Satisfiability Decay along Conjunctions of Pseudo-Random Clauses

k-SAT is a fundamental constraint satisfaction problem. It involvesS(m), the satisfaction set of the conjunction of m clauses,each clause a disjunction of k literals. The problem has manytheoretical, algorithmic and practical aspects. When the clauses are chosen at random it is anticipated (butnot fully proven) that, as the density parameter m/n (n thenumber of variables) grows, the transition of S(m) to beingempty, is abrupt: It has a "sharp threshold", with probability1 – o(1). In this article we replace the random ensemble analysis by apseudo-random one: Derive the decay rule for individual sequencesof clauses, subject to combinatorial conditions, which in turnhold with probability 1 – o(1). This is carried out under the big relaxation that k is not constantbut k = log n , or even r log log n . Then the decay of S isslow, "near-perfect" (like a radioactive decay), which entailssharp thresholds for the transition-time of S below any givenlevel, down to S = .     

Principled and statistical connections in common sense conception

Nominal concepts represent things as tokens of types. We report six experiments that investigate the nature of the relations we represent between the type of thing something is (e.g. DOG) and its other properties. The experiments provide evidence that we represent principled connections between the type of thing something is (e.g. DOG) and some of its properties (k-properties; e.g. having four legs for dogs), but not other properties (t-properties; e.g. being brown for dogs). Principled connections are different from logical, statistical, and causal connections. Principled connections, (i) license the expectation that tokens of the type will generally possess the k-property, (ii) license explanation of the presence of k-properties in tokens of a type by reference to the type of thing it is, and (iii) license normative expectations concerning the presence of the k-property in tokens of the type. The experiments provide evidence for all three of these aspects of principled connections. The experiments also demonstrate that principled connections must be distinguished from merely strong statistical connections. We suggest that principled connections are one of the fundamental types of relations (in addition to logical, statistical, and causal relations) in terms of which our conceptual knowledge is structured. We argue that principled connections reveal a formal mode of understanding and explanation. This mode of understanding complements other modes of understanding that have been studied within the theory-based approach to conceptual representation. Finally, we suggest that kind representations are distinguished from representations of mere types by the representation of principled connections to k-properties.     

"Good enough stories": helping couples invest in one another's growth

This article utilizes key constructs of the narrative metaphor: that stories organize, structure, and give meaning to events in our lives. When stories are used as a way to understand the lives of couples, they have the potential for enhancing individual and relational growth. It is proposed that knowing both our own and our partner's story and development goals increases the likelihood of making an investment in self/other and relational growth. It is further suggested that helping couples develop narratives with a sense of "We" promotes a more generative perspective. These ideas were developed in a small qualitative pilot study with long-married, middle-class, heterosexual couples, which suggested that the synthesis of each partner's life story into a couple story promoted individual and relational development. Implications for therapeutic work with couples are presented as well as specific recommendations for ways to utilize the life story approach as an aspect of treatment. It is intended to assist clinicians and teachers in translating narrative ideas into therapeutic work with couples.     

Chess as a Behavioral Model for Cognitive Skill Research: Review of Blindfold Chess by Eliot Hearst and John Knott

This multifaceted work on chess played without sight of the pieces is a sophisticated psychologist's examination of this topic and of chess skill in general, including a detailed and comprehensive historical account. This review builds on Hearst and Knott's assertion that chess can provide a uniquely useful model for research on several issues in the area of cognitive skill and imagery. A key issue is the relationship between viewing a stimulus and mental imagery in the light of blindfold chess masters' consistent reports that they do not use or have images. This review also proposes a methodology for measuring and quantifying an individual's skill shortfall from a theoretical maximum. This methodology, based on a 1951 proposal by Claude Shannon, is applicable to any choice situation in which all the available choices are known. The proposed “Proficiency” measure reflects the equivalent number of “yes—no” questions that would have been required to arrive at a best choice, considering also the time consumed. As the measure provides a valid and nonarbitrary way to compare different skills and the effects of different independent variables on a given skill, it may have a wide range of applications in cognitive skill research, skill training, and education.     

Gender-related inequalities in the division of family work in close relationships: A social psychological perspective

We offer a social psychological perspective on gender-related inequalities in close relationships and integrate two lines of research that have focused on the intrapersonal perceptions and interpersonal consequences respectively of the gendered division of labour. We start with a brief summary of research on gender-related inequalities in the division of labour and discuss prior explanations and paradigms. We then address the extent to which spouses consider the division of labour as fair and the factors that contribute to perceptions of (un)fairness. Central to our argument is the distributive justice framework (<citeref rid="b76">Major, 1987</citeref>, <citeref rid="b77">1993</citeref>; <citeref rid="b113">Thompson, 1991</citeref>) which claims that fairness judgements are affected by people's wants and values, comparison standards, and justifications. In the following section, we address the question of whether dissatisfaction over the division of labour causes relationship conflict and how couples manage these conflicts. The main argument is that conflict over the division of labour generally comprises an asymmetrical conflict structure (with wives as complainants and husbands as defenders of the status quo), which elicits asymmetrical conflict interaction patterns (i.e., demand/withdraw interaction) that result in asymmetrical outcomes (i.e., status quo maintenance). Finally, we summarise the main conclusions and address contributions to theory and research as well as directions for further research.     

Evaluating the effect of educational media exposure on aggression in early childhood

Preschool-aged children (M = 42.44 months-old, SD = 8.02) participated in a short-term longitudinal study investigating the effect of educational media exposure on social development (i.e., aggression and prosocial behavior) using multiple informants and methods. As predicted, educational media exposure significantly predicted increases in both observed and teacher reported relational aggression across time. Follow-up analyses showed that educational media exposure also significantly predicted increases in parent reported relational aggression across more than a two year period. Results replicate and extend prior research that has demonstrated links between educational media exposure and relational aggression, but not physical aggression, during early childhood.     

The effect of object–valence relations on automatic evaluation

Two experiments tested the effect of co-occurrence of a target object with affective stimuli on automatic evaluation of the target when the relation between the target and the affective stimuli suggests that they have opposite valence. Participants learned about targets that ended an unpleasant noise or a pleasant music. The valence of such targets is opposite to the valence of the affective stimuli that co-occur with them. Participants reported preference for targets that ended noise over targets that ended music, but automatic evaluation measures revealed the opposite preference. This suggests that automatic evaluation is sensitive to co-occurrence between stimuli more than to the relation between the stimuli, and that relational information has a stronger influence on deliberate evaluation than on automatic evaluation. These conclusions support the associative-propositional evaluation model (Gawronski & Bodenhausen, 2006), and add evidence regarding the sensitivity of the evaluative-conditioning effect to relational information.     

Social support and cardiovascular responding to laboratory stress: Moderating effects of gender role identification,sex, and type of support

The objective of the present study was to examine moderating effects of gender role identification, sex, and type of support on the buffering role of social support on cardiovascular responses. We hypothesized that (a) gender role identification, more than sex, would moderate the effect of social support and (b) to obtain optimal attenuating effects of social support, type of support provided should match type of support preferred in terms of one's gender role identification. That is, feminine participants would benefit more from relatively direct support, whereas masculine participants would benefit more from indirect support. Healthy participants (N = 100) performed a psychological stressor in the presence of a friend, after mental activation of a friend, or alone. Results revealed no moderating effects of gender role identification whether or not in combination with type of support. Nevertheless, results demonstrated an attenuating effect of mental support on heart rate and cardiac output in men. It is concluded that pathways linking social relationships and health may differ between women and men.     

Comparison of the role of self-efficacy and illness representations in relation to dietary self-care and diabetes distress in adolescents with type 1 diabetes

This cross-sectional study examined the joint effects of self-efficacy and illness representations on dietary self-care and diabetes distress in adolescents with type 1 diabetes by comparing two theoretical models: the Self-regulation Model (Leventhal, H., Meyer, D., & Nerenz, D. (1980). The common-sense representations of illness danger. In S. Rachman (Ed.), Medical Psychology (Vol. 2, pp. 7–30). New York: Pergamon.) and Social Cognitive Theory (Bandura, A. (1997). Self efficacy: The exercise of control. New York: W.H. Freeman.). One hundred and fifty-one adolescents with type 1 diabetes completed self-report measures of dietary self-efficacy, illness representations, dietary self-care and diabetes distress. Data were analysed using structural equation modelling. The model best supported by the data (Leventhal's Self-regulation Model) showed that dietary self-efficacy, perceived consequences and treatment effectiveness had direct and independent effects on both dietary self-care and diabetes distress. Together with dietary self-efficacy, perceived short-term treatment effectiveness was a significant predictor of dietary self-care. Age was found to be a negative predictor of short-term treatment effectiveness beliefs. Diabetes distress was best predicted by self-efficacy and perceived consequences. It can be concluded that to target effectively dietary self-care and distress, clinicians should focus on key illness representation variables (perceived short-term treatment effectiveness and perceived consequences) in conjunction with self-efficacy.