Clustering with relational constraint

The paper deals with clustering problems where grouping is constrained by a symmetric and reflexive relation. For solving clustering problems with relational constraints two methods are adapted: the standard hierarchical clustering procedure based on the Lance and Williams formula, and local optimization procedure, CLUDIA. To illustrate these procedures, clusterings of the European countries are given based on the developmental indicators where the relation is determined by the geographical neighbourhoods of countries.Extended version of the paper presented at the European meeting of the Psychometric Society, Groningen, June, 19–21, 1980.This work was supported in part by the Boris Kidri Fund, Yugoslavia.     

The golden section and an algebraic model of ethical cognition

In experimental investigations related to Kelly's theory of constructs (1955. The psychology of personal constructs. New York: Norton) a special constant was discovered. It was found that subjects on the average choose a positive over a negative pole with the probability 0.62. (Adams-Webber and Benjafield 1973. Canadian Journal of Behavioral Science5, 234–241). The same constant was also found in other experiments related to the choice of elements marked “good” and “bad.” Benjafield and Adams-Webber (1976. British Journal of Psychology67, 11–15) hypothesized that the precise value of this constant coincides with “golden section” ≈0.6180. In this paper it is shown that if we suppose that the subjects actualize mechanisms of choice described by the algebraic model of ethical cognition (which was constructed without any relation to the constant 0.62), then the existence of this constant is mathematically explained. Under very broad assumptions its value is 0.625, and under more constrained conditions it is equal to the golden section ratio precisely.     

Incentive learning following reinforcer devaluation is not conditional upon the motivational state during re-exposure

Three experiments analysed the effect of re-exposure to the reinforcer following aversion conditioning on instrumental performance. In the first experiment, groups of hungry and thirsty rats were trained to press a lever for sucrose, which was then followed by a single injection of lithium chloride (LiCl). On the following day, half the animals in each motivational condition received re-exposure to the sucrose solution; the remaining animals were not re-exposed. In a subsequent extinction test animals that had received re-exposure to the sucrose pressed less than animals that were not re-exposed. Moreover, the effect of re-exposure to the sucrose solution was similar following training under hunger and thirst. In the remaining studies, animals were trained to lever-press for sucrose while either hungry or thirsty. They were then injected with LiCl and re-exposed to the sucrose while either hungry or thirsty, i.e. in the same or different motivational state employed during training, or they were not re-exposed. Lever pressing was then tested in extinction in the training motivational state. As in the first experiment, re-exposure to the reinforcer after aversion conditioning enhanced the magnitude of the reinforcer devaluation effect. More importantly, re-exposure to the sucrose produced a comparable effect on instrumental performance, whether re-exposure was given under the same or different motivational state to that employed during training. These results suggest that the instrumental reinforcer devaluation effect depends upon a process of incentive learning, but that this process is not conditional upon the current motivational state of the animal.     

Counselors’ Mandated Responsibility to Report Child Maltreatment: A Review of U.S. Laws

Although counselors in 44 states are mandatory reporters of child maltreatment, they may lack an understanding of their legally designated role. This article presents the results of a systematic review of child maltreatment reporting laws in all 50 states and the District of Columbia. The authors apply relevant legislation to real‐life contexts for counselors.     

A Comparison of Phonological Awareness Skills in Early French Immersion and English Children

This 2-year study examined the effects of early second language exposure on phonological awareness skills. Syllable, onset-rime and phoneme awareness skills of 72 anglophone children attending English or French immersion programs in primary and grade 1 were investigated. Three-way mixed ANOVAS revealed the following effects and interactions. In terms of grade effect, grade 1 students performed significantly better than primary students on phoneme and onset-rime tasks. A stimulus language effect was observed for the three levels of phonological awareness. All children performed better on English tasks than on French ones. Interaction effects of stimulus language by program were revealed for phoneme as well as syllable tasks. Posthoc analyses revealed that French students performed better on English phoneme and syllable tasks than on French, while English students performed better than French immersion students on French syllable tasks. Correlational analyses revealed significant relationships between reading and phoneme and onset-rime phonological awareness tasks regardless of program of instruction (English, French immersion) or language of reading test (English, French). Syllable awareness was only significantly correlated with the French non-word reading task for the French immersion students.