Algorithms for the workflow satisfiability problem engineered for counting constraints

The workflow satisfiability problem (WSP) asks whether there exists an assignment of authorized users to the steps in a workflow specification that satisfies the constraints in the specification. The problem is NP-hard in general, but several subclasses of the problem are known to be fixed-parameter tractable (FPT) when parameterized by the number of steps in the specification. In this paper, we consider the WSP with user-independent counting constraints, a large class of constraints for which the WSP is known to be FPT. We describe an efficient implementation of an FPT algorithm for solving this subclass of the WSP and an experimental evaluation of this algorithm. The algorithm iteratively generates all equivalence classes of possible partial solutions until, whenever possible, it finds a complete solution to the problem. We also provide a reduction from a WSP instance to a pseudo-Boolean (PB) SAT instance. We apply this reduction to the instances used in our experiments and solve the resulting PB SAT problems using SAT4J, a PB SAT solver. We compare the performance of our algorithm with that of SAT4J and discuss which of the two approaches would be more effective in practice.     

Psychosocial care in nursing homes in the era of the MDS 3.0: perspectives of the experts

Meeting psychosocial needs of nursing home residents is increasingly regarded as a critical component of care, and the nationally-mandated nursing home care screening instrument- the Minimum Data Set (MDS) 3.0-was modified and implemented in 2010 to promote better assessment of psychosocial needs and health. Recognizing the importance of psychosocial well-being among nursing home residents, and the promise of MDS 3.0 for improving psychosocial care, this article reports recommendations derived from a conference of stakeholders representing diverse disciplines and organizations regarding next steps following MDS 3.0 screening. Results relate to seven areas of psychosocial care and address cross-cutting recommendations to improve psychosocial care.     

Tests for the umbrella alternative under normality

Consider a one-way layout of the analysis of variance assuming independence, normality, and homogeneity of variance. Test the null hypothesis H_o that the means, j., of each of Amp; columns, i = 1,…, k are equal versus the alternative that they follow an umbrella pattern. That is, the alternative is H₁-H₀ where H₁: μ₁> μ₂>… > μk, and m is known. We derive a class of tests which are unbiased and lie in a nontrivial complete class. We recommend specific tests within the class. A simulation of the power functions of some tests is contrasted with the simulated power function of the likelihood ratio test.     

Modified maximum likelihood and modified moment estimators for the three-parameter weibull distribution

This article is concerned with modifications of both maximum likelihood and moment estimators for parameters of the three-parameter Wei bull distribution. Modifications presented here are basically the same as those previously proposed by the authors (1980, 1981, 1982) in connection with the lognormal and the gamma distributions. Computer programs were prepared for the practical application of these estimators and an illustrative example is included. Results of a simulation study provide insight into the sampling behavior of the new estimators and include comparisons with the traditional moment and maximum likelihood estimators. For some combinations of parameter values, some of the modified estimators considered here enjoy advantages over both moment and maximum likelihood estimators with respect to bias, variance, and/or ease of calculation.     

‘I am the face of success’: peer mentors in child welfare

Child welfare systems have struggled to create innovative, culturally sensitive programmes to address the multiple and pervasive barriers that exist in engaging child welfare parent clients in their service plans. Peer mentor programmes—those in which parents who have successfully navigated the child welfare system and reunified with their children, mentor parents newly entering the system—are designed to address some of these barriers, to improve reunification outcomes. Focus groups with parent clients (n = 25) and interviews with peer mentors (n = 6) were conducted to identify the characteristics of peer mentoring programmes that are critically helpful to parent clients, as well as the mechanisms that allow peer mentors to be effective in their work. The qualitative analysis uncovered three general themes to which both parents and peer mentors frequently referred in interviews—the value of shared experiences, communication and support. Additionally, the study found that peer mentorship has positive effects not only on parent clients but also on the mentors themselves. The inclusion of peer mentors in child welfare practice suggests an important paradigm shift within child welfare that could lead to culture change for the field.     

Adaptive sequential design for regression on multi-resolution bases

This work investigates the problem of construction of designs for estimation and discrimination between competing linear models. In our framework, the unknown signal is observed with the addition of a noise and only a few evaluations of the noisy signal are available. The model selection is performed in a multi-resolution setting. In this setting, the locations of discrete sequential D and A designs are precisely constraint in a small number of explicit points. Hence, an efficient stochastic algorithm can be constructed that alternately improves the design and the model. Several numerical experiments illustrate the efficiency of our method for regression. One can also use this algorithm as a preliminary step to build response surfaces for sensitivity analysis.     

Narrative skills predict peer adjustment across elementary school years

The importance of peer adjustment in middle childhood coincides with developing social cognitive and discursive skills that include the ability to make personal narrative accounts. Authoring personal stories promotes attention to the sequence of events, the causal connections between events, the moral significance of what has happened, and the motives that drive human action: these skills may be critical for the establishment and maintenance of satisfying peer relationships during elementary school. This study extended previous research by considering whether narrative skills in written stories about peer interactions predicted peer adjustment. As part of an ongoing longitudinal study, 92 children wrote narratives about peer experiences and completed surveys on measures of peer adjustment for two school years. Cross‐lagged panel models indicated that chronological and thematic coherence and reports of moral concerns in narratives in the first year of the study contributed to lower peer disliking in the subsequent academic year. Reports of motives in Year 1 narratives contributed to lower levels of loneliness and peer victimization in Year 2. Writing personal narratives that are coherent and attentive to moral concerns and motives may be especially beneficial for children who have difficulty connecting with peers. We discuss implications for classroom practices.     

The concept of sublimation

Women's Ways of Knowing: The Development of Self, Voice and Mind. M. F. Belenky, B. M. Clinchy, N. R. Goldberger and J. M. Tarule. (New York: Basic Books, 1986.)

The Therapist's Own Family: Toward the Differentiation of Self. Peter Titelman (Ed.). (Northvale, NJ: Jason Aronson, Inc., 1987.)

Clinical Work With Adolescents. Judith Marks Mishne. (New York: The Free Press, 1986.)