A multivariate analysis of an experimental design involving a complete set of latin squares

A model for an experimental design involving a complete set of Latin squares for testing the homogeneity of treatment effects was constructed and analyzed by Gourlay. In his analysis, however, if one or both of the preliminaryF-tests are significant, the analysis cannot differentiate. He then suggests the use of a less desirable test which is biased and has fewer degrees of freedom, regardless of the number of replications (the d.f. cannot be increased by increasing the replications). Further, when heterogeneity of variance occurs, Gourlay's test procedures are in general invalid. The present paper reviews Gourlay's analysis and proposes a modified test procedure.My thanks are due to Drs. R. S. Hirsch, R. L. Erdmann, and R. M. Simons of IBM Corporation for many stimulating discussions, and to Professor D. Teichroew of Stanford University for permission to refer to his paper [6] and his assistance. I also wish to thank B. A. Snyder for correcting many linguistic mistakes.     

Between-individual comparisons in performance evaluation: a perspective from prospect theory

This article examines how between-individual comparisons influence performance evaluations in rating tasks. The authors demonstrated a systematic change in the perceived difference across ratees as a result of changing the way performance information is expressed. Study 1 found that perceived performance difference between 2 individuals was greater when their objective performance levels were presented with small numbers (e.g., absence rates of 2% vs. 5%) than when they were presented with large numbers (e.g., attendance rates of 98% vs. 95%). Extending this finding to situations involving trade-offs between multiple performance attributes across ratees, Study 2 showed that the relative preference for 1 ratee over another actually reversed when the presentation format of the performance information changed. The authors draw upon prospect theory to offer a theoretical framework describing the between-individual comparison aspect of performance evaluation.     

Characteristics of suicide attempters and nonattempters with schizophrenia in a rural community

In this study, demographic and clinical characteristics of individuals with schizophrenia in a Chinese rural community who had attempted suicide at some time in their lives and those who had not made a suicide attempt were compared. Among individuals with schizophrenia, subjects with (n = 38) and without (n = 472) a lifetime history of suicide attempt were assessed with the Present State Examination. The results indicate that attempters had a significantly younger age, higher level of education, higher rate of lifetime depressed mood and hopelessness, and a larger number of positive symptoms than patients without suicide attempts. The logistic regression models also indicated that hopelessness, the number of positive symptoms and age were the most important predictors. Early interventions focusing on reducing hopelessness and controlling positive symptoms may help reduce the risk of suicide attempts among patients with schizophrenia.     

Visual analogue scale correlates of musculoskeletal fatigue

Visual analogue scale has been shown to reflect subjective feelings but rarely has it been used for musculoskeletal fatigue so in the present study VAS ratings were used to quantify musculoskeletal fatigue. A total of 20 students underwent a fatigue protocol (M age=21.3 yr., SD= 1.0). A series of randomized external loads at 0, 5, 10, 15, 25, 35, and 50% of the maximum voluntary contraction was generated by the BTE Primus and applied at the distal end of the dominant arm, which was sustained at the 90 degrees forward flexion position. After 60 sec. of force exertion for each loading, the subject marked the scale to reflect their extent of fatigue at the shoulder muscle. Analysis showed fatigue scores were significantly correlated with the percentages of maximum load applied (r =.73, p < or = .01). The correlation between higher external loads (25-50% maximum load) and fatigue scores was .57 (p < or = .01) and that for lower external loads (0-15% maximum load) was .44 (p < or = .01). The validity of using a visual analogue scale as a measure of musculoskeletal fatigue requires further study, particularly for a low load.     

Suicidal behavior among inpatients with schizophrenia and mood disorders in Chengdu, China

This study evaluated the characteristics of suicidal behavior (suicide attempt or suicidal ideation) among 230 consecutively admitted inpatients with schizophrenia and mood disorders in a university hospital in China. The rate of lifetime suicidal behavior was found to be significantly higher in patients with mood disorders (62.4%) than in patients with schizophrenia (38.6%). The rate of suicidal behavior was significantly higher in patients with major depressive disorder (86.8%) than those with bipolar disorders (42.6%). Patients with schizophrenia attempted suicide for the first time earlier in life than the patients with mood disorders. Mood disorder patients, especially those with major depressive disorder, had more and more serious suicide attempts than the patients with schizophrenia.     

Two- and three-year-olds infer and reason about design intentions in order to categorize broken objects

In naming artifacts, do young children infer and reason about the intended functions of the objects? Participants between the ages of 2 and 4 years were shown two kinds of objects derived from familiar categories. One kind was damaged so as to undermine its usual function. The other kind was also dysfunctional, but made so by adding features that appeared to be intentional. Evidence that 2‐, 3‐ and 4‐year‐olds were more likely to apprehend the broken objects than the intentionally dysfunctional objects as members of the familiar lexical categories favors the conclusion that, in naming, children may spontaneously infer and reason about design intentions from an early age. This is the first evidence that 2‐ and 3‐year‐olds not only take design intentions into account in object categorization, but that they do so even without explicit mention of the objects’ accidental or intentional histories. The results cast doubt on a proposal that young children's lexical categorization is based on automatic, non‐deliberative processes.     

Children's understanding of television advertising: a revisit in the Chinese context

The authors conducted a survey of 1,758 elementary school children (6-14 years old) from December 2001, to March 2002, in 3 Chinese cities with different levels of television advertising. The authors used D. R. John's (1999) model of consumer socialization as the theoretical framework for their study. More than half of the children whom the authors interviewed were able to understand that television stations broadcast commercials to earn money. Their understanding of the purposes of television commercials and the persuasive intention of television commercials developed with age. The authors examined the influence of gender, level of advertising, and level of television viewing on children's understanding of television advertising by using 3-way factorial models.     

How are social identities linked to self-conception and intergroup orientation? The moderating effect of implicit theories

Social identity approaches assume that social identification affects both self-conception and intergroup orientation. The authors contend that such social identification effects are accentuated when people hold a fixed view of human character and attribute immutable dispositions to social groups. To these individuals, social identities are immutable, concrete entities capable of guiding self-conception and intergroup orientation. Social identification effects are attenuated when people hold a malleable view of human character and thus do not view social identities as fixed, concrete entities. The authors tested and found support for this contention in three studies that were conducted in the context of the Hong Kong 1997 political transition, and discussed the findings in terms of their implications for self-conceptions and the meaning of social identification.     

Phonological processing in reading Chinese among normally achieving and poor readers

Ninety-four children in grades one to six (7 to 12 years old) in Hong Kong were individually administered a Chinese reading test consisting of 80 characters that varied in frequency (high or low) and orthographic structure (simple or complex). Phonological processing tasks, including short-term memory, pseudo-character recognition, and tone discrimination, were also administered. During reading, younger normal and poor readers made more semantic and visual errors, whereas older and normally achieving children made more phonologically related errors. Normally achieving readers also performed at a higher level than poor readers on short-term memory, pseudo-character recognition, and tone discrimination tasks. Phonological processing apparently plays a significant part in the development of reading skills in Chinese.