Mathematical programming: Turing completeness and applications to software analysis

Mathematical programming is Turing complete, and can be used as a general-purpose declarative language. We present a new constructive proof of this fact, and showcase its usefulness by discussing an application to finding the hardest input of any given program running on a Minsky Register Machine. We also discuss an application of mathematical programming to software verification obtained by relaxing one of the properties of Turing complete languages.     

Short-Term GDP Forecasting With a Mixed-Frequency Dynamic Factor Model With Stochastic Volatility

In this article, we develop a mixed frequency dynamic factor model in which the disturbances of both the latent common factor and of the idiosyncratic components have time-varying stochastic volatilities. We use the model to investigate business cycle dynamics in the euro area and present three sets of empirical results. First, we evaluate the impact of macroeconomic releases on point and density forecast accuracy and on the width of forecast intervals. Second, we show how our setup allows to make a probabilistic assessment of the contribution of releases to forecast revisions. Third, we examine point and density out of sample forecast accuracy. We find that introducing stochastic volatility in the model contributes to an improvement in both point and density forecast accuracy. Supplementary materials for this article are available online.     

A Probabilistic Dealing Strategy

A probabilistic dealing strategy is proposed which allows all premium brands in an established market to earn nonnegative profits without cooperation. Following the strategy, brands take turns attracting deal-responsive customers. Relative to a reactive competitive strategy, the proposed strategy improves the positions of all premium brands. With use of the strategy, average deal sizes are positively related to a brand's market share, the proportion of quality conscious customers, the proportion of informed customers, the span of regular prices in a market, and the range of customers' acceptable prices.     

A comparison of recent nonparametric methods for testing effects in two-by-two factorial designs

The two-way two-levels crossed factorial design is a commonly used design by practitioners at the exploratory phase of industrial experiments. The F-test in the usual linear model for analysis of variance (ANOVA) is a key instrument to assess the impact of each factor and of their interactions on the response variable. However, if assumptions such as normal distribution and homoscedasticity of errors are violated, the conventional wisdom is to resort to nonparametric tests. Nonparametric methods, rank-based as well as permutation, have been a subject of recent investigations to make them effective in testing the hypotheses of interest and to improve their performance in small sample situations. In this study, we assess the performances of some nonparametric methods and, more importantly, we compare their powers. Specifically, we examine three permutation methods (Constrained Synchronized Permutations, Unconstrained Synchronized Permutations and Wald-Type Permutation Test), a rank-based method (Aligned Rank Transform) and a parametric method (ANOVA-Type Test). In the simulations, we generate datasets with different configurations of distribution of errors, variance, factor's effect and number of replicates. The objective is to elicit practical advice and guides to practitioners regarding the sensitivity of the tests in the various configurations, the conditions under which some tests cannot be used, the tradeoff between power and type I error, and the bias of the power on one main factor analysis due to the presence of effect of the other factor. A dataset from an industrial engineering experiment for thermoformed packaging production is used to illustrate the application of the various methods of analysis, taking into account the power of the test suggested by the objective of the experiment.     

The impact of the European Youth Guarantee on active labour market policies: A convergence analysis

The European Union’s (EU) Youth Guarantee aims to improve the labour market situation of young people. Rather than prescribing a uniform policy model, it acknowledges that supportive measures need to align with national, regional and local circumstances. It thus seeks to promote mutual policy learning through the open method of coordination. As an innovative measure, the EU has deployed funding programmes to support the domestic measures related to the Youth Guarantee. We therefore examined in this study whether this mix of recommendations and financial incentives has entailed a convergence of member state policies. Our analysis of policy outputs for the period 2007?2014 yields a mixed empirical picture. There is catching‐up convergence regarding policies’ sectoral coverage but increasing divergence concerning the number of adopted policy instruments. The first two years of financial incentives did not produce any effect on enhancing policy experimentation among less active member states. We offer an optimistic and a pessimistic interpretation of these findings.     

Bridging the work-family policy and productivity gap: A literature review

This paper uses both qualitative and quantitative methods to examine the relationship between work-family conflict and six work outcomes: performance, turnover, absenteeism, organizational commitment, job involvement, and burnout. Also reviewed are studies on the effects of employer (work-family) policies aimed at reducing such conflict. Policies to aid employees in managing work and family roles can be expensive, and studies show that they are often marginally effective. The review shows that relationships between work-family policies and organizational effectiveness is mixed and their connection to work-family conflict often under-examined. Work-family conflict is a critical link that may shed light on policy impacts. Suggestions on how future studies can build bridges between practitioners and academics and more clearly examine organizational effectiveness links are provided.     

Do Associations Between Pleasure Ratings and Condom Use During Penile–Vaginal Intercourse Vary by Relationship Type?: A Study of Canadian University Students

Research suggests the relationship between pleasure and condom use during penile–vaginal intercourse (PVI) is associated with relationship status. This online study examined pleasure ratings and condom use at last PVI, stratifying by partner type, among a national sample of Canadian university students. Participants were 715 undergraduates (60.7% women, 39.3% men) who reported on their most recent sexual experience. Condom use decreased with level of relationship commitment, whereas ratings of pleasure increased. Overall, participants were more likely to rate their most recent PVI as Very pleasurable when condoms were not used compared to when condoms were used. However, when stratified by partner type, these differences largely disappeared. For women, with one exception, there were no differences in pleasure between PVI with and without condoms across most partner-type categories. Women in committed dating relationships were more likely to report their last PVI as very pleasurable if condoms were not used than women in these same relationships who had used condoms. Across relationship categories, men who did and did not use condoms did not differ in terms of their pleasure ratings. The results of this study suggest relationship context should be taken into account when assessing condom use experiences.     

Infusing Clinical Supervision Throughout Child Welfare Practice: Advancing Effective Implementation of Family-Centered Practice Through Supervisory Processes

Child welfare supervision is fundamental to advancing the quality of practice when seeking to ensure the safety, permanency, and well-being of children. Child welfare supervisors serve administrative, educational, and support functions as they oversee frontline caseworkers and direct service providers. Clinical supervision, a dialog-driven process of case review and consultation is situated within the educational function. The process of clinical supervision is essential to child welfare practice, because it prompts reflection and builds analytical thinking skills needed to address complex situations involved in child protection. Despite increased recognition regarding the importance of clinical supervision, child welfare supervision continues to focus primarily on administrative tasks. Organizational climate and external pressures push this administrative agenda. In addition, many child welfare supervisors lack experience, training, and therefore competency in facilitating clinical case reviews. Strengths-Based Supervision (SBS; Lietz 2013) is a model of clinical supervision that was developed to (a) increase child welfare supervisors’ intentionality regarding the importance of infusing clinical supervision into child welfare supervision and (b) advance the skills needed to implement this practice effectively representing one solution to this ongoing challenge.     

The Influence of Career Planning on Career Thoughts in STEM‐Interested Undergraduates

Undergraduate career planning courses have shown efficacy in decreasing students’ negative career thoughts; however, universities have minimally applied these courses to science, technology, engineering, and math (STEM) populations. This study compared the influence of a STEM‐focused career planning course for undecided STEM students with a seminar course for decided STEM majors. An analysis of covariance with covariate adjustment revealed that undecided career planning students had lower adjusted mean scores on a measure of negative career thinking than the decided STEM majors after the first semester of college. The results provide support for the efficacy of STEM‐focused career planning courses and measuring negative career thoughts with STEM undergraduates.     

Contrasting perspectives of parents and service providers on respite care in Queensland,Australia

Abstract

Parent-carers need support to continue to care for their child with significant disability in their home. There has, however, been little evidence that respite interventions have consistent or enduring beneficial effects on carer well-being. This article reports the findings of a qualitative study which adopted an Appreciative Inquiry philosophy to interview parent-carers of children with significant intellectual and/or developmental disabilities on how formal support services have helped them maintain their health and well-being, and disability support staff on how they help such parent-carers foster their health and well-being. We conclude that better communication and collaboration between service providers and users, more targeted training of workers, and embracing a person-centred and family-centred approach to respite services are needed. In addition, clearer definition and communication of the scope of respite services are required to best support families of children with significant disability in their home.