L'avenir de l'approche par élaboration de règles

The goal of this study is the elaboration of a computerized diagnostic instrument based on Siegler's rule-assessment approach for assessing the acquisition of the probability quantification scheme in subjects aged 6–18 years. Three versions of the test were used. Version 1 was Siegler's original version (four types of problems and four rules). In version 2 five new rules were added; version 3 contained the five new rules plus eleven types of problems. Results show that version 1 allows the classification of only 50% of subjects; version 2, 60%; and version 3, 70%. Despite improved versions, some weaknesses remain, the most important one being that it is still impossible to evaluate intra-individual variability. Aware of these limits, Siegler has reassigned his model to a local model of problem solving, and suggests a developmental model of information processing inspired by a Darwinian model of variation and strategy selection. The authors hypothesize that computer engineering could not only reaffirm the general status of the rule-assessment approach, but could also allow consideration of intra-individual variability.     

The array size function in simple visual search tasks: A comparison between “go-no go” and “yes-no” tasks under conditions of high and low target-noise similarity

Summary In research on visual search within a single eye-fixation a number of different tasks are used and referred to interchangeably. Research with other types of tasks suggests that there are possibly important differences between these tasks. In the present study, two types of search tasks were compared under conditions as equal as possible: the go-no go task and the yes-no task. Conditions of low and high target-noise similarity were used. The results obtained showed: a) a steeper slope of the array size function in yes-no tasks than in go-no go tasks on the first day of practice but not on the second: b) a higher intercept value of the same function for yes-no tasks than for go-no go tasks; and c) a greater proportion of errors with yes-no tasks than with comparable go-no go tasks. A tentative model, describing the main features of the results obtained, is briefly sketched.     

Kreisel,the continuum hypothesis and second order set theory

Summary The major point of contention among the philosophers and mathematicians who have written about the independence results for the continuum hypothesis (CH) and related questions in set theory has been the question of whether these results give reason to doubt that the independent statements have definite truth values. This paper concerns the views of G. Kreisel, who gives arguments based on second order logic that the CH does have a truth value. The view defended here is that although Kreisel's conclusion is correct, his arguments are unsatisfactory. Later sections of the paper advance a different argument that the independence results do not show lack of truth values.     

The effects of component duration on multiple-schedule performance in closed and open economies.

Pigeons responded on multiple variable-interval variable-interval schedules of reinforcement in an open and a closed economy. Equal duration components were increased in duration while the component rates of reinforcement were held constant, the component schedules were reversed, and component duration was decreased. In the open economy, daily sessions were limited to 1 hr, and subjects were maintained at 80% of their free-feeding weights through supplemental feeding when necessary in their home cages. In the closed economy, subjects were housed in their experimental chambers and no deprivation regimen was enforced. Relative response rate decreased as components were lengthened in the open economy, whereas in the closed economy relative rate increased as components were lengthened. Response proportions overmatched reinforcer proportions to a greater extent at long component durations in the closed economy, but there was no systematic effect of component duration on responding in the open economy.     

Effect of mouth opening on bite-force discrimination

The purpose of this study was to determine whether different extents of mouth opening affect normal subjects' (N = 24; 12 women, 12 men) ability to discriminate differences in their interincisor bite force. Three mouth openings were selected including 50, 70, and 90 percent of maximum opening for each subject. Bite force was measured using a specially designed strain gauge scale which permitted subjects to monitor visually when their biting force equalled a preset resistance. Resistance forces of 500 and 1000 gm. were selected as standards. The procedure involved the use of a modified method of constant stimuli in which each subject was presented with a series of paired resistance settings, one at a time--the first resistance setting being the standard and the second resistance was the comparator. This paired-comparisons procedure was continued until the subjects' difference limen (DL) value (the threshold of discrimination between two forces) could be established. An analysis of variance yielded no significant differences in subjects' ability to discriminate bite force as a function of mouth opening.     

Mixed-Design Training Outcomes for Fellows Serving At-Risk Youth Within Integrated Care Settings

We used an exploratory mixed-methods design with single-case comparative analysis and analysis of covariance to evaluate the potential effectiveness of an interprofessional clinical training in a mental health counseling program. Initial findings indicate those engaging in specialized learning experiences that attended to critical aspects of youth behavioral health care experienced benefits with regard to their professional development, interprofessional socialization and valuing, and counseling self-efficacy. Implications for the usefulness of trainings focused on interprofessional experiences are framed in relation to professional trends concerning integrated health care.