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1.
In a choice situation, it is usually assumed that the agents select the maximal elements. Nevertheless, there are situations in which the number of maximal elements is large, and a selection inside the maximal set is then required. This selection may be done in a random way or, as we propose in this work, by obtaining additional information from the preference relation that may provide a way of discriminating among the maximal elements and selecting the “best” ones.  相似文献   

2.
The authors examined the differences in mean level of cognitive ability and adverse impact that can be expected when selecting employees solely on educational attainment as a proxy for cognitive ability versus selecting employees directly on cognitive ability. Selection using cognitive ability worked as a more efficient cognitive screen. Imposing an educational attainment standard of at least 1 year of college, though, did result in noticeably higher levels of cognitive ability in potential applicant pools than did random selection, meaning that educational attainment does work as a cognitive screen. These results held not only in a nationally representative sample but also within and across 6 different occupational groups. Finally, adverse impact is examined for selection using educational attainment, compared with selection on the basis of cognitive ability.  相似文献   

3.
Content analysis of college students' rationales for selecting employment referents suggests that their choices do not always match with what employers value in reference reports. The concluding section of the article offers suggestions for effective referent selection.  相似文献   

4.
Although top‐down selection is the gold standard for making personnel decisions, several administrative assumptions must be met for it to be effective. We discuss three of these assumptions and test two of them: (1) top applicants will accept an offer, and (2) the time organisations give applicants to consider an offer will not influence the availability of next‐tier applicants. We also examine the effectiveness of top‐down selection by comparing it to an administratively simpler procedure, random selection above a threshold. Using archival admissions data from three university graduate psychology programs, we found that top applicants were less likely to accept an offer; however, waiting time did not influence applicant availability. In comparing the quality of applicants actually selected (with a top‐down procedure) with the quality of applicants selected at random (from above five progressively stringent thresholds), we found that at higher admission thresholds, random selection resulted in better or equal quality applicants as top‐down selection, depending on the criteria. We discuss implications for future research and practice.  相似文献   

5.
In this paper, the extended Rasch model for dichotomously scored items is derived from the general multivariate Bernoulli distribution. The necessary and sufficient conditions for the multivariate Bernoulli distribution to be equal to the extended Rasch model provide a new loglinear representation of the extended Rasch model. Conditions are also given under which the extended Rasch model is equal to the random effects Rasch model, and it is shown under what conditions the extended Rasch model is equal to a random effects Rasch model in which the underlying variable has a normal distribution. In addition, alternative models for the construction of likelihood ratio tests are proposed. One of these alternative models is Haberman's extended interaction model. Furthermore, it is shown how both the SPSS and SAS programs can be used to estimate and test loglinear representations of extended Rasch models.  相似文献   

6.
Hélène Landemore 《Synthese》2013,190(7):1209-1231
This paper argues in favor of the epistemic properties of inclusiveness in the context of democratic deliberative assemblies and derives the implications of this argument in terms of the epistemically superior mode of selection of representatives. The paper makes the general case that, all other things being equal and under some reasonable assumptions, more is smarter. When applied to deliberative assemblies of representatives, where there is an upper limit to the number of people that can be included in the group, the argument translates into a defense of a specific selection mode of participants: random selection.  相似文献   

7.
The most commonly employed item selection rule in a computerized adaptive test (CAT) is that of selecting the item with the maximum Fisher information for the estimated trait level. This means a highly unbalanced distribution of item‐exposure rates, a high overlap rate among examinees and, for item bank management, strong pressure to replace items with a high discrimination parameter in the bank. An alternative for mitigating these problems involves, at the beginning of the test, basing item selection mainly on randomness. As the test progresses, the weight of information in the selection increases. In the present work we study, for two selection rules, the progressive methods ( Revuelta & Ponsoda, 1998 ) and the proportional method ( Segall, 2004a ), different functions that define the weight of the random component according to the position in the test of the item to be administered. The functions were tested in simulated item banks and in an operative bank. We found that both the progressive and the proportional methods tolerate a high weight of the random component with minimal or zero loss of accuracy, while bank security and maintenance are improved.  相似文献   

8.
This study was designed to find the best strategy for selecting the correct multilevel model among several alternatives taking into account variables such as intraclass correlation, number of groups (m), group size (n), or others as parameter values and intercept-slope covariance. First, we examine this question in a simulation study and second, to illustrate the behavior of the criteria and to explore the generalizability of the findings, a previously published educational dataset is analyzed. The results showed that none of the selection criteria behaved correctly under all the conditions or was consistently better than the others. The intraclass correlation somewhat affects the performance of all selection criteria, but the extent of this influence is relatively minor compared to sample size, parameter values, and correlation between random effects. A large number of groups appears more important than a large number of individuals per group in selecting the best model (m  50 and n  20 is suggested). Finally, model selection tools such as Akaike's Information Criterion (AIC) or the conditional AIC are recommend when it is assumed that random effects are correlated, whereas use of the Schwarz's Bayesian Information Criterion or the consistent AIC are advantageous for uncorrelated random effects.  相似文献   

9.
We examined age-related changes of executive functions by means of random noun generation. Consistent with previous observations on random letter generation, older participants produced more prepotent responses than younger ones. In the case of random noun generation, prepotent responses are nouns of the same category as the preceding noun. In contrast to previous observations, older participants exhibited stronger repetition avoidance and a stronger tendency toward local evenness—that is, toward equal frequencies of the alternative responses even in short subsequences. These data suggest that at higher adult age inhibition of prepotent responses is impaired. In addition, strategic attentional processes of response selection are strengthened, in particular the application of a heuristic for randomness. In this sense response selection is more controlled in older than in younger adults.  相似文献   

10.
This pilot study was conducted to determine if clinically-oriented test items are judged to be more offensive than job-related test items. Clinical tests typically ask more personal questions while employment tests usually ask job-relevant questions. A random selection of items from three employment tests was analyzed. Two of the tests evolved from clinical-personality tests, while the third test was designed specifically for employment settings. The results suggest that if companies are interested in using employment tests that are perceived as being job-relevant, inoffensive, and non-invasive, then they should consider selecting tests that include job-relevant items as opposed to tests that are derivatives of clinical assessment instruments.  相似文献   

11.
Choice strategies for selecting among outcomes in multiple-cue probability learning were investigated using a simulated medical diagnosis task. Expected choice probabilities (the proportion of times each outcome was selected given each cue pattern) under alternative choice strategies were constructed from corresponding observed judged probabilities (of each outcome given each cue pattern) and compared with observed choice probabilities. Most of the participants were inferred to have responded by using a deterministic strategy, in which the outcome with the higher judged probability is consistently chosen, rather than a probabilistic strategy, in which an outcome is chosen with a probability equal to its judged probability. Extended practice in the learning environment did not affect choice strategy selection, contrary to reports from previous studies, results of which may instead be attributable to changes with practice in the variability and extremity of the perceived probabilities on which the choices were based.  相似文献   

12.
13.
Application of the concepts of the Neuronal Group Selection Theory (NGST) may shed a new light on motor development. According to NGST, normal motor development is characterized by two phases of variability. Variation is not random, but determined by criteria set by genetic information. Development starts with the phase of primary variability, during which variation in motor behavior is not geared to external conditions. At function-specific ages secondary variability starts, during which motor performance can be adapted to specific situations. In both forms of variability selection on the basis of afferent information plays a significant role. From the NGST point of view, children with pre- or perinatally acquired brain damage suffer from stereotyped motor behavior produced by a limited repertoire of primary (sub)cortical neuronal networks. These children also have problems in selecting the most efficient neuronal activity due to deficits in the processing of sensory information.  相似文献   

14.
It is necessary to recognize the variety of levels at which values and norms may inappropriately affect the equity of the transplantation process, including candidate selection. Using a revised, richer concept of objectivity, adopted from Longino's work in the philosophy of science and empirical studies of candidate selection, this paper examines what sort of objectivity can be obtained in the transplant candidate selection process, and the closely related question of how selection can occur in an equitable manner. This concept of objectivity requires that transformative criticism occur so that (1) the conceptual and normative commitments underlying selection may be articulated and perhaps challenged, and (2) the relationship between those commitments and criteria for candidate selection may be examined and justified, or revised. Through such transformative criticism, a greater degree of objectivity may be attained, which in turn will increase the likelihood of equity.  相似文献   

15.
Abstract

One important concept of experimental design is the random assignment of participants to experimental groups. This randomization process is used to prevent selection bias, as well as to provide a strong basis for a cause-and-effect relationship between the independent variable/s and the dependent variable/s. In small sample sizes, simple randomization may not provide equal groups at baseline for one or more of the variables, and therefore more restricted types of randomization, such as the stratified permuted-block randomization, can be used. A code was written to calculate the probability that simple randomization will not lead to equality between groups at baseline, and then an example of stratified permuted-block randomization was examined. The findings suggest that for certain variables that are commonly measured in experiments in motor learning, there is a relatively high probability that groups will not be equal at baseline after simple randomization. This observation reflects the small sample sizes usually found in the literature on motor learning. However, stratified permuted-block randomization does lead to greater equality among groups. Implications for researchers are discussed, and a flowchart is proposed that will allow researchers to decide whether to use simple or stratified randomization.  相似文献   

16.
When an information processing system is faced with an excess of input information the task of selecting the items which are to get immediate processing is frequently assigned to a human being. A quantitative measure of the extent to which a man avoids random activity during such filtering operations is derived in terms of two parameters (normalized overload and correct proportion of selections) which are determined from experimentally available quantities. This coherence measure may be used for studies of random behavior, comparison of rules for selecting items, and perhaps prediction of human performance at filtering tasks.The author is particularly indebted to Dr. Harold Glaser, of the U. S. Naval Research Laboratory, for many helpful suggestions during the development of this measure.  相似文献   

17.
When the process of publication favors studies with smallp-values, and hence large effect estimates, combined estimates from many studies may be biased. This paper describes a model for estimation of effect size when there is selection based on one-tailedp-values. The model employs the method of maximum likelihood in the context of a mixed (fixed and random) effects general linear model for effect sizes. It offers a test for the presence of publication bias, and corrected estimates of the parameters of the linear model for effect magnitude. The model is illustrated using a well-known data set on the benefits of psychotherapy.Authors' note: The contributions of the authors are considered equal, and the order of authorship was chosen to be reverse-alphabetical.  相似文献   

18.
A working memory selection task combining directed-forgetting and memory-scanning paradigms was used to test the hypothesis that difficulty in selecting target from distractor items in working memory depends on the competition between target and distractor representations, as is commonly assumed in perceptual selection research. Participants memorized two trigrams and were then cued to select one as the new memory set and forget the other. They later saw a test letter and made judgment as to whether the letter was in the selected trigram, i.e., the new memory set. Selection difficulty was examined by manipulating the type of selection cues and the time the cue could be utilized. While re-presenting the targets in the cue display facilitated selection, re-presenting distractors did not impede selection. The results suggest that working memory selection may depend more on the activation from representations of the target than of the distractor.  相似文献   

19.
According to a recent hypothesis, executive functions should be particularly vulnerable to the effects of total sleep deprivation. Random generation is a task that taps executive functions. In three experiments we examined the effects of total sleep deprivation on random generation of keypresses, numbers, and nouns, in particular on the suppression of prepotent responses and the selection of next responses by way of applying a local-representativeness heuristic. With random key-presses suppression of prepotent responses did not suffer from lack of sleep, but it became poorer at a sufficiently high pacing rate. In contrast, suppression of prepotent responses suffered when numbers and nouns were generated. According to these findings different types of random generation tasks involve different types of inhibitory process. With only four response alternatives, but not with larger response sets, application of the local-representativeness heuristic was impaired after a night without sleep. In terms of a simple formal model, serial-order representations of the preceding responses are used in selecting the next response only for the small response set, and not for larger response sets. Thus, serial-order representations are likely to suffer from loss of sleep. These findings strongly suggest that random generation involves multiple processes and that total sleep deprivation does not impair all sorts of executive functions, but only some.  相似文献   

20.
Pillow et al.'s (1991) argument for mediational selection omits discussion of what may be the strategy's greatest advantage, the early identification of risk. The theoretical benefits to prevention of identifying developmental processes are briefly noted here. At the same time, practical limitations of mediational selection are noted, particularly in relation to establishing and interpreting the correlation found between mediational and outcome variables. It is concluded that mediational selection is one, but only one, selection strategy worthy of consideration in prevention research.  相似文献   

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