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1.
2.
Erling B. Andersen 《Psychometrika》1973,38(1):123-140
The Rasch model is an item analysis model with logistic item characteristic curves of equal slope,i.e. with constant item discriminating powers. The proposed goodness of fit test is based on a comparison between difficulties
estimated from different scoregroups and over-all estimates.
Based on the within scoregroup estimates and the over-all estimates of item difficulties a conditional likelihood ratio is
formed. It is shown that—2 times the logarithm of this ratio isx
2-distributed when the Rasch model is true.
The power of the proposed goodness of fit test is discussed for alternative models with logistic item characteristic curves,
but unequal discriminating items from a scholastic aptitude test. 相似文献
3.
André Beauducel 《Psychometrika》2007,72(3):437-441
It was investigated whether commonly used factor score estimates lead to the same reproduced covariance matrix of observed variables. This was achieved by means of Schönemann and Steiger’s (1976) regression component analysis, since it is possible to compute the reproduced covariance matrices of the regression components corresponding to different factor score estimates. It was shown that Thurstone’s, Ledermann’s, Bartlett’s, Anderson-Rubin’s, McDonald’s, Krijnen, Wansbeek, and Ten Berge’s, as well as Takeuchi, Yanai, and Mukherjee’s score estimates reproduce the same covariance matrix. In contrast, Harman’s ideal variables score estimates lead to a different reproduced covariance matrix. 相似文献
4.
Jennifer Lackey 《Synthese》2007,158(3):345-361
A view of knowledge—what I call the Deserving Credit View of Knowledge(DCVK)—found in much of the recent epistemological literature, particularly among so-called virtue epistemologists, centres
around the thesis that knowledge is something for which a subject deserves credit. Indeed, this is said to be the central difference between those true beliefs that qualify as knowledge and those that are true merely by luck—the former, unlike the latter,
are achievements of the subject and are thereby creditable to her. Moreover, it is often further noted that deserving credit
is what explains the additional value that knowledge has over merely lucky true belief. In this paper, I argue that the general conception of knowledge found in
the DCVK is fundamentally incorrect. In particular, I show that deserving credit cannot be what distinguishes knowledge from
merely lucky true belief since knowledge is not something for which a subject always deserves credit. 相似文献
5.
Regression among factor scores 总被引:1,自引:0,他引:1
Structural equation models with latent variables are sometimes estimated using an intuitive three-step approach, here denoted
factor score regression. Consider a structural equation model composed of an explanatory latent variable and a response latent
variable related by a structural parameter of scientific interest. In this simple example estimation of the structural parameter
proceeds as follows: First, common factor models areseparately estimated for each latent variable. Second, factor scores areseparately assigned to each latent variable, based on the estimates. Third, ordinary linear regression analysis is performed among the
factor scores producing an estimate for the structural parameter. We investigate the asymptotic and finite sample performance
of different factor score regression methods for structural equation models with latent variables. It is demonstrated that
the conventional approach to factor score regression performs very badly. Revised factor score regression, using Regression
factor scores for the explanatory latent variables and Bartlett scores for the response latent variables, produces consistent
estimators for all parameters. 相似文献
6.
Two current methods of deriving common-factor scores from tests are briefly examined and rejected. One of these estimates a score from a multiple-regression equation with as many terms as there are tests in the battery. The other limits the equation to a few tests heavily saturated with the desired factor, with or without tests used to suppress the undesired factors. In the proposed methods, the single best test for each common factor is the starting point. Such a test ordinarily has a very few undesired factors to be suppressed, frequently only one. The suppression test should be univocal, or nearly so. Fortunately, there are relatively univocal tests for factors that commonly require suppression. Equations are offered by which the desired-factor test and a single suppression test can be weighted in order to achieve one or more objectives. Among the objectives are (1) maximizing the desired factor variance, (2) minimizing the undesired factor variance, (3) a compromise, in which the undesired variance is materially reduced without loss in desired variance, and (4) a change to any selected ratio of desired to undesired variance. A more generalized solution is also suggested. The methods can be extended in part to the suppression of more than one factor. Equations are derived for the suppression of two factors. 相似文献
7.
John M. Ferron Bethany A. Bell Melinda R. Hess Gianna Rendina-Gobioff Susan T. Hibbard 《Behavior research methods》2009,41(2):372-384
Multiple-baseline studies are prevalent in behavioral research, but questions remain about how to best analyze the resulting
data. Monte Carlo methods were used to examine the utility of multilevel models for multiplebaseline data under conditions
that varied in the number of participants, number of repeated observations per participant, variance in baseline levels, variance
in treatment effects, and amount of autocorrelation in the Level 1 errors. Interval estimates of the average treatment effect
were examined for two specifications of the Level 1 error structure (σ2
I and first-order autoregressive) and for five different methods of estimating the degrees of freedom (containment, residual,
between—within, Satterthwaite, and Kenward—Roger). When the Satterthwaite or Kenward—Roger method was used and an autoregressive
Level 1 error structure was specified, the interval estimates of the average treatment effect were relatively accurate. Conversely,
the interval estimates of the treatment effect variance were inaccurate, and the corresponding point estimates were biased. 相似文献
8.
A general one-way analysis of variance components with unequal replication numbers is used to provide unbiased estimates of
the true and error score variance of classical test theory. The inadequacy of the ANOVA theory is noted and the foundations
for a Bayesian approach are detailed. The choice of prior distribution is discussed and a justification for the Tiao-Tan prior
is found in the particular context of the “n-split” technique. The posterior distributions of reliability, error score variance, observed score variance and true score
variance are presented with some extensions of the original work of Tiao and Tan. Special attention is given to simple approximations
that are available in important cases and also to the problems that arise when the ANOVA estimate of true score variance is
negative. Bayesian methods derived by Box and Tiao and by Lindley are studied numerically in relation to the problem of estimating
true score. Each is found to be useful and the advantages and disadvantages of each are discussed and related to the classical
test-theoretic methods. Finally, some general relationships between Bayesian inference and classical test theory are discussed.
Supported in part by the National Institute of Child Health and Human Development under Research Grant 1 PO1 HDO1762. Reproduction,
translation, use or disposal by or for the United States Government is permitted. 相似文献
9.
Sehee Hong 《Behavior research methods》1999,31(4):727-730
Most simulation studies in factor analysis follow a process of constructing population correlation matrices from the common-factor model and generating sample correlation matrices from the population matrices. In the common-factor model, the population correlation matrix is perfectly fit by the model’s containing common and unique factors. However, since no mathematical model accounts exactly for the real-world phenomena that it is intended to represent, the Tucker-Koopman-Linn model (1969) is more realistic for generating correlation matrices than the conventional common-factor model because the former incorporates model error. In this paper, a procedure for generating population and sample correlation matrices with model error by combining the Tucker-Koopman-Linn model and Wijsman’s algorithm (1959) is presented. The SAS/ IML program for generating correlation matrices is described, and an example is also provided. 相似文献
10.
Ledyard R Tucker 《Psychometrika》1971,36(4):427-436
Considerations of factor score estimates have concentrated on internal characteristics. This report considers external characteristics of four methods for determining factor score estimates; that is, relations of these estimates to measures on attributes not entered into the factor analysis. These external characteristics are important for many uses of factor score estimates. Findings are that different ones of the methods are appropriate for different uses.Supported in part by the Personnel and Training Branch of the Office of Naval Research under contract number 00014-67-A-0305-0003. 相似文献
11.
In the tripartite model of working memory (WM) it is postulated that a unique part system—the visuo-spatial sketchpad (VSSP)—processes
non-verbal content. Due to behavioral and neurophysiological findings, the VSSP was later subdivided into visual object and
visual spatial processing, the former representing objects’ appearance and the latter spatial information. This distinction
is well supported. However, a challenge to this model is the question how spatial information from non-visual sensory modalities,
for example the auditory one, is processed. Only a few studies so far have directly compared visual and auditory spatial WM.
They suggest that the distinction of two processing domains—one for object and one for spatial information—also holds true
for auditory WM, but that only a part of the processes is modality specific. We propose that processing in the object domain
(the item’s appearance) is modality specific, while spatial WM as well as object-location binding relies on modality general
processes. 相似文献
12.
Bridget Clarke 《Ethical Theory and Moral Practice》2010,13(3):273-291
One of the most prominent strands in contemporary work on the virtues consists in the attempt to develop a distinctive—and
compelling—account of practical reason on the basis of Aristotle’s ethics. In response to this project, several eminent critics
have argued that the Aristotelian account encourages a dismissive attitude toward moral disagreement. Given the importance
of developing a mature response to disagreement, the criticism is devastating if true. I examine this line of criticism closely,
first elucidating the features of the Aristotelian account that motivate it, and then identifying two further features of
the account that the criticism overlooks. These further features show the criticism to be entirely unwarranted. Once these
features are acknowledged, a more promising line of criticism suggests itself—namely, that the Aristotelian account does too
little to help us to resolve disputes—but that line of objection will have to be carried out on quite different grounds. 相似文献
13.
Featural representations of similarity data assume that people represent stimuli in terms of a set of discrete properties.
In this article, we consider the differences in featural representations that arise from making four different assumptions
about how similarity is measured. Three of these similarity models— the common features model, the distinctive features model,
and Tversky’s seminal contrast model—have been considered previously. The other model is new and modifies the contrast model
by assuming that each individual feature only ever acts as a common or distinctive feature. Each of the four models is tested
on previously examined similarity data, relating to kinship terms, and on a new data set, relating to faces. In fitting the
models, we have used the geometric complexity criterion to balance the competing demands of data-fit and model complexity.
The results show that both common and distinctive features are important for stimulus representation, and we argue that the
modified contrast model combines these two components in a more effective and interpretable way than Tversky’s original formulation. 相似文献
14.
In a number of recent papers Duncan Pritchard argues that virtue epistemology’s central ability condition—one knows that p
if and only if one has attained cognitive success (true belief) because of the exercise of intellectual ability—is neither
necessary nor sufficient for knowledge. This paper discusses and dismisses a number of responses to Pritchard’s objections
and develops a new way of defending virtue epistemology against them. 相似文献
15.
Van Zandt T 《Psychonomic bulletin & review》2000,7(3):424-465
Among the most valuable tools in behavioral science is statistically fitting mathematical models of cognition to data—response
time distributions, in particular. However, techniques for fitting distributions vary widely, and little is known about the
efficacy of different techniques. In this article, we assess several fitting techniques by simulating six widely cited models
of response time and using the fitting procedures to recover model parameters. The techniques include the maximization of
likelihood and least squares fits of the theoretical distributions to different empirical estimates of the simulated distributions.
A running example is used to illustrate the different estimation and fitting procedures. The simulation studies reveal that
empirical density estimates are biased even for very large sample sizes. Some fitting techniques yield more accurate and less
variable parameter estimates than do others. Methods that involve least squares fits to density estimates generally yield
very poor parameter estimates. 相似文献
16.
Formulas are derived by which, given the factor loadings and the internal reliability of a test of unit length, the following estimates can be made: (1) the common-factor loadings for a similar (homogeneous) test of lengthn; (2) the number of times (n) that a test needs to be lengthened homogeneously to achieve a factor loading of a desired magnitude; and (3) the correlation between two tests, either or both of which have been altered in length, as a function of (a) the new factor loadings in the altered tests or (b) the original loadings in the unit-length tests. The appropriate use of the derived formulas depends upon the fulfillment of four assumptions enumerated.This article is based on a paper read by the authors at the annual meeting of the Western Psychological Association in Eugene, Oregon, June 25, 1949. 相似文献
17.
The quality of approximations to first and second order moments (e.g., statistics like means, variances, regression coefficients) based on latent ability estimates is being discussed. The ability estimates are obtained using either the Rasch, or the two-parameter logistic model. Straightforward use of such statistics to make inferences with respect to true latent ability is not recommended, unless we account for the fact that the basic quantities are estimates. In this paper true score theory is used to account for the latter; the counterpart of observed/true score being estimated/true latent ability. It is shown that statistics based on the true score theory are virtually unbiased if the number of items presented to each examinee is larger than fifteen. Three types of estimators are compared: maximum likelihood, weighted maximum likelihood, and Bayes modal. Furthermore, the (dis)advantages of the true score method and direct modeling of latent ability is discussed. 相似文献
18.
Melvin Fitting 《Studia Logica》2009,91(3):335-366
This is a largely expository paper in which the following simple idea is pursued. Take the truth value of a formula to be
the set of agents that accept the formula as true. This means we work with an arbitrary (finite) Boolean algebra as the truth
value space. When this is properly formalized, complete modal tableau systems exist, and there are natural versions of bisimulations
that behave well from an algebraic point of view. There remain significant problems concerning the proper formalization, in
this context, of natural language statements, particularly those involving negative knowledge and common knowledge. A case
study is presented which brings these problems to the fore. None of the basic material presented here is new to this paper—all
has appeared in several papers over many years, by the present author and by others. Much of the development in the literature
is more general than here—we have confined things to the Boolean case for simplicity and clarity. Most proofs are omitted,
but several of the examples are new. The main virtue of the present paper is its coherent presentation of a systematic point
of view—identify the truth value of a formula with the set of those who say the formula is true. 相似文献
19.
Nancy Cartwright (1983, 1999) argues that (1) the fundamental laws of physics are true when and only when appropriate ceteris paribus modifiers are attached and that (2) ceteris paribus modifiers describe conditions that are almost never satisfied. She concludes that when the fundamental laws of physics are
true, they don't apply in the real world, but only in highly idealized counterfactual situations. In this paper, we argue
that (1) and (2) together with an assumption about contraposition entail the opposite conclusion — that the fundamental laws
of physics do apply in the real world. Cartwright extracts from her thesis about the inapplicability of fundamental laws the conclusion
that they cannot figure in covering-law explanations. We construct a different argument for a related conclusion — that forward-directed
idealized dynamical laws cannot provide covering-law explanations that are causal. This argument is neutral on whether the
assumption about contraposition is true. We then discuss Cartwright's simulacrum account of explanation, which seeks to describe
how idealized laws can be explanatory.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
20.
Killeen PR 《Psychonomic bulletin & review》2006,13(4):549-562
Traditional null hypothesis significance testing does not yield the probability of the null or its alternative and, therefore,
cannot logically ground scientific decisions. The decision theory proposed here calculates the expected utility of an effect
on the basis of (1) the probability of replicating it and (2) a utility function on its size. It takes significance tests—which
place all value on the replicability of an effect and none on its magnitude—as a special case, one in which the cost of a
false positive is revealed to be an order of magnitude greater than the value of a true positive. More realistic utility functions
credit both replicability and effect size, integrating them for a single index of merit. The analysis incorporates opportunity
cost and is consistent with alternate measures of effect size, such as r2 and information transmission, and with Bayesian
model selection criteria. An alternate formulation is functionally equivalent to the formal theory, transparent, and easy
to compute. 相似文献