A model and algorithm for multidimensional scaling with external constraints on the distances

A method for externally constraining certain distances in multidimensional scaling configurations is introduced and illustrated. The approach defines an objective function which is a linear composite of the loss function of the point configurationX relative to the proximity dataP and the loss ofX relative to a pseudo-data matrixR. The matrixR is set up such that the side constraints to be imposed onX's distances are expressed by the relations amongR's numerical elements. One then uses a double-phase procedure with relative penalties on the loss components to generate a constrained solutionX. Various possibilities for constructing actual MDS algorithms are conceivable: the major classes are defined by the specification of metric or nonmetric loss for data and/or constraints, and by the various possibilities for partitioning the matricesP andR. Further generalizations are introduced by substitutingR by a set ofR matrices,R _i ,i=1, ...r, which opens the way for formulating overlapping constraints as, e.g., in patterns that are both row- and column-conditional at the same time.     

Interim Managers: Distinguishing Personality Characteristics of Managers on Short-term Contracts

The use of interim managers by companies is increasing, and reasons for this trend are discussed. A study is reported in which the normative personality make-up of a group of interim managers is compared with that of a general sample of UK managers. Ninety-four interim managers completed the revised PA Preference Inventory (PAPI-N) and the results are compared with those from a general UK managerial sample. Statistically significant differences are reported for 12 out of 20 scales, with nine of the effect sizes ≥ 0.5. Results are also compared with a priori job expert predictions. Of nine predictions that interim managers would differ from the general management norm, seven are consistent with the statistical findings. Practical and methodological implications of the findings, and their relation to the ‘Big Five’, are discussed, together with broader implications for the study of workers in new and emerging forms of employment. The findings are also interpreted in the particular context of interim management roles.     

Book Reviews

Books reviewed: Robert Shaw Trust in the Balance; Building Successful Organizations on Results, Integrity and Concern Louis H. Janda Psychological Testing: Theory and Applications David Ulrich, Michael R. Losey and Geraldine Lake, (eds) Tomorrow's HR Management: 48 Thought Leaders Call For Change     

Book Reviews

John Arnold, Cary Cooper and Ivan T. Robinson, Work Psychology Jan Te Nijenhuis, Comparability of Test Scores for Immigrants and Majority Group Members in the Netherlands David A. Nadler with Mark B. Nadler, Champions of Change: How CEO’s and their Companies are Mastering the Skills of Radical Change     

Duty to Re-Contact: A Study of Families at Risk for Fragile X

DNA testing for Fragile X syndrome is now routinely available through a large number of diagnostic laboratories. We have surveyed individuals from British Columbia Fragile X families identified prior to the availability of DNA testing for FMR1 to determine if they are subsequently receiving information about DNA testing. Of the 78 individuals first seen before the cloning of the FMR1 gene, 39 (50%) had not been seen in the clinic to discuss DNA testing. We initiated a contact program with these 39 patients to determine their interest in DNA testing. Contact was made with 28 individuals, 20 of whom stated interest in testing either for themselves or for a relative. Patient opinions about DNA testing were assessed through questionnaires. In those individuals who stated an interest in DNA testing, the most common reason for wishing testing was to provide information to children or grandchildren. The most common disadvantages of testing indicated by this group were that they had finished their families and that they felt the test would not have a direct impact. The most common reasons individuals were not interested in DNA testing were that there were no family members appropriate to test and that the respondent had completed his or her family. DNA testing has been performed for 13 of the 28 (46%) contacted individuals and/or at least one relative. In view of the high level of interest for testing in families who had not been seen since the cloning of the FMR1 gene, we feel that FMR1 screening programs should include actively contacting previously seen individuals.     

Getting real in analysis

The author uses a detailed clinical example to illustrate how reality testing can create rather than foreclose opportunities for analytic investigation. He proposes that authentic analysis of transference within the treatment relationship requires close and explicit attention to be paid to considerations of reality, but in a way that does not require the patient to defer to the analyst's view. The author reconsiders certain conceptions of a special psychoanalytic reality, of regression in clinical analysis, and of the nature of free association, suggesting that they tend to discourage the realism necessary to effective psychoanalytic work. In this context, he underlines the importance of ongoing reference to therapeutic outcome as an aspect of reality, and reflects upon the impact of the reality of the analytic treatment setting and the question of termination.     

Loglinear multidimensional IRT models for polytomously scored items

A loglinear IRT model is proposed that relates polytomously scored item responses to a multidimensional latent space. The analyst may specify a response function for each response, indicating which latent abilities are necessary to arrive at that response. Each item may have a different number of response categories, so that free response items are more easily analyzed. Conditional maximum likelihood estimates are derived and the models may be tested generally or against alternative loglinear IRT models.Hank Kelderman is currently affiliated with Vrije Universiteit, Amsterdam.We thank Linda Vodegel-Matzen of the Division of Developmental Psychology of the University of Amsterdam for making available the data used in the example in this article.     

Constructing measures with maximum reliability

The scoring of response vectors to give maximum test-retest correlation is investigated. Simple sufficiency arguments show that the form of the best scores is very restricted. A general method is given for finding the best scores, deriving the best scores for the normal factor model, and showing by calculation of several particular cases that for a standard model for binary response it is easy to approximate the best scores.     

Toddlers’ social evaluations of agents who act on false beliefs

Mature social evaluations privilege agents’ intentions over the outcomes of their actions, but young children often privilege outcomes over intentions in verbal tasks probing their social evaluations. In three experiments (N = 118), we probed the development of intention-based social evaluation and mental state reasoning using nonverbal methods with 15-month-old toddlers. Toddlers viewed scenarios depicting a protagonist who sought to obtain one of two toys, each inside a different box, as two other agents observed. Then, the boxes’ contents were switched in the absence of the protagonist and either in the presence or the absence of the other agents. When the protagonist returned, one agent opened the box containing the protagonist's desired toy (a positive outcome), and the other opened the other box (a neutral outcome). When both agents had observed the toys move to their current locations, the toddlers preferred the agent who opened the box containing the desired toy. In contrast, when the agents had not seen the toys move and therefore should have expected the desired toy's location to be unchanged, the toddlers preferred the agent who opened the box that no longer contained the desired toy. Thus, the toddlers preferred the agent who intended to make the protagonist's desired toy accessible, even when its action, guided by a false belief concerning that toy's location, did not produce a positive outcome. Well before children connect beliefs to social behavior in verbal tasks, toddlers engage in intention-based evaluations of social agents with false beliefs.     

可修改答案的计算机化自适应测验的方法

与传统的纸笔测验(Paper And Pencil Based Test, P&P)相比计算机化自适应测验(Computerized Adaptive Testing, CAT)根据被试的作答反应自适应地选择题目, 它不仅缩短了测验长度, 还极大地提高了测验的准确性。然而, 目前绝大多数CAT不允许被试修改答案, 研究者主要担心修改答案会降低CAT的有效性。允许修改答案符合被试一贯的测验习惯, 修改之后的分数更能反映被试真实的水平, 从而能够进一步促进CAT在实际中的应用。现有的研究主要从三个方面提出了可修改答案CAT的控制方法：一是测验设计; 二是改进选题策略; 三是建构模型。未来的研究应进一步探讨这些方法之间的比较与结合, 以及对可修改答案认知诊断CAT (Cognitive Diagnostic CAT, CD-CAT)的研究。