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951.
When there are order constraints among the parameters of a binary, multinomial processing tree (MPT) model, methods have been developed for reparameterizing the constrained MPT into an equivalent unconstrained MPT. This note provides a theorem that is useful in computing bounds on the estimator variances for the parameters of the constrained model in terms of estimator variances of the parameters of the unconstrained model. In particular, we show that if X and Y are random variables taking values in [0,1], then Var[XY]?2(Var[X]+Var[Y]).  相似文献   
952.
We enrich intuitionistic logic with a lax modal operator and define a corresponding intensional enrichment of Kripke models M = (W, , V) by a function T giving an effort measure T(w, u) {} for each -related pair (w, u). We show that embodies the abstraction involved in passing from true up to bounded effort to true outright. We then introduce a refined notion of intensional validity M |= p : and present a corresponding intensional calculus iLC-h which gives a natural extension by lax modality of the well-known G: odel/Dummett logic LC of (finite) linear Kripke models. Our main results are that for finite linear intensional models L the intensional theory iTh(L) = {p : | L |= p : } characterises L and that iLC-h generates complete information about iTh(L).Our paper thus shows that the quantitative intensional information contained in the effort measure T can be abstracted away by the use of and completely recovered by a suitable semantic interpretation of proofs.  相似文献   
953.
Three experiments assessed the contributions of age-of-acquisition (AoA) and frequency to visual word recognition. Three databases were created from electronic journals in chemistry, psychology and geology in order to identify technical words that are extremely frequent in each discipline but acquired late in life. In Experiment 1, psychologists and chemists showed an advantage in lexical decision for late-acquired/high-frequency words (e.g. a psychologist responding to cognition) over late-acquired/low-frequency words (e.g. a chemist responding to cognition), revealing a frequency effect when words are perfectly matched. However, contrary to theories that exclude AoA as a factor, performance was similar for the late-acquired/high-frequency and early-acquired/low-frequency words (e.g. dragon) even though their cumulative frequencies differed by more than an order of magnitude. This last finding was replicated with geologists using geology words matched with early-acquired words in terms of concreteness (Experiment 2). Most interestingly, Experiment 3 yielded the same pattern of results in naming while controlling for imageability, a finding that is particularly problematic for parallel distributed processing models of reading.  相似文献   
954.
A multivariate reduced-rank growth curve model is proposed that extends the univariate reducedrank growth curve model to the multivariate case, in which several response variables are measured over multiple time points. The proposed model allows us to investigate the relationships among a number of response variables in a more parsimonious way than the traditional growth curve model. In addition, the method is more flexible than the traditional growth curve model. For example, response variables do not have to be measured at the same time points, nor the same number of time points. It is also possible to apply various kinds of basis function matrices with different ranks across response variables. It is not necessary to specify an entire set of basis functions in advance. Examples are given for illustration.The work reported in this paper was supported by Grant A6394 from the Natural Sciences and Engineering Research Council of Canada to the second author. We thank Jennifer Stephan for her helpful comments on an earlier version of this paper. We also thank Patrick Curran and Terry Duncan for kindly letting us use the NLSY and substance use data, respectively. The substance use data were provided by Grant DA09548 from the National Institute on Drug Abuse.  相似文献   
955.
956.
Wendy M. Yen 《Psychometrika》1985,50(4):399-410
When the three-parameter logistic model is applied to tests covering a broad range of difficulty, there frequently is an increase in mean item discrimination and a decrease in variance of item difficulties and traits as the tests become more difficult. To examine the hypothesis that this unexpected scale shrinkage effect occurs because the items increase in complexity as they increase in difficulty, an approximate relationship is derived between the unidimensional model used in data analysis and a multidimensional model hypothesized to be generating the item responses. Scale shrinkage is successfully predicted for several sets of simulated data.The author is grateful to Robert Mislevy for kindly providing a copy of his computer program, RESOLVE.  相似文献   
957.
    
《创造性行为杂志》2017,51(4):293-296
This paper presents a framework for conceptualizing work on creativity in terms of 7 C's. These are: Creators, Creating, Collaborations, Contexts, Creations, Consumption, and Curricula. The content of these thema are described and situated with respect to previous proposals.  相似文献   
958.
    
《创造性行为杂志》2017,51(4):345-347
The Journal of Creative Behavior 's remarkable half‐century is a good occasion for reflecting on the role of a scholarly field's institutions in fostering creative work. In creativity studies, some of our institutions are flourishing, particularly our many excellent peer‐reviewed journals. But we face some institutional challenges that will require some creative solutions from creativity researchers. This article considers three challenges: (a) how to train and place the next generation of scholars when so few creativity researchers work at doctoral‐level graduate programs; (b) how to tighten the field's social network by bringing together people from different subfields and career stages in face‐to‐face gatherings; and (c) how to identify and develop the leadership needed to manage our scholarly organizations.  相似文献   
959.
    
This paper introduces the relational triangulation framework as a functional contextual expansion of the established Relational Frame Theory (Hayes, Barnes‐Holmes, & Roche, 2001) account of perspective‐taking. Initial support for the new framework is provided through data collected with a novel relational triangulation perspective‐taking protocol configured in the present study to show contextual influence over deriving true belief in others following the direct training of a “seeing leads to knowing” repertoire (Leslie & Frith, 1988). Eight verbally competent adults were directly trained to make operant discriminations on a first set of target stimuli (i.e., the identities of three distinct figurines) and then directly trained to make contextually controlled deictic pointing responses to a second set of target stimuli (i.e., to the relative location of a target beacon according to the signaled spatial perspective of the self vs. two others). The test for derivation was whether the stimuli that had directly acquired contextual control over deictic perspective‐taking during training would spontaneously exert contextual control over figurine discrimination relative to the spatial perspective of the two others. That is, passing the test for derivation required participants to infer that the others would “report what they were seeing” the same way that the self would if the self were in their position, suggesting coordination of the self and others. Seven of the eight participants exhibited the intended derivation of the others' “true beliefs,” confirming successful relational triangulation perspective‐taking protocol configuration for this purpose.  相似文献   
960.
    
Researchers often build regression models to relate a response to a set of predictor variables. In some cases, there are predictors that apply to some participants, or to some measurement occasions, but not others. For example, a romantic partner's substance use may be a key predictor of one's own substance use. However, not all participants have a partner, and in a longitudinal study, participants may have a partner during only some occasions. This could be viewed as missing data, but of a very distinctive type: the values are not just unknown but also undefined. In this paper, we present a simple method to accommodate this situation, along with a motivating example, the algebraic justification, a simulation study, and examples on how to carry out the technique.  相似文献   
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