Role saliency cues and children's sentence comprehension

Forty-eight children at four age levels (3, 4, 5, and 7 years) acted out active and passive sentences immediately after exposure to matching information, mismatching information, and no-information cues. The matching information cues yielded the highest comprehension scores, followed in order by the no-information and the mismatching information cues. Active sentences were easier to comprehend than passive sentences, and comprehension scores improved with age. Processing context information in the form of role saliency cues is a component of children's language comprehension and development. It was found that context is used differentially depending on age and linguistic knowledge. The results indicated that the analysis of children's comprehension skills is a multifaceted process not solely dependent upon syntactic processing.This research is in part a revision of a dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Kent State University, Kent, Ohio. A summarized version was presented at the Annual Convention of the American Speech and Hearing Association, San Francisco, 1978.     

Concurrent schedule assessment of food preference in cows

Six dairy cows (Bos taurus) were trained on several pairs of concurrent variable-interval schedules with different types of food available on each alternative. The required response was a plate press made by the animal's muzzle. Performance generally replicated that found with other species. The generalized matching law accounted for the preference data, showing that food preference could be quantitatively analyzed as a special case of response bias. The preference functions showed that the response- and time-allocation ratios were not as extreme as obtained reinforcement rate ratios (undermatching).     

Children at risk for delinquency: A follow-up comparison of aggressive children and children who steal

This study compared the follow-up incidence of court-recorded nonstatus offenses for three groups of adolescent children. These children had been seen 2 to 9 years earlier for problems with aggression in the home (N = 21), for stealing problems (N = 25), or for normative comparisons (N = 14). The results showed that 77% of the children with stealing problems had court-recorded offenses. This was significantly higher than the aggressive children, whose rate did not differ from the normative sample. These findings suggested that young aggressive children were not at risk for adolescent court contact. Instead, it was the young child with identified stealing problems who was highly likely to become an official delinquent. It also appeared that parental reports of stealing events constituted a predictive measure of later criminal acts.     

EFFECTS OF DIRECT,INTERMITTENT, AND VICARIOUS REINFORCEMENT PROCEDURES ON THE DEVELOPMENT AND MAINTENANCE OF INSTRUCTION-FOLLOWING BEHAVIORS IN A GROUP OF YOUNG CHILDREN1

A group of young children (mean age: 2.5 yr) were instructed to follow different requests by a teacher in a day-care setting. Experiment I verified that mean group instruction following was low (10%) despite the opportunity for “observational learning”, i.e., the group of 12 children could watch a nonreinforced adult comply with the teacher's request. In Experiment II, when positive consequences were provided contingent on the adult model's behavior, mean group instruction following was relatively unaffected (14%). When direct reinforcement was given to four peer models, each for several sessions, the individual performances of three of the four peer models was elevated (from 50% to 80%); however, the mean performance of the remaining nonreinforced children (N = 7) was only moderately affected (21%). When reinforcement contingencies were again changed, so that each group member was provided direct, but intermittent reinforcement, mean group performance increased substantially to levels of over 70%. Once instruction following was high, presentation of reinforcement only to one peer model sufficed to maintain performance whereas earlier, this same vicarious reinforcement procedure had failed to establish group compliance. The maintenance of instruction-following behavior when reinforcement was applied solely to one child was interpreted mainly in terms of a high resistance to extinction following a history of intermittent reinforcement rather than a “vicarious”- or “self”-reinforcement mechanism. Finally, removal and re-introduction of group intermittent reinforcement, respectively, lowered performance (to levels of 40%) and elevated (to levels of 65%) the group's performance.     

Discrimination learning and stimulus generalization by impulsive and reflective children

The proposition that impulsive children inhibit expressive behavior less than reflective children was investigated by providing third grade impulsive and reflective boys with either differential or nondifferential forms or successive discrimination training prior to tests for stimulus generalization. Consistent with specific predictions derived from Spence's theory on the roles of excitation and inhibition, it was found that: (a) Reflectives acquired the discrimination more rapidly, (b) reflectives achieved a higher level of discriminative performance, (c) impulsives exhibited more variable response reates during the nonreinforced stimulus, and (d) the type of training interacted with the child's conceptual tempo to determine the elevation and shape of the post-discrimination generalization gradients. The results provide support for the construct validity of the Matching Familiar Figures Test of reflectivity-impulsivity.     

Normative location theory: Placement in continuous space

This paper selectively reviews an area of operations research, refered to as normative location theory, that deals with the placement of objects in continuous space. The computational procedures discussed in this literature require initially that a certain set objects be located a priori; the placement of the objects in a second set is then determined in such a way that the total “interaction” among the fixed and variable objects is minimized. A number of strategies appropriate for different distance functions are surveyed and a numerical example is given illustrating one particular iterative algorithm. Although the current versions of these location methods depend upon more than the nonmetric information contained in the proximity measures defined for all pairs of objects, they can be generalized, and consequently, several possible connections to nonmetric multidimensional scaling are pointed out.