Robust estimation of ability in the Rasch model

Estimating ability parameters in latent trait models in general, and in the Rasch model in particular is almost always hampered by noise in the data. This noise can be caused by guessing, inattention to easy questions, and other factors which are unrelated to ability. In this study several alternative formulations which attempt to deal with these problems without a reparameterization are tested through a Monte Carlo simulation. It was found that although no one of the tested schemes is uniformly superior to all others, a modified jackknife stood out as the best one in general, it was also super efficient (more efficient than the asymptotically optimal estimator) for tests with forty or fewer items. It is proposed that this sort of jackknifing scheme for estimating ability be considered for practical work.This research was funded through a grant from the Law Enforcement Assistance Administration (78-NI-AX-0047) to the Bureau of Social Science Research, Howard Wainer, Principal Investigator. We would like to thank Ronald Mead, Anne Morgan and James Ramsay for kind, generous, and invaluable help at various stages of the project.     

Processing of information about location during locomotion: Effects of a concurrent task and locomotion patterns

How maintenance of orientation during locomotion in unfamiliar environments is accomplished was investigated by having subjects walk behind a moving light line (1.12 m/sec) in a dark room and, from a stopping point, numerically estimate direction and distance to the starting point. Two linear distances (5.0–8.4 m) and the angle of direction change (45, 90, and 135 deg) were orthogonally varied as 12 locomotion patterns. Eight high-school students were assigned to each of three conditions, two in which the starting point was invisible, one in which it was visible. In one of the former conditions the subjects counted backwards rapidly during walking. Lower accuracy and longer latency times were found in the counting condition whilst the other two conditions differed only slightly. The results suggested that accurate maintenance of orientation is achieved by recurrent encoding, coordination and decoding of information about direction change and locomotion distance, processes which demand central processing capacity and therefore are interfered with by a concurrent task.     

Psychology and "ordinary language"—a critique of Smedslund

This article takes up methodological issues of the kind raised by Jan Smedslund in earlier issues of this journal, concerning the status of psychological enquiry as a discipline. Arguments are presented which aim to show that Smedslund has failed to establish the thesis that all generally valid theoretical statements in psychology are explications of conceptual relationships embedded in ordinary language, i.e., analytic statements. Some specific examples of what Smedslund takes to be "ordinary language theorems" are examined. Doubts are expressed concerning the validity of the proof procedure Smedslund employs in the "demonstration" of a number of his alleged theorems. Finally, it is argued that the results produced by the situation-bound and culture-bound empirical research of the psychologist need not be viewed as "arbitrary" in Smedslund's sense of that term.     

Finite axiomatization for some intermediate logics

LetN. be the set of all natural numbers (except zero), and letD _n ^* = {k ∈N ∶k|n} ∪ {0} wherek¦n if and only ifn=k.x f or somex∈N. Then, an ordered setD _n ^* = 〈D _n ^* , ? _n , wherex? _ny iffx¦y for anyx, y∈D _n ^* , can easily be seen to be a pseudo-boolean algebra. In [5], V.A. Jankov has proved that the class of algebras {D _n ^* ∶n∈B}, whereB =,{k ∈N∶ ? \(\mathop \exists \limits_{n \in N} \) (n > 1 ≧n ² k)is finitely axiomatizable. The present paper aims at showing that the class of all algebras {D _n ^* ∶n∈B} is also finitely axiomatizable. First, we prove that an intermediate logic defined as follows: $$LD = Cn(INT \cup \{ p_3 \vee [p_3 \to (p_1 \to p_2 ) \vee (p_2 \to p_1 )]\} )$$ finitely approximatizable. Then, defining, after Kripke, a model as a non-empty ordered setH = 〈K, ?〉, and making use of the set of formulas true in this model, we show that any finite strongly compact pseudo-boolean algebra ? is identical with. the set of formulas true in the Kripke modelH _B = 〈P(?), ?〉 (whereP(?) stands for the family of all prime filters in the algebra ?). Furthermore, the concept of a structure of divisors is defined, and the structure is shown to beH D _n ^* = 〈P (D _n ^* ), ?〉for anyn∈N. Finally, it is proved that for any strongly compact pseudo-boolean algebraU satisfying the axiomp ₃∨ [p ₃→(p₁→p₂)∨(p₂→p₁)] there is a structure of divisorsD _* ⁿ such that it is possible to define a strong homomorphism froomiH D _n ^* ontoH D _U . Exploiting, among others, this property, it turns out to be relatively easy to show that \(LD = \mathop \cap \limits_{n \in N} E(\mathfrak{D}_n^* )\) .     

Normative data on the Missouri Children's Picture Series and the Missouri Children's Behavior Checklist with southern black children

Normative data are presented for Southern black children on two objective personality inventories for children: the Missouri Children's Picture Series (MCPS), a child picture-sorting task, and the Missouri Children's Behavior Checklist (MBCL), a parent rating scale. The MCPS was administered to 615 black children attending public schools in a low socioeconomic area of the southeast United States. Parents returned the MBCL on 437 of the children. Means and standard deviations on eight MCPS personality scales and six MCBL behavior rating scales are presented for black males and females at ages 5 through 16, and effects of age, sex, and various scale intercorrelations are discussed. Results suggest systematic age and sex differences on the various scales for black children that are quite atypical when compared with the MCPS in other samples. Various empirical questions regarding the validity of these instruments when used with Southern black children are raised.     

The effect of set size on hemifield asymmetries in letter recognition

Single letters were presented tachistoscopically in the left or right hemifield to right-handed observers. Superior recognition of letters on the right was found for letters chosen from subsets containing four items, but no differences were found when any letter, or any symmetrical letter, could appear. In a second experiment, the right hemifield advantage was found under conditions requiring the subject to determine the subset only when the subset chosen was appropriate. Results were discussed in terms of the adequacy of language-based explanations of hemifield asymmetries in letter recognition.     

Relationship between response to graded exposure and marital satisfaction in agoraphobics

Agoraphobics who were satisfied in their marriage responded well to graded exposure and maintained their improvement to 3-months follow-up. Satisfaction with self and partner remained unchanged in patient and spouse. Agoraphobics who were dissatisfied with their marriage improved initially with graded exposure but later lost most of their gains and reported no change in general neurotic symptoms. Marital dissatisfaction also remained unchanged. Patients' dissatisfaction with their spouses, measured before therapy, predicted outcome in the sample as a whole.