An approximation for the bias function of the maximum likelihood estimate of a latent variable for the general case where the item responses are discrete

Lord developed an approximation for the bias function for the maximum likelihood estimate in the context of the three-parameter logistic model. Using Taylor's expansion of the likelihood equation, he obtained an equation that includes the conditional expectation, given true ability, of the discrepancy between the maximum likelihood estimate and true ability. All terms of orders higher thann ^?1 are ignored wheren indicates the number of items. Lord assumed that all item and individual parameters are bounded, all item parameters are known or well-estimated, and the number of items is reasonably large. In the present paper, an approximation for the bias function of the maximum likelihood estimate of the latent trait, or ability, will be developed using the same assumptions for the more general case where item responses are discrete. This will include the dichotomous response level, for which the three-parameter logistic model has been discussed, the graded response level and the nominal response level. Some observations will be made for both dichotomous and graded response levels.     

Logistic positive exponent family of models: Virtue of asymmetric item characteristic curves

The paper addresses and discusses whether the tradition of accepting point-symmetric item characteristic curves is justified by uncovering the inconsistent relationship between the difficulties of items and the order of maximum likelihood estimates of ability. This inconsistency is intrinsic in models that provide point-symmetric item characteristic curves, and in this paper focus is put on the normal ogive model for observation. It is also questioned if in the logistic model the sufficient statistic has forfeited the rationale that is appropriate to the psychological reality. It is observed that the logistic model can be interpreted as the case in which the inconsistency in ordering the maximum likelihood estimates is degenerated.The paper proposes a family of models, called the logistic positive exponent family, which provides asymmetric item chacteristic curves. A model in this family has a consistent principle in ordering the maximum likelihood estimates of ability. The family is divided into two subsets each of which has its own principle, and includes the logistic model as a transition from one principle to the other. Rationale and some illustrative examples are given.     

Novel odors evoke risk assessment and suppress appetitive behaviors in mice

The effects of four novel odors on risk assessment by mice (i. e., flat back approach, stretched attention, immobility) and the suppression of appetitive behaviors were examined in two experiments. When novel odors were presented in a straight runway, subjects spent significantly less time in the odor compartment, relative to controls, when it contained sheep wool, chocolate, or citronella (but not cat fur) odors. Risk assessment behaviors occurred at similar levels among all groups and appetitive behaviors were not suppressed by the novel odors. When odorants were scattered over one half of the subjects' home cage floor in Experiment 2, all novel odors increased the duration of at least on e risk assessment measure and/or suppressed appetitive behaviors (i. e., eating, grooming, rearing). The results clearly reveal that a reasonably wide range of novel odors evoke at least some level of risk assessment which presumably reflects increased fearfulness. The odors of sheep wool and cat fur induced a wider range of such responses than did chocolate or cinnamon suggesting that mammalian odors may be particularly effective stimuli. If so, however, it is clear that predator odors are not uniquely effective in this regard. Experiment 1 also underscores the importance of the testing environment in assessing the behavioral effects of novel odors in mice. © 1993 Wiley-Liss, Inc.     

先秦服饰色彩与现代服装设计

民族风格的服装一直是现代服装设计主要潮流,中华民族有着悠久的服饰文化历史,一些民族的元素或多或少地也出现一些现代设计中,但总的来说,不是很系统。服装设计的继承不能只停留在形制的模仿上,而是要从文化的层面上融会传统服饰的精髓,用神似的手法进行设计。本文分析了中华服饰的色彩文化的形成和色彩文化的哲学基础。从先民对色彩的认识、色彩的运用和染色技术等方面论证,显示了中华民族优秀的服饰文明,同时也给我们在现代服装设计中色彩的运用提供了很好的启示。     

Examining the Association Between Racial Identity Attitudes and Coping With Racism-Related Stress

The authors examined the association between racial identity attitudes and coping with racism-related stress among Asian, Black, and Latinx college students (N = 195). Results of the canonical correlation analysis indicated that higher scores on a combination of all racial identity attitudes were significantly associated with greater active coping for Black and Latinx students. Among Asian students, the authors found that higher scores on conformity, dissonance, and immersion-emersion racial identity attitudes were significantly associated with greater avoidant coping. Los autores examinaron la asociación entre las actitudes de identidad racial y el afrontamiento del estrés relacionado con el racismo en estudiantes universitarios asiáticos, negros y latinxs (N = 195). Los resultados del análisis de correlación canónica indicaron que unos valores más altos en la combinación de todas las actitudes de identidad racial estaban asociados significativamente a un mayor afrontamiento activo en estudiantes negros y latinxs. En estudiantes asiático-americanos, los autores hallaron que unos valores más altos en las actitudes de identidad racial de conformidad, disonancia e inmersión/emersión estaban asociados significativamente a un mayor afrontamiento evasivo.     

A hierarchical latent response model for inferences about examinee engagement in terms of guessing and item-level non-response

In low-stakes assessments, test performance has few or no consequences for examinees themselves, so that examinees may not be fully engaged when answering the items. Instead of engaging in solution behaviour, disengaged examinees might randomly guess or generate no response at all. When ignored, examinee disengagement poses a severe threat to the validity of results obtained from low-stakes assessments. Statistical modelling approaches in educational measurement have been proposed that account for non-response or for guessing, but do not consider both types of disengaged behaviour simultaneously. We bring together research on modelling examinee engagement and research on missing values and present a hierarchical latent response model for identifying and modelling the processes associated with examinee disengagement jointly with the processes associated with engaged responses. To that end, we employ a mixture model that identifies disengagement at the item-by-examinee level by assuming different data-generating processes underlying item responses and omissions, respectively, as well as response times associated with engaged and disengaged behaviour. By modelling examinee engagement with a latent response framework, the model allows assessing how examinee engagement relates to ability and speed as well as to identify items that are likely to evoke disengaged test-taking behaviour. An illustration of the model by means of an application to real data is presented.     

Conscious perception of flickering stimuli in binocular rivalry and continuous flash suppression is not affected by tACS-induced SSR modulation

The content of conscious perception is known to correlate with steady-state responses (SSRs), yet their causal relationship remains unclear. Can we manipulate conscious perception by directly interfering with SSRs through transcranial alternating current stimulation (tACS)? Here, we directly addressed this question in three experiments involving binocular rivalry and continuous flash suppression (CFS). Specifically, while participants (N = 24) viewed either binocular rivalry or tried to detect stimuli masked by CFS, we applied sham or real tACS across parieto-occipital cortex at either the same or a different frequency and phase as an SSR eliciting flicker stimulus. We found that tACS did not differentially affect conscious perception in the forms of predominance, CFS detection accuracy, reaction time, or metacognitive sensitivity, confirmed by Bayesian statistics. We conclude that tACS application at frequencies of stimulus-induced SSRs does not have perceptual effects and that SSRs may be epiphenomenal to conscious perception.     

Effects of suppression and acceptance on emotional responses of individuals with anxiety and mood disorders

The present investigation compared the subjective and physiological effects of emotional suppression and acceptance in a sample of individuals with anxiety and mood disorders. Sixty participants diagnosed with anxiety and mood disorders were randomly assigned to one of two groups. One group listened to a rationale for suppressing emotions, and the other group listened to a rationale for accepting emotions. Participants then watched an emotion-provoking film and applied the instructions. Subjective distress, heart rate, skin conductance level, and respiratory sinus arrhythmia were measured before, during, and after the film. Although both groups reported similar levels of subjective distress during the film, the acceptance group displayed less negative affect during the post-film recovery period. Furthermore, the suppression group showed increased heart rate and the acceptance group decreased heart rate in response to the film. There were no differences between the two groups in skin conductance or respiratory sinus arrhythmia. These findings are discussed in the context of the existing body of research on emotion regulation and current treatment approaches for anxiety and mood disorders.     

Navigating Social Class Roles in Community Research

This paper describes the first author's attempt to collect data in a homeless shelter without attending to her role in the social class hierarchy of the organization. The author's egalitarian approach towards the homeless clients, and her lack of involvement in "staff-only" activities, transgress the social class norms within the organizational structure. While the author is successful in gaining the trust of the homeless clients, her approach alienates shelter staff, especially those in the higher echelons of the social hierarchy. The concepts of classism, world views, and Social Identity Theory, are utilized to discuss the dilemma faced by researchers who want to challenge, or work outside, a setting's status quo.     

Dimensionality of psychosocial responses to marital disruption

The purpose of the study was to assess whether psychosocial responses to marital disruption were best arranged along one single dimension ranging from maximum positive to maximum negative responses, or whether positive and negative responses constituted two separate and distinct dimensions. Participants were 658 recently divorced individuals. A confirmatory factor analysis revealed that a two-factor model provided a better fit to the data than a one-factor model. Moreover, a number of external variables differentiated between positive and negative responses, indicating that such responses reflect two separate domains. Thus, the findings support the notion that psychosocial responses after marital disruption comprise a bidimensional rather than a unidimensional pattern. The findings are discussed within the general framework of positive-negative asymmetry and the idea that positive and negative evaluations belong to different psychological system.