Concurrent validity of the WISC-R factor scores

This study investigated the efficacy of predicting academic achievement as measured by the Wide Range Achievement Test using the factor scores of the Wechsler Intelligence Scale for Children-Revised as potential predictors. Both instruments were administered to 200 school children referred for psychological evaluations. Factor scores for the WISC-R were computed according to equations provided by Gutkin (1978). These factor scores then were regressed in a stepwise manner on the Reading, Spelling, and Arithmetic standard scores from the Wide Range Achievement Test. Stepwise regressions also were performed using the traditional Verbal and Performance IQs as the potential predictors. A comparison was made between the results obtained by use of the factors or the more common scores. The results indicated that the Freedom From Distractibility factor score significantly aided in the prediction of Reading and Spelling achievement and was of primary importance in predicting Arithmetic achievement. When the stepwise results using the different scores were contrasted, the factor scores accounted for appreaciably more variance in Arithmetic than did the traditional Verbal and Performance IQs. Derived regression equations are reported along with a discussion of the interpretability of the Freedom From Distractibility factor.     

The fallacy of “two years below grade level for age” as a diagnostic criterion for reading disorders

The use of grade equivalent scores contrasted against grade placement is widespread in the diagnosis of dyslexia and other reading disabilities. This method substantially overstates disabilities at upper grade levels while underestimating the severity of difficulties in the early grades. Other difficulties and difficulties and distortions of this methods are also pointed out. An accurate, alternative method for reliably determining aptitude/achievement discrepancies is presented and its use discussed.     

Spontaneous configuring to a tone-light compound using appetitive training

Rats were trained to bar-press for water in the presence of a simultaneous compound tone-light stimulus using a discrete-trial procedure. Different groups were given between 300 and 3900 trials. When subsequently tested in extinction, all rats showed consistent levels of responding to the compound stimulus but responding to the tone and light components declined as a function of number of training trials. This is a demonstration of spontaneous configuring. Two other experiments showed that with similar procedures generalization from a component of the training stimulus to other values on the same continuum decreases with increased training with the compound stimulus. It was concluded that configuring and generalization from a single stimulus involve the same processes.     

Context, categorization, and recall: The “change-of-standard” effect

A psycholinguistically based conception of the relation among context, categorization, and memory is tested by examining what happens to people's memory of an object when the object is initially categorized in terms of the context in which it appears, but, when the object is later recalled, this context is no longer salient. Subjects read about the sentencing decisions of a target trial judge in the context of other trial judges who consistently gave either higher sentences or lower sentences than the target judge. As predicted, subjects tended to categorize the target judge as “lenient” in the former, harsh context condition, and as “harsh” in the latter, lenient context condition. A week later, subjects read about the sentencing decisions of some additional judges, and then recalled the sentencing decisions of the target judge they had read about the week before. Across the two sessions, either a harsh, moderate, or lenient category norm for judges' sentencing decisions was established by having subjects read about decisions that involved either high, medium, or low sentences, respectively. The results indicated that subjects recalled the target judge's decisions by interpreting their prior categorization of his behavior in terms of the category norm established across the two sessions rather than the original context. Thus, subjects who were exposed to the same target in the same circumstances, and initially categorized the target in the same way, nevertheless remembered his behavior differently if their category norm was different at the moment of recall. Other types of “change of standard” and their implications for human judgment and memory are discussed.     

The development of discourse mapping processes: the on-line interpretation of anaphoric expressions

The present research focuses on how children integrate the antecedent of different kinds of anaphor into their on-going interpretation of an utterance, and on the kinds of cues they use to help them to do this. These issues were studied by examining the on-line processing of three types of anaphoric devices—repeated noun phrases, general terms and pronoun anaphors. The data showed that by the age of five, anaphoric mapping processes in general are well-mastered, although all age-groups (5, 7, 10 year olds and adults) found general term anaphors more difficult to interpret. The major developmental differences concerned the processing of anaphoric pronouns. For five year olds, pronouns were primarily interpreted as devices which maintained the thematic subject of the discourse, but when there was no thematic subject they relied primarily on pragmatic plausibility in their assignment of pronominal co-reference. As children get older, they are able to take advantage of the lexical properties of pronouns and all three sources of information—lexical, pragmatic inference and the thematic structure of the discourse—play contributory roles in the assignment of reference to a pronoun.     

Some theory and results for metrics for bounded response scales

In an earlier note, a new metric for bounded response scales (MBR) was introduced which resembles the city-block metric but is bounded above. It was suggested the MBR may be more appropriate than minkowski metrics for data obtained with bounded response scales. In this article, some formal properties of the MBR are investigated and it is shown that it is indeed a metric. Empirical predictions are then derived from the MBR and contrasted with those of a “monotonicity hypothesis,” which holds that dissimilarity judgements tend to be biased towards overestimation of larger distances, and with the predictions of the minkowski metrics, which imply additivity of collinear segments. Some empirical results are presented which contradict the monotonicity hypothesis and the minkowski metrics, and favor the MBR. Finally, the logic used to motivate the MBR is invoked to define a subadditive concatenation for bounded norms in the one-dimensional case, which may be useful in psychophysical work where the upper bounds are often real, rather than due to the response scale. This concatenation predicts understimation for doubling and overestimation for halving and middling tasks.     

A procedural theory of eye movements in doing arithmetic

A procedural theory of eye movement that accounts for main features of the stochastic behavior of eye-fixation durations and direction of movement of saccades in the process of solving arithmetic exercises of addition and subtraction is presented. The best-fitting distribution of fixation durations with a relatively simple theoretical justification consists of a mixture of an exponential distribution and the convolution of two exponential distributions. The eye movements themselves were found to approximate a random walk that fits rather closely in both adult and juvenile subjects the motion postulated by the normative algorithm ordinarily taught in schools. Certain structural features of addition and subtraction exercises, such as the number of columns, the presence or absence of a carry or a borrow, are well known to affect their difficulty. In this study, regressions on such structural variables were found to account for only a relatively small part of the variation in eye-fixation durations.     

Some deterministic models of concept identification

It is shown that deterministic models can compete effectively with stochastic models in summarizing concept identification behavior. Three groups of deterministic models are examined. Examination of individual learners' trial by trial behavior in a concept experiment shows: (1) One person exhibited behavior consistent with a Hypothesis Permutation (HP) model despite being a nonlearner who showed no evidence of improvement over a period of 24 trials. However, when all 50 persons studied in each of two treatment groups were examined, only 22 members of one group and 10 of the other showed no inconsistencies with deterministic local consistency assumptions. (2) Certain deterministic computer programs could find at least one satisfactory order for predicting all responses by 18 of the 22 consistent solvers and 6 of the 10 consistent solvers, respectively, in the two groups just mentioned. For these 24 persons, then, a less restrictive deterministic model is adequate than for the others. (3) Those 38 original members of the first treatment group who met a stringent learning criterion were compared with respect to predictions generated by stochastic and mathematized deterministic models. One deterministic model (RSS-U 9-state) is in some respects the best of the models examined, but this success is a partial reflection of estimating eight parameters from the data.     

An axiomatization of the ratio/difference representation

If ≥_r and ≥_d are two quaternary relations on an arbitrary set A, a ratio/difference representation for ≥_r and ≥_d is defined to be a function f that represents ≥_r as an ordering of numerical ratios and ≥_d as an ordering of numerical differences. Krantz, Luce, Suppes and Tversky (1971, Foundations of Measurement. New York, Academic Press) proposed an axiomatization of the ratio/difference representation, but their axiomatization contains an error. After describing a counterexample to their axiomatization, Theorem 1 of the present article shows that it actually implies a weaker result: if ≥_r and ≥_d are two quaternary retations satisfying the axiomatization proposed by Krantz et al. (1971), and if ≥_r′ and ≥_d′ are the relations that are inverse to ≥_r and ≥_d, respectively, then either there exists a ratio/difference representation for ≥_r and ≥_d, or there exists a ratio/difference representation for ≥_r′ and ≥_d′, but not both. Theorem 2 identifies a new condition which, when added to the axioms of Krantz et al. (1971), yields the existence of a ratio/difference representation for relations ≥_r and ≥_d.