Evaluating surrogate variables for improving microarray multiple testing inference

The use of surrogate variables has been proposed as a means to capture, for a given observed set of data, sources driving the dependency structure among high-dimensional sets of features and remove the effects of those sources and their potential negative impact on simultaneous inference. In this article we illustrate the potential effects of latent variables on testing dependence and the resulting impact on multiple inference, we briefly review the method of surrogate variable analysis proposed by Leek and Storey (PNAS 2008; 105:18718-18723), and assess that method via simulations intended to mimic the complexity of feature dependence observed in real-world microarray data. The method is also assessed via application to a recent Merck microarray data set. Both simulation and case study results indicate that surrogate variable analysis can offer a viable strategy for tackling the multiple testing dependence problem when the features follow a potentially complex correlation structure, yielding improvements in the variability of false positive rates and increases in power.     

Statistical approaches for conducting network meta-analysis in drug development

We introduce health technology assessment and evidence synthesis briefly, and then concentrate on the statistical approaches used for conducting network meta-analysis (NMA) in the development and approval of new health technologies. NMA is an extension of standard meta-analysis where indirect as well as direct information is combined and can be seen as similar to the analysis of incomplete-block designs. We illustrate it with an example involving three treatments, using fixed-effects and random-effects models, and using frequentist and Bayesian approaches. As most statisticians in the pharmaceutical industry are familiar with SAS? software for analyzing clinical trials, we provide example code for each of the methods we illustrate. One issue that has been overlooked in the literature is the choice of constraints applied to random effects, and we show how this affects the estimates and standard errors and propose a symmetric set of constraints that is equivalent to most current practice. Finally, we discuss the role of statisticians in planning and carrying out NMAs and the strategy for dealing with important issues such as heterogeneity.     

Designing Lateral Organizations: An Analysis of the Benefits,Costs, and Enablers of Nonhierarchical Organizational Forms*

Twenty-first century organizations will require designs that enable them to cope with turbulent environments. Organizations have experimented with lateral organizational designs for this purpose, but research evidence concerning these forms is sparse. We analyzed data obtained from 512 employees within eight diverse organizations implementing flexible lateral organizations. Using a sequence comparison methodology, we were able to identify and categorize the major costs, benefits, and enablers associated with implementing these forms of complex organizations. Propositions for effectively managing lateral relations were tested and managerial implications were explored.     

Integration Between Business Planning and Information Systems Planning: Validating a Stage Hypothesis

This paper proposes and empirically validates a stages of growth model for the evolution of Information Systems Planning (ISP). A questionnaire survey of senior IS executives is used to gather information pertaining to the stages of growth model, which includes measurement of the nature and level of integration between business planning (BP) and ISP. The del test is used to validate empirically benchmark variables for each stage of BP-ISP integration. The results support the stages of growth model of BP-ISP integration and the benchmark variables are generally found to be successful in predicting the stage of integration.     

Early intervention and holistic,relationship‐based practice with fathers: evidence from the work of the Family Nurse Partnership

This paper seeks to add to the literature on working with fathers by focusing on early intervention. It draws on research into fathers involved in a home visitation service delivered by the Family Nurse Partnership in England and evaluates the men's experiences of the intervention. The vulnerability of fathers was striking and many were helped to develop their practical skills and confidence in caring for their babies. The intervention was effective because of the quality time that was invested in developing relationships with fathers (as well as mothers), the focus on their strengths as well as areas for improvement and the skilled, therapeutically oriented, holistic approach through which the service was delivered. The ‘early’ nature of the help was crucial to its success because of how it so effectively tapped into the men's redefinition of themselves as caring fathers during pregnancy and following the birth. We argue that there is important learning here for social care and health services in general about how to engage men and promote fathers' capacities to care for their children.     

Social inclusion,exclusion, and well‐being in Australia: meaning and measurement

This paper begins by examining the social inclusion agenda that formed the centrepiece of the social policy agenda of the Australian Government between 2007 and 2013. It discusses several features of the agenda, including its objectives (as articulated by the government) and some of the administrative and bureaucratic mechanisms that were put in place to assist with its development and implementation. Although no formal assessment of the impact of the agenda is attempted, some of the ways in which such an agenda could make a difference are identified. The paper then summarises the social inclusion indicator framework developed by the Australian Social Inclusion Unit with assistance and advice from the Australian Social Inclusion Board, and compares its structure and content with the frameworks developed by two of Australia's leading social research institutes. Finally, data from two national surveys of poverty and social exclusion are used to examine recent changes in social exclusion and the association between the severity of exclusion and levels of subjective well‐being. These latter results show clearly that subjective well‐being is consistently lower among those who experience the greatest degree of social exclusion, suggesting that exclusion as identified and measured reflects external constraints rather than internal preferences.     

Deprivation and Poverty in Hong Kong

Despite high and rising real incomes, the poverty rate in Hong Kong remains a cause of community concern. The government has been reluctant to set a poverty line, although the recently (re‐)established Commission on Poverty has recommended that a poverty line for Hong Kong is developed. Against this background, this article reports results derived from a new deprivation study designed to shed new light on the living standards of the poorest in the community. Reflecting international studies, deprivation is identified as existing when people do not have and cannot afford items regarded by a majority in the community as being essential for all. A list of 35 basic needs items is identified as meeting this definition, the results indicating that around 30 per cent are deprived of at least two items, over 18 per cent are deprived of at least four items and 10 per cent are deprived of at least eight items. Deprivation rates are particularly high among items that meet basic health needs. A mean deprivation score index (MDIS) is then used to compare the degree of deprivation experienced by different groups, and indicates that deprivation is most pronounced amongst those receiving Comprehensive Social Security Assistance (CSSA), people affected by a disability and recent migrants. The overlap between deprivation and income poverty is also relatively low, which suggests both measures have a role to play in identifying who is most vulnerable and guiding where policy change is most urgently needed.     

Addressing common forms of child maltreatment: evidence‐informed interventions and gaps in current knowledge

This paper reviews interventions for preventing the occurrence and recurrence of major types of child maltreatment. We begin with an overview of the challenges of establishing evidence‐based interventions to prevent child abuse and neglect in many countries, and underscore the importance of this need with child maltreatment incidence rates in the USA, and how much each type and subtype contribute to child out‐of‐home placement. Next, we identify the well‐supported, supported and promising interventions for each child maltreatment type and subtype, according to their level of research evidence using an evidence‐based clearing house. The paper closes with a discussion of the implications for practice, evaluation, policy and agency management, including intervention knowledge gaps that showcase areas that need additional practice research.     

From Amazon to Apple: Modeling Online Retail Sales,Purchase Incidence,and Visit Behavior

In this study, we propose a multivariate stochastic model for Web site visit duration, page views, purchase incidence, and the sale amount for online retailers. The model is constructed by composition from carefully selected distributions and involves copula components. It allows for the strong nonlinear relationships between the sales and visit variables to be explored in detail, and can be used to construct sales predictions. The model is readily estimated using maximum likelihood, making it an attractive choice in practice given the large sample sizes that are commonplace in online retail studies. We examine a number of top-ranked U.S. online retailers, and find that the visit duration and the number of pages viewed are both related to sales, but in very different ways for different products. Using Bayesian methodology, we show how the model can be extended to a finite mixture model to account for consumer heterogeneity via latent household segmentation. The model can also be adjusted to accommodate a more accurate analysis of online retailers like apple.com that sell products at a very limited number of price points. In a validation study across a range of different Web sites, we find that the purchase incidence and sales amount are both forecast more accurately using our model, when compared to regression, probit regression, a popular data-mining method, and a survival model employed previously in an online retail study. Supplementary materials for this article are available online.     

Exploring the association between board and organizational performance in nonprofit organizations

Note: This study investigated six dimensions of effective board performance, as suggested by Chait, Holland, and Taylor (1991), in relation to three theoretical explanations (agency theory, resource dependency theory, and group/decision process theory) of how board governance activities potentially influence organizational performance. Survey research findings revealed that strategic contributions from the board are more robust in organizations with higher financial performance. In addition, organizations that are judged to be higher performing also reported having high‐performing boards across all dimensions. In particular, the interpersonal dimension provided a unique explanation of judgments of organizational performance.