Probabilities Of Causation: Three Counterfactual Interpretations And Their Identification

According to common judicial standard, judgment in favor ofplaintiff should be made if and only if it is more probable than not thatthe defendant's action was the cause for the plaintiff's damage (or death). This paper provides formal semantics, based on structural models ofcounterfactuals, for the probability that event x was a necessary orsufficient cause (or both) of another event y. The paper then explicates conditions under which the probability of necessary (or sufficient)causation can be learned from statistical data, and shows how data fromboth experimental and nonexperimental studies can be combined to yieldinformation that neither study alone can provide. Finally, we show thatnecessity and sufficiency are two independent aspects of causation, andthat both should be invoked in the construction of causal explanations for specific scenarios.     

Speech disfluencies in nonstutterers Syntactic complexity and production task effects

The differences in the number of disfluencies of 3-, 5-, and 7-year-old nonstuttering children were investigated as syntactic complexity was varied in three different syntactic constructions: 1) simple affirmative declarative with copula + ing (SAAD), 2) future (FUT), and 3) passive (PAS) within a sentence imitation and a sentence-modeling task. The subjects repeated 30 sentences from the imitation task stimuli and produced response constructions from 30 pictures from the modeling task stimuli. The 3-year-olds exhibited significantly more disfluencies than the 5-year-olds, and the 5-year-olds produced significantly more disfluencies than the 7-year-olds. All three age groups produced significantly more disfluencies on the modeling task than on the imitation task. A significant complexity effect was demonstrated for the PAS construction. Results are compared to previous research findings and discussed with reference to hypothesized linguistic complexity and task difficulty.     

Pre- and postlexical loci of contextual effects on word recognition

The context in which a word occurs could influence either the actual decoding of the word or a postrecognition judgment of the relatedness of word and context. In this research, we investigated the loci of contextual effects that occur in lexical priming, when prime and target words are related along different dimensions. Both lexical decision and naming tasks were used because previous research had suggested that they are differentially sensitive to postlexical processing. Semantic and associative priming occurred with both tasks. Other facilitative contextual effects, due to syntactic relations between words, backward associations, or changes in the proportion of related items, occurred only with the lexical decision task. The results indicate that only associative and semantic priming facilitate the decoding of a target; the other effects are postlexical. The results are related to the different demands of the naming and lexical decision tasks, and to current models of word recognition.     

Use them or lose them: Are manipulatives needed to assess numeracy and geometry performance in preschool?

In two studies, we investigated whether using three-dimensional (3D) manipulatives during assessment aided performance on a variety of preschool mathematics tasks compared to pictorial representations. On measures of children's understanding of counting and cardinality (n = 103), there was no difference in performance between manipulatives and pictures, with Bayes factors suggesting moderate evidence in favor of the null hypothesis. On a measure of children's shape identification (n = 93), there was no difference in performance between objects and pictures, with Bayes factors suggesting moderate evidence in favor of the null hypothesis. These results suggest flexibility in the materials that can be used during assessment. Pictures, or 2D renderings of 3D objects, which can be easily printed and reproduced, may be sufficient for assessing counting and shape knowledge without the need for more cumbersome concrete manipulatives.     

The “Skinny” on Body Size Requests in Personal Ads

The message that women should be thin comes from many sources; some of which may be using the terminology loosely. To test this, the Figure Rating Scale was mailed to 547 personal ad writers to examine the actual preferences of those seeking a thin partner, those seeking a physically fit partner, and those giving no weight preference. Respondents indicated ideal and acceptable body sizes for partners. The ethnicity of respondents was 85.1% White, 7.5% Hispanic, 1.4% African American, 0.7% American Indian, and 4.1% other. The mean education level was 16.6 years and the average annual income was about $40,000. Although males in the three ad categories had statistically significant differences in their choice of an ideal figure, the actual figure size differences appeared negligible, and men did not differ in the number of figures they found acceptable. Females chose the same figure as ideal despite different weight requests. The implications of males accepting a wide range of body sizes for a partner despite specifically requesting a thin one are discussed.     

The Effects of Tai Chi Chuan Relaxation and Exercise on Stress Responses and Well-Being: An Overview of Research

The rationale of this article is to review, analyze, and discuss studies concerning the role of Tai Chi in stress management and well-being, linking those studies to research on exercise, yoga, and relaxation with regard to physiological and psychological wellness. All studies reported in PsychLit and Medline between 1996 and 1999 directly related to the subject, plus other studies relevant for the analysis, are addressed in this review. Studies reviewed in this article characterize Tai Chi as a form of moderate exercise. Although Tai Chi may not be suitable for achieving aerobic fitness, it may enhance flexibility and overall psychological well-being. Cognitively, there are indications that Tai Chi exercise may lead to improvements in mood. However, it is not clear whether the positive effects of Tai Chi are due solely to its relaxation and meditation component, or whether they are the consequence of various peripheral factors, since it is known that stress reduction often occurs when we indulge in activities we find pleasurable and satisfying. An important finding is that all studies on the benefits of Tai Chi for senior adults have revealed positive results.     

Changing systems by changing individuals: the incubation approach to systems change

This article describes and evaluates the implementation of an innovative approach to systems change, the incubation approach, which was developed on a systems change project designed to increase the capacity of multiple systems (e.g., law enforcement, child protection, domestic violence, mental health, early education) to respond to children’s exposure to violence. The incubation approach encourages change agents to collaborate with project staff to gently nurture, or “incubate,” feasible and warranted change in target systems. Project staff gain concrete commitment from motivated and accessible change agents and collaborate with those agents to implement change actions. This approach works well with committed, executive-level change agents in target systems, with stable systems that have low turnover and well-integrated subsystems, and when seed funds are provided to key organizations.     

Closing the Achievement Gap: The Association of Racial Climate with Achievement and Behavioral Outcomes

This study investigated the relationship between school racial climate and students' self-reports of academic and discipline outcomes, including whether racial climate mediated and/or moderated the relationship between race and outcomes. Using the Racial Climate Survey-High School Version (M. Aber et al., unpublished), data were gathered from African American (n = 382) and European American students (n = 1456) regarding their perceptions of racial climate. About 18% of the respondents were low-income and approximately 50% were male. Positive perceptions of the racial climate were associated with higher student achievement and fewer discipline problems. Further, race moderated the relationship between racial climate and both achievement and discipline outcomes. Finally, racial differences in students' grades and discipline outcomes were associated with differences in perceptions of racial climate. Results suggest careful attention should be given to the racial climate of secondary schools, particularly for adolescents who perceive schools as unfair.     

Falsely recalled items are rich in item-specific information

Current theorizing suggests that critical lures in the Deese/Roediger-McDermott (DRM) procedure are often falsely remembered because they have received considerable relational processing (e.g., spreading activation or encoding of gist information). We used a repeated-testing paradigm to assess the amount of item-specific and relational processing given to the list items and the critical lures. Research has shown that items receiving item-specific processing are more likely to be recovered across successive tests. They are also output more slowly but more steadily throughout the recall period. In two experiments, we manipulated the processing performed on list items and then used item gains and cumulative recall curves to assess the amount of item-specific an drelational information encoded for both list items and lures. The results suggest that increasing the relational processing of list items increased item-specific processing of lures, whereas increasing item-specific processing of list items decreased item-specific processing of lures. We conclude that critical lures are typically rich in item-specific information, relative to list items.     

Comparing mathematics interventions: Does initial level of fluency predict intervention effectiveness?

A paucity of research has directly compared empirically supported interventions to examine their effectiveness among students with different mathematics fluency skills. The purpose of this study was to compare the effects of two empirically supported interventions and a control condition on the mathematics fluency of 98 second and third grade students. Specifically, effects of explicit timing and cover-copy-compare on subtraction fluency were examined each session, which occurred twice weekly for a total of six weeks. HLM was used to examine progress during the intervention sessions and determine the effect of initial fluency level on intervention effectiveness. Results suggested students' initial level of fluency impacted intervention effectiveness. That is, for students whose fluency levels fell within the frustrational range CCC and control conditions resulted in the best performance over time but for children whose fluency was in the instructional range explicit timing was the most effective treatment.