Metric and nonmetric plotting models

A problem with standard printer scatterplot routines is that points are not adequately labeled. Four methods of generating printer plots are presented. All four methods allow multi-character point labels, and three of the methods can guarantee that no portion of the labels are hidden. This is accomplished by using varying amounts of metric and nonmetric distance information to locate the points.The author wishes to thank Warren Sarle and Forrest Young who provided many valuable suggestions during the development of PROC IDPLOT.The methods and procedure described in this paper were developed by the author at the University of North Carolina as a part of a software development project funded by SAS Institute Inc.     

Influence of two types of information trials on the formation of a discrimination-reversal learning set in Japanese monkeys

Abstract: Three groups of male adult Japanese monkeys were trained in 30 discrimination-reversal learning-set (LS) problems using the Wisconsin General Test Apparatus. A control group ( N = 3) was trained in the standard procedure: acquisition of up to 12 consecutive correct responses, reversal to the same criterion, and then shift to a new problem. To the other two groups, three information trials signaling the stimulus value in reversal were given after they reached the criterion in acquisition. Subjects in the positive-stimulus information (PSI) group ( N = 4) were exposed only to the reversal positive stimulus, and a response to it was rewarded. Subjects in the negative-stimulus information (NSI) group ( N = 4) were exposed only to the reversal negative stimulus, and any response to it was not rewarded. Information trials reduced reversal errors and NSI trials were more effective than PSI trials in error reduction ( p < .05). Information trials also aided in acquisition: the NSI and PSI groups learned the acquisition phase of the problems with significantly fewer errors than control group ( p < .01) in the last stage of training. The implications of these results are discussed in relation to strategy learning and attention learning in LS formation.     

Relax and try this instead: abbreviated habit reversal for maladaptive self-biting.

We evaluated the effectiveness of an abbreviated habit reversal procedure to reduce mal-adaptive oral self-biting in an adolescent boy in residential care. Treatment involved a combination of relaxation and two competing responses. Results of a withdrawal design and two posttreatment medical evaluations indicated that the intervention eliminated the biting and the tissue damage it caused.     

MODIFYING LETTER AND NUMBER REVERSALS IN ELEMENTARY SCHOOL CHILDREN1

Children from regular and special-education classes were exposed to tutoring procedures designed to modify letter and number reversals. In Experiment I, two students showed reversals during letter-naming (e.g., saying p for q) and two-digit number (e.g., writing 31 for 13) exercises. In Experiment II, one subject made two-digit reversals, while the other child reversed single-digit numbers (e.g., 9 written with circle on right side of stem). The subject in Experiment III emitted letter reversals under naming, dictation, and copying exercises. The child in Experiment IV showed written letter reversals on both sides of the “body midline” under dictation procedures. Basic treatment procedures during all experiments involved modelling of correct and incorrect symbol formation, and differential experimenter feedback following student responses. During Experiments I and II, subjects were praised for each correct response, and informed when a reversal occurred. Experiment III included a Modelling Only Phase before these feedback procedures. Besides praise, treatment conditions in Experiment IV consisted of additional feedback following correct responses (e.g., charting correct responses), and temporal delays imposed between dictated letters and student responses. Except for occasional letter-naming reversals of one subject (Experiment I), and letter dictation errors of another (Experiment IV), reversals were eliminated when all experiments terminated. The Modelling Only Phase in Experiment III also reduced reversals to a low level. These findings suggest that a variety of reversal problems may be effectively assessed and remediated via simple modelling and reinforcement procedures. In addition, postcheck observations indicated that the effects were enduring. The present procedures should be easily implemented by school personnel.     

A note on multiple and canonical correlation for a singular covariance matrix

A weaker generalized inverse (Rao's g-inverse; Graybill's c-inverse) can be used in place of the Moore-Penrose generalized inverse to obtain multiple and canonical correlations from singular covariance matrices.The author expresses his gratitude to a referee for his suggestions.     

A note on monotone polygons fitted to bivariate data

The monotone regression function of Kruskal and the rank image function of Guttman and Lingoes were fitted to bivariate normal samples and their statistical properties contrasted.This paper was written while the author was a Visiting Professor in the Department of Psychology, University College, London.     

Sensitivity to reinforcer duration in a self-control procedure

In a concurrent-chains procedure, pigeons' responses on left and right keys were followed by reinforcers of different durations at different delays following the choice responses. Three pairs of reinforcer delays were arranged in each session, and reinforcer durations were varied over conditions. In Experiment 1 reinforcer delays were unequal, and in Experiment 2 reinforcer delays were equal. In Experiment 1 preference reversal was demonstrated in that an immediate short reinforcer was chosen more frequently than a longer reinforcer delayed 6 s from the choice, whereas the longer reinforcer was chosen more frequently when delays to both reinforcers were lengthened. In both experiments, choice responding was more sensitive to variations in reinforcer duration at overall longer reinforcer delays than at overall shorter reinforcer delays, independently of whether fixed-interval or variable-interval schedules were arranged in the choice phase. We concluded that preference reversal results from a change in sensitivity of choice responding to ratios of reinforcer duration as the delays to both reinforcers are lengthened.     

Weighted minimum trace factor analysis

In the last decade several authors discussed the so-called minimum trace factor analysis (MTFA), which provides the greatest lower bound (g.l.b.) to reliability. However, the MTFA fails to be scale free. In this paper we propose to solve the scale problem by maximization of the g.l.b. as the function of weights. Closely related to the primal problem of the g.l.b. maximization is the dual problem. We investigate the primal and dual problems utilizing convex analysis techniques. The asymptotic distribution of the maximal g.l.b. is obtained provided the population covariance matrix satisfies sone uniqueness and regularity assumptions. Finally we outline computational algorithms and consider numerical examples.I wish to express my gratitude to Dr. A. Melkman for the idea of theorem 3.3.     

Positional Goods and the Social Rank Hypothesis: Income Inequality Affects Online Chatter about High‐ and Low‐Status Brands on Twitter

According to a social rank hypothesis, consumers who live in regions with higher income inequality will show greater interest in, and attention toward, positional goods and high‐status brands that serve a social signaling role. We analyze millions of posts on the microblogging platform Twitter for mentions of high‐ and low‐status brands. We find that luxury brands such as “Louis Vuitton” and “Rolex” are more frequently mentioned in tweets originating from US states, counties, and major metropolitan areas with higher levels of income inequality. In contrast, mentions of everyday brands such as “Walmart” or “Kmart” are more frequent in regions with a more equal distribution of income. Using sentiment analysis, we find higher valence (positivity) and arousal (excitement) for tweets that both mention high‐status brands and originate from regions with high levels of income inequality. These results corroborate the social rank hypothesis, showing that more psychological resources are allocated to positional consumption when the income gap between the rich and the poor is larger.     

Patterns of emotional availability between mothers and young children: Associations with risk factors for borderline personality disorder

Emotional availability (EA) characterizes a warm, close relationship between caregiver and child. We compared patterns (clusters) of EA on risk factors, including those for borderline personality disorder (BPD). We sampled 70 children aged 4 to 7 years from low socio‐economic backgrounds: 51% of whose mothers had BPD. We coded filmed interactions for EA: mothers' sensitivity, structuring, non‐intrusiveness, non‐hostility, and children's responsiveness to, and involvement of, mothers. We additionally coded children's over‐responsiveness and over‐involvement. Using person‐centred analyses, we identified four clusters: high functioning, low functioning, asynchronous (mothers above average on two of four dimensions and children below), and below average. Mothers in the low‐functioning cluster had lower income, less social support, more of the borderline feature of negative relationships, and more depression than did mothers in the high‐functioning cluster. The children in the low‐functioning group had more risk factors for BPD (physical abuse, neglect, and separation from, or loss of caregivers, and negative narrative representations of the mother–child relationship in their stories) than did children in the high‐functioning group. The asynchronous group included older girls who were over‐responsive and over‐involving with their mothers in an apparent role reversal. Interventions targeting emotional availability may provide a buffer for children facing cumulative risks and help prevent psychopathology.

Highlights

• This paper investigated how mother‐child emotional availability (warmth and closeness) relates to risk factors for borderline personality disorder, including mother‐child role reversal.
• In filmed mother‐child interactions, low emotional availability was associated with risk for borderline personality disorder and role reversal was more likely for older girls.
• Findings support the cumulative risk hypothesis and may inform interventions to improve mother‐child emotional availability to prevent the development of psychopathology.