On the {↔, ∼} -reduct of the intuitionistic consequence operation

The intuitionistic consequence operation restricted to the language with (equivalence) and (negation) as the only connectives is axiomatized by means of a finite set of sequential rules of inference.To the memory of Professor Roman Suszko     

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.     

Discrete dynamic choice: An extension of the choice models of thurstone and luce

The present paper deals with the extension of two well-known static discrete choice theories to the dynamic situation in which individuals make choices at several points in (continuous) time. A dynamic version of Luce's Axiom, “independence from irrelevant alternatives”, is proposed and some of its implications are derived. In the static case Yellott (J. Math. Psych. 1977, 15, 109–146) and others have demonstrated that an independent random utility model generated from the extreme value distribution exp(?e^?ax?b) becomes equivalent to Luce's Axiom. Yellott also introduced an axiom called “invariance under uniform expansions of the choice set”, and he proved that within the class of random utility models with independent identically distributed utilities (apart from a location shift) this axiom is equivalent to Luce's Axiom. These results are extended to the dynamic situation and it is shown that if the utility processes are expressed by so-called extremal processes the corresponding choice model is Markovian. A nonstationary generalization is proposed which is a substantial interest in applications where the parameters of the choice process are influenced by previous choice experience or by time-varying exogenous variables. In particular, it is demonstrated that the nonstationary model is Markovian if and only if the joint choice probabilities at two points in time have a particular form. Thus, the paper provides a rationale for applying a specific class of Markov models as the point of departure when modelling mobility processes that involve individual discrete decisions over time.     

The effects of distributed training on retention of operant conditioning in human infants

Long-term retention of operant footkicking acquired in the mobile conjugate reinforcement paradigm was assessed as a function of the distribution of training time. In the first study, 3-month-old infants were trained for either one 18-min session or for two 9-min or three 6-min sessions separated by 24-hr intervals. All infants exhibited retention during a test administered immediately after training, but only those trained in a single session continued to perform the conditioned response during cued-recall tests 7 or 14 days later. Infants trained in three sessions showed no evidence of remembering the contingency even after a week. A warm-up decrement, seen in the day-to-day performance of infants in the distributed conditions, was eliminated in the second study by the interpolation of a nonreinforcement period at the outset of daily sessions. This procedure also enhanced long-term retention such that infants trained in three 6-min session now remembered the contingency for 14 days and did not differ from infants who had received a single 18-min session. Whether distributed training facilitates or impairs long-term retention appears to depend on the opportunity for infants to acquire a sufficient number (or kind) of effective retrieval cues during original learning.     

Spatial representations of young children: the role of self- versus adult-directed movement and viewing

The influence of the control of movement and viewing while exploring a novel large-scale environment was assessed. Forty kindergarteners and forty second grade children served in four activity conditions that represented the factorial combination of movement (self vs adult directed) and viewing (self vs adult directed). A significant grade level X movement X viewing interaction revealed that when kindergarteners directed their own movement, estimates of interlocation distances were equivalent whether viewing was self or adult directed. If movement was directed by an adult, kindergarteners estimated interlocation distances more accurately if the adult also directed their viewing than if the children directed their own viewing. Second grade children performed comparably across all four experimental conditions.     

Variations of the Bender-Gestalt Test: implications for training and practice

Although the Bender-Gestalt Visual Motor Test has been a popular and influential clinical assessment instrument for the last half century, authoritative opinion and a substantial research literature are often inconsistent or contradictory. This paper documents variations in designs, administration procedures, forms, and applications to particular populations. A careful review of scoring systems indicates the current status of objective approaches as contrasted with interpretation that is global, intuitive, and subjective. Some implications of these variations and interpretive procedures for training and assessment practice are discussed. The major conclusions of the review are summarized in seven points.     

Diagnostic validity of the MMPI and two short forms

The ability of the Faschingbauer Abbreviated MMPI (FAM) and the MMPI-168 to substitute for the full Minnesota Multiphasic Personality Inventory (MMPI) in broad psychiatric diagnosis was examined in a sample of 514 psychiatric inpatients. Each sex was randomly divided and multiple discriminant functions derived using long form scales as predictors. The discriminant functions were cross-validated on the other same-sex group using long and short form scales as predictors. All three forms achieved a 46% "hit" rate overall. No significant differences among the three forms were found.     

A review of projective test findings with older adults

The projective test literature on aging is reviewed. It was concluded that, while much critical research remains to be done and many of the studies are flawed, projective testing has contributed a great deal to the understanding of the aging process and has yielded a core of consistent findings. Suggestions for future research which would help resolve some current ambiguities were made.     

Response rate, latency, and resistance to change

Pigeons were trained on a multiple variable-interval/variable-interval schedule with pacing contingencies that generated high response rates in one component and low response rates in the other. Timeout periods separated the schedule components. During resistance-to-change tests, response-independent food was presented during the timeout periods, and the duration of that food presentation was varied among test sessions. Response rates in the schedule components decreased and latencies to the first response increased as a function of the duration of food presentations during the timeout. Both dependent measures changed about the same amount relative to their own baseline levels. The conclusions are that baseline response rates controlled by pacing contingencies are equally resistant to change, given equal reinforcement densities, and latency is a sensitive measure of resistance to change.