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131.
Fitting and testing carroll's weighted unfolding model for preferences   总被引:1,自引:0,他引:1  
A quadratic programming algorithm is presented for fitting Carroll's weighted unfolding model for preferences to known multidimensional scale values. The algorithm can be applied directly to pairwise preferences; it permits nonnegativity constraints on subject weights; and it provides a means of testing various preference model hypotheses. While basically metric, it can be combined with Kruskal's monotone regression to fit ordinal data. Monte Carlo results show that (a) adequacy of true preference recovery depends on the number of data points and the amount of error, and (b) the proportion of data variance accounted for by the model sometimes only approximately reflects true recovery.This study is based on a doctoral dissertation submitted to the University of Illinois at Urbana-Champaign. The author wishes to thank the members of his dissertation committee—Lawrence E. Jones, Chairman, Charles Lewis, Stephen Golding, Ledyard Tucker, and Nancy Wiggins—for their helpful comments.  相似文献   
132.
Taking Catholic sexual ethics and liberal feminist ethics as points of departure, this essay argues that both frameworks are ill‐prepared to deal with the moral problems raised by sex trafficking: while Catholic sexual ethics is grounded in a normative understanding of sexuality, liberal feminist ethics argues for women's sexual autonomy, resting upon freedom of action and consent. From a perspective that attends both to the phenomenological interpretation of embodied selves and the Kantian normative interpretation of dignity, it becomes possible to critique both the Catholic and the liberal feminist frameworks of ethics. I argue that Catholic sexual ethics requires a reconceptualization as social ethics in order to meet the challenges of our present time, but that the shift is possible without giving up the moral imperatives of both Catholic and feminist ethics to protect human dignity and women's rights.  相似文献   
133.
In the research area of multiple criteria decision making, very few publications exist that explicitly design the simulation of a decision maker (DM) in an interactive approach. For this reason, we outline some methods widely used in the literature to identify common assumptions of simulating the DM's responses and the required input preference information. Our paper aims at covering the identified gap by introducing experimental concepts. Such concepts are used for theoretical analyses of a combined search‐and‐decision‐making procedure. Simulating the DM is a fruitful idea because the algorithm can be tested without integrating a human decision maker. Finally, we conduct experiments based on the proposed settings for a multiobjective inventory routing problem, which is a relevant and challenging logistic problem. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
134.
Using Louis’ formula, it is possible to obtain the observed information matrix and the corresponding large-sample standard error estimates after the expectation–maximization (EM) algorithm has converged. However, Louis’ formula is commonly de-emphasized due to its relatively complex integration representation, particularly when studying latent variable models. This paper provides a holistic overview that demonstrates how Louis’ formula can be applied efficiently to item response theory (IRT) models and other popular latent variable models, such as cognitive diagnostic models (CDMs). After presenting the algebraic components required for Louis’ formula, two real data analyses, with accompanying numerical illustrations, are presented. Next, a Monte Carlo simulation is presented to compare the computational efficiency of Louis’ formula with previously existing methods. Results from these presentations suggest that Louis’ formula should be adopted as a standard method when computing the observed information matrix for IRT models and CDMs fitted with the EM algorithm due to its computational efficiency and flexibility.  相似文献   
135.
Many studies indicate that increasing self-awareness leads to individuals reflecting on their values and ideals (Silvia & Duval, 2001). This self-reflection appears to increase prosocial behaviour (Berkowitz, 1987). However, previously studies typically manipulated self-awareness in situations in which the individual may have felt pressure from the researcher to help. Thus, experimenter pressure to behave prosocially confounds the self-awareness explanation provided in past research. We used a novel experimental paradigm to manipulate self-awareness and remove the researcher's presence to decrease the likelihood that the participant would conform to experimenter demand. Participants were 36 college students (Mage = 19.52; 25 women). The results indicated a strong probability that the experimental condition participants were more prosocial than control condition participants. These findings provide additional support for the hypothesis that self-reflection increases prosocial behaviour, even without experimenter demands. These findings and the importance of studying objective self-awareness in light of the coronavirus are discussed.  相似文献   
136.
PurposeThe purpose of this study was to examine dysfluency characteristics of individuals with Parkinson Disease (PD) relative to linguistic features of grammatical class and position within word. Few studies have reported dysfluency characteristics of PD relative to these characteristics. Those that do report on these characteristics include one case study and a study of six individuals with PD. No previous research is known to have examined dysfluency related to grammatical class and position within words for a large sample of individuals with PD.MethodDysfluencies from 32 individuals with PD were analyzed according to position within a word and grammatical class.ResultsParticipants produced significantly more dysfluencies in the initial position of words compared to medial or final positions, and a significantly higher percent dysfluency for content words versus function words.ConclusionEffects of linguistic features of grammatical class and position within a word on dysfluencies are present within a population with PD and are similar to the linguistic features associated with developmental stuttering. Clinical implications of the effect of linguistic features on speech dysfluencies in PD are discussed.  相似文献   
137.
In analyzing responses and response times to personality questionnaire items, models have been proposed which include the so-called “inverted-U effect.” These models predict that response times to personality test items decrease as the latent trait value of a given person gets closer to the attractiveness of an item. Initial studies into these models have focused on dichotomous personality items, and more recently, models for Likert-type scale items have been proposed. In all these models, it is assumed that the inverted-U effect is symmetrical around 0, while, as will be explained in this article, there are substantive and statistical reasons to study this assumption. Therefore, in this article, a general inverted-U model is proposed which accommodates two sources of asymmetry between the response times and the attractiveness of the items. The viability of this model is demonstrated in a simulation study, and the model is applied to the responses and response times of the Temperament and Character Inventory–Revised, covering a broad range of personality dimensions.  相似文献   
138.
Politicians are influential both in directing policies about refugees and in framing public discourse about them. However, unlike other host country residents, politicians' attitudes towards refugees and integration are remarkably understudied. We therefore examine similarities and differences between politicians' attitudes towards refugee integration and those held by citizens. Based on the stereotype content model, we expect that political ideology informs stereotypes about refugees, which subsequently shape attitudes towards refugee integration. Based on the Contact Hypothesis, we further argue that personal contact with refugees reduces negative stereotypes about them—in particular for those endorsing a right-wing ideology. We draw on data collected via two surveys with 905 politicians and 8013 citizens in the Netherlands to show that (1) unlike those with a left-wing orientation, residents (i.e., both politicians and citizens) with a right-wing orientation hold more negative stereotypes about refugees, which in turn relate to more negative attitudes towards refugee integration; (2) personal contact with refugees is associated with less negative stereotypes among residents; and (3) politicians, compared to citizens, report less negative stereotypes and more positive attitudes towards refugee integration. The practical implication of fostering residents' contact with refugees as well as the implications for future research are discussed.  相似文献   
139.
140.
Previous research on support for gender quotas focuses on attitudes toward gender equality and government intervention as explanations. We argue the role of attitudes toward women in understanding support for policies aiming to increase the presence of women in politics is ambivalent—both hostile and benevolent forms of sexism contribute in understanding support, albeit in different ways. Using original data from a survey conducted on a probability-based sample of Australian respondents, our findings demonstrate that hostile sexists are more likely to oppose increasing of women's presence in politics through the adoption of gender quotas. Benevolent sexists, on the other hand, are more likely to support these policies than respondents exhibiting low levels of benevolent sexism. We argue this is because benevolent sexism holds that women are pure and need protection; they do not have what it takes to succeed in politics without the assistance of quotas. Finally, we show that while women are more likely to support quotas, ambivalent sexism has the same relationship with support among both women and men. These findings suggest that aggregate levels of public support for gender quotas do not necessarily represent greater acceptance of gender equality generally.  相似文献   
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