and adrift: The association between mass school shootings,school size,and student support

Background

School shootings have approached epidemic levels in recent years. While mental illness is undoubtedly involved in nearly all cases of mass school violence, we sought to determine how environmental context may exacerbate preexisting personal factors. The present study investigated the associations between mass school shootings, school enrollment size, student–teacher ratios, and student transitions.

Trajectory of problem behaviours of Korean adopted children: using piecewise hierarchical linear growth modelling

This study examined the trajectory of problem behaviours in domestically adopted children in South Korea as they aged. This study used the Panel Study on Korean Adopted Children's longitudinal, three‐wave data (2006, 2008 and 2010). Although data were collected at three time points, our data consisted of six time points, which covered the 5–10 years age range of the adopted children at the time of survey. One hundred sixty‐four children were included in the analysis, 75 of whom contributed to one time point, 74 to two time points and 15 to three time points. The trajectory of the problem behaviours of adopted children was examined using a piecewise hierarchical linear growth model. Because the initial exploration of the data suggested non‐linear changes in behaviour problems over time, we split the growth trajectory into two time periods: Time 1 (5–7 years) and Time 2 (7–10 years). A two‐rate model was used to estimate separate slopes for the two time periods. Results showed that the externalizing and internalizing problems of adopted children have different trajectories. Internalizing problems did not show significant changes after 5 years of age, while externalizing problems increased until 7 years of age and decreased significantly thereafter.     

Rethinking the Individualized Education Plan process: voices from the other side of the table

Parent involvement in the process of creating an Individualized Education Plan (IEP) is authorized under the Individuals with Disabilities Education Act, a federal law in the United States that ensures children with disabilities have the opportunity to receive a free appropriate public education alongside their peers without disabilities in the least restrictive environment. Yet much research has shown that parents often feel like outsiders during the process. To understand parent perspectives about how educators might help make the IEP process more collaborative and inclusive, this study collected qualitative data from 35 parents of students with disabilities who have worked to develop an IEP with a school team. Our findings provide insight into parent experiences and evidence that parents have many suggestions for how educators can improve the IEP process. In our discussion section, we provide educators with strategies to address parent suggestions.     

Exploring how the social model of disability can be re-invigorated: in response to Mike Oliver

In his 2013 article in Disability & Society, Oliver recommended that the social model should either be replaced or re-invigorated. I argue here that the social model’s current emphasis reflects the social conditions in which it was introduced, and that the model’s impact on disabled people’s lives would increase if its emphasis was to more accurately reflect the current social conditions in the geographical regions in which it is applied. In order to help foster its re-invigoration, I ask five questions for discussion on the way forward for the social model. I identified my questions through examining published writing on the scope of the social model and on the model’s relationship with other models of disability.     

Developing a model of disability that focuses on the actions of disabled people

Disabled people, writers on disability and disability activists stress the importance of disabled people being included in all aspects of society. I argue that a major omission from this inclusiveness is that no current model of disability focuses on the impact of the actions of disabled people on disability. Disabled people are not passive bystanders, powerless to reduce the restrictions of disability. On the contrary, we are central to actively limiting its constraints. I develop a model of disability, called ‘active’, which focuses on the effects on disability of the individual and collective actions of disabled people. I describe published findings which indicate that engaging in self-help, using support groups and deploying assistive technology can all reduce the limitations of disability. Recent increases in the number of disability support groups and developments in assistive technology have substantially augmented the potential for disabled people to combat the effects of disability.