Problems with bootstrapping pearson correlations in very small bivariate samples

Efron'sMonte Carlo bootstrap algorithm is shown to cause degeneracies in Pearson'sr for sufficiently small samples. Two ways of preventing this problem when programming the bootstrap ofr are considered.     

Favouritism,fairness and joint profit in long-term relationships

This study was designed to test a number of hypotheses about the use of FAV and other strategies as measured by the intergroup ‘matrices’ in four long-term relationships-with spouse, child, friend and workmate. Forty subjects filled in matrices giving three measures of self-favouritism (FAV), and one each of fairness (F) and maximum joint profit (MJP), in relation to the allocation of money and time. It was found that FAV was not used for spouse, and was used less for child than for the non-family relationships (p < 0.01, p < 0.05). There was also an influence of altruism (A) against FAV, when time was distributed between spouse (p < 0.01) or child (p < 0.001) and the self. F was used most for spouse, followed by child, friend and workmate (p < 0.001), and was used more by females in distributing money (p < 0.01). MJP was not used at all for money, but was used to some extent for time.     

PARENT REINFORCEMENT FOR CHILD ACHIEVEMENT: THE USE OF A LOTTERY TO MAXIMIZE PARENT TRAINING EFFECTS

This study describes and evaluates a reinforcement program in which parents earned lottery tickets and won prizes for the progress made by their handicapped children during home-based intervention. An ABAB reversal design replicated across three families was used to assess the effects of the lottery on the children's mastery of language skills. Results showed that the reinforcement of the parents for training accomplishments, as indexed by their children's achievements, produced clinically significant increases in the children's progress when compared with the children's progress under the routine supportive practices of the baseline condition. The implications of the findings for parent training programs in general are discussed.     

Temporal stability and predictive validity of self-assessed hand preference with first and second graders

The test-retest reliability and predictive validity of a five-item hand preference questionnaire (writing, drawing, throwing a baseball, brushing teeth, and cutting with scissors) were investigated in a sample of 80 children attending first and second grade. After 1 month, 81% of the second choices were the same as the first choices. There were interitem differences in the reliabilities of the five items. Writing and drawing hand exhibited the greatest degree of temporal stability. Writing hand was the one task which was significantly related to visual field bias as indexed by a face perception task.     

Validity and temporal stability of the chimeric face technique for studying hemispheric processing asymmetries: Data from 6-through 14-year-old children

The validity and temporal stability of the chimeric face technique as a measure of cerebral hemispheric functioning in children were investigated. The method is based upon the observation that when a subject encounters a representation of the human face, the left side (from the observer's point of view) of the face dominates his or her perception of it. This bias was shown to be present in a majority of children ranging from 6 through 14 years old, and it was stronger for right-handers than for left-handers. The 1-month temporal stability of the bias was 67%, which is comparable to that of other surface methods. As in other split-message techniques, the typical left visual field bias was more reliable than the unusual right visual field bias. The implications of these data are discussed.     

A computer program to synthesize American Sign Language

A program is described that allows experimenters to generate American Sign Language forms by computer. The computer synthesis of such signs could allow major advances in the experimental investigation of the perception of sign language, much as computer-generated speech has done for the study of speech perception.     

Constant errors donot occur in the matched reproduction of angles

MacRae and Loh (1981) reported that when observers attempt to match angles, whether simultaneously or successively, and regardless of whether the angles have the same orientation or not, acute angles generally are set too large and obtuse angles, too small. Without presenting data, they argued indirectly that starting-position effects in their adjustment procedure could not have accounted for the errors. In four experiments, we have demonstrated that effects similar to MacRae and Loh’s do occur when their starting positions are used and that no such effects occur when psychophysical methods that minimize or eradicate starting position effects are used.