情绪代理变量对投资者决策的影响

情绪代理变量是指影响投资者对市场判断的非经济变量,主要包括天气、人体生物钟、月运周期、信念、社会事件、资本形象等。与蝴蝶效应类似,其影响在现实中往往被忽略了,但研究表明它们却会使股票市场出现巨大的波动。文章总结了两类情绪代理变量（“错误归因”情绪变量和“启发式”情绪变量）对投资者决策产生影响的研究,这些研究结果可以使投资者从认识自己的情绪中获益,也可为我国决策层和监管层制定出合理的政策提供依据     

Solution Strategies and Achievement in Dutch Complex Arithmetic: Latent Variable Modeling of Change

In the Netherlands, national assessments at the end of primary school (Grade 6) show a decline of achievement on problems of complex or written arithmetic over the last two decades. The present study aims at contributing to an explanation of the large achievement decrease on complex division, by investigating the strategies students used in solving the division problems in the two most recent assessments carried out in 1997 and in 2004. The students’ strategies were classified into four categories. A data set resulted with two types of repeated observations within students: the nominal strategies and the dichotomous achievement scores (correct/incorrect) on the items administered.It is argued that latent variable modeling methodology is appropriate to analyze these data. First, latent class analyses with year of assessment as a covariate were carried out on the multivariate nominal strategy variables. Results showed a shift from application of the traditional long division algorithm in 1997, to the less accurate strategy of stating an answer without writing down any notes or calculations in 2004, especially for boys. Second, explanatory IRT analyses showed that the three main strategies were significantly less accurate in 2004 than they were in 1997.     

What Carries a Mediation Process? Configural Analysis of Mediation

Mediation is a process that links a predictor and a criterion via a mediator variable. Mediation can be full or partial. This well-established definition operates at the level of variables even if they are categorical. In this article, two new approaches to the analysis of mediation are proposed. Both of these approaches focus on the analysis of categorical variables. The first involves mediation analysis at the level of configurations instead of variables. Thus, mediation can be incorporated into the arsenal of methods of analysis for person-oriented research. Second, it is proposed that Configural Frequency Analysis (CFA) can be used for both exploration and confirmation of mediation relationships among categorical variables. The implications of using CFA are first that mediation hypotheses can be tested at the level of individual configurations instead of variables. Second, this approach leaves the door open for different types of mediation processes to exist within the same set. Using a data example, it is illustrated that aggregate-level analysis can overlook mediation processes that operate at the level of individual configurations.     

Ready or not? Stages of change as predictors of brief group therapy outcome in bulimia nervosa

Although group therapy is often recommended for the treatment of bulimia nervosa, relatively little is known about predictors of short-term outcome. This pilot study examined whether a standardized measure of readiness for change might be related to changes in binge frequency. Sixteen bulimic patients participated in short-term cognitive behavioral group therapy for twelve weeks. Each patient completed the Change Assessment Scale prior to treatment, along with a battery of symptom measures which were readministered at the conclusion of therapy. Bulimic patients with positive outcome in binge frequency were at a higher stage of readiness for change at pretreatment than were patients with negative outcome. Results indicated that there may be methods of determining who would be most likely to benefit from cognitive behavioral group therapy, and tentatively suggest that interventions may be more successful when readiness for change is taken into consideration.     

Items bundles

An item bundle is a small group of multiple choice items that share a common reading passage or graph, or a small group of matching items that share distractors. Item bundles are easily identified by paging through a copy of a test. Bundled items may violate the latent conditional independence assumption of unidimensional item response theory (IRT), but such a violation would not typically suggest the existence of a new fundamental human ability to read one specific reading passage or to interpret one specific graph. It is important, therefore, to have theoretical concepts and empirical checks that distinguish between, on the one hand, anticipated violations of latent conditional independence within item bundles, and, on the other hand, violations that cannot be attributed to idiosyncratic features of test format and instead suggest departures from unidimensionalty. To this end, two theorems on unidimensional IRT are extended to describe observable item response distributions when there is conditional independencebetween but not necessarilywithin item bundles.The author is grateful to Ivo Molenaar and the referees for many helpful suggestions, and to D. Thayer for assistance with computing.     

A generalized method of image analysis from an intercorrelation matrix which may be singular

Following the works of Guttman (1953) and Kaiser (1976), we show that the image and anti-image covariance matrices can be derived from a singular correlation matrix, by making use of the orthogonal projector and a weaker generalized inverse matrix.     

Maximum likelihood estimation of multivariate polyserial and polychoric correlation coefficients

The method of finding the maximum likelihood estimates of the parameters in a multivariate normal model with some of the component variables observable only in polytomous form is developed. The main stratagem used is a reparameterization which converts the corresponding log likelihood function to an easily handled one. The maximum likelihood estimates are found by a Fletcher-Powell algorithm, and their standard error estimates are obtained from the information matrix. When the dimension of the random vector observable only in polytomous form is large, obtaining the maximum likelihood estimates is computationally rather labor expensive. Therefore, a more efficient method, the partition maximum likelihood method, is proposed. These estimation methods are demonstrated by real and simulated data, and are compared by means of a simulation study.     

The relationship between external variables and common factors

A theorem is presented which gives the range of possible correlations between a common factor and an external variable (i.e., a variable not included in the test battery factor analyzed). Analogous expressions for component (and regression component) theory are also derived. Some situations involving external correlations are then discussed which dramatize the theoretical differences between components and common factors.Support by the National Research Council of Canada (NRC Grant No. A4640) and the University of British Columbia (UBC Humanities and Social Sciences Grant 26-9718) is gratefully acknowledged.This paper is based in part on the author's Ph.D. dissertation. I am particularly grateful to my dissertation advisor, Dr. Peter H. Schönemann. Thanks also to the editor and the anonymous reviewers, who contributed many helpful comments and suggestions.     

高中学生心理应激及其中介变量的研究

学生的心理应激与心理健康问题日益受到人们的关注。本研究对浙江省范围内的４３７名高中学生进行应激源、中介变量和应激反应方面的调查研究,并在此基础上,对高中学生的心理应激过程作了较详细的探讨。研究表明：（１）高中学生的主要应激源是学习压力及与家庭亲友的人际关系问题,（２）对高中学生的应激反应有影响的中介变量主要是社会支持和“问题解决”、“逃避”等应对策略。本研究结论认为,在高中学生的心理卫生工作中要注意减轻他们的学习压力,加强社会支持系统的建立及积极应对方式的教育。