Unconditionally Selective Dependence of Random Variables on External Factors

What is the meaning of saying that random variables {X(1), em leader, X(n)} (such as aptitude scores or hypothetical response time components), not necessarily stochastically independent, are selectively influenced respectively by subsets {Gamma(1), em leader, Gamma(n)} of a factor set Phi upon which the joint distribution of {X(1), em leader, X(n)} is known to depend? One possible meaning of this statement, termed conditionally selective influence, is completely characterized in Dzhafarov (1999, Journal of Mathematical Psychology, 43, 123-157). The present paper focuses on another meaning, termed unconditionally selective influence. It occurs when two requirements are met. First, for i=1, em leader, n, the factor subset Gamma(i) is the set of all factors that effectively change the marginal distribution of X(i). Second, if {X(1), em leader, X(n)} are transformed so that all marginal distributions become the same (e.g., standard uniform or standard normal), the transformed variables are representable as well-behaved functions of the corresponding factor subsets {Gamma(1), em leader, Gamma(n)} and of some common set of sources of randomness whose distribution does not depend on any factors. Under the constraint that the factor subsets {Gamma(1), em leader, Gamma(n)} are disjoint, this paper establishes the necessary and sufficient structure of the joint distribution of {X(1), em leader, X(n)} under which they are unconditionally selectively influenced by {Gamma(1), em leader, Gamma(n)}. The unconditionally selective influence has two desirable properties, uniqueness and nestedness: {X(1), em leader, X(n)} cannot be influenced selectively by more than one partition {Gamma(1), em leader, Gamma(n)} of the factor set Phi, and the components of any subvector of {X(1), em leader, X(n)} are selectively influenced by the components of the corresponding subpartition of {Gamma(1), em leader, Gamma(n)}. Copyright 2001 Academic Press.     

Toddlers' use of metric information and landmarks to reorient

Mobile organisms can keep track of spatial location (both their own location and that of objects in the environment) using either an external referent system or one centered on the self and updated by information about movement through space. When the latter system is disabled (e.g., by rapid turning), aspects of the external world must be used to reestablish orientation. Recently, it has been claimed that, both for rats and for human toddlers, reorientation is achieved using a geometric module that accepts only information about the metric properties of the environment (C. R. Gallistel, 1990; L. Hermer & E. S. Spelke, 1994, 1996). In a series of experiments, this paper confirms that geometric information is used for reorientation by young children, but gives reason to doubt that the use of this information is achieved using a module impenetrable to nongeometric information.     

Conceptualization of perceptual attributes: a special case for color?

Young children experience difficulties establishing conceptual representations of color compared with everyday objects. We argue that comparing the development of color cognition to that of familiar objects is inappropriate since color is a perceptual attribute that can be abstracted from an object and by itself lacks functional significance. Instead, we compared the recognition, perceptual saliency, and naming of color to that of three other perceptual object attributes (motion, form, and size) in 47 children aged 2 to 5 years as a function of language age. Results revealed that, although color was perceptually salient relative to the other visual attributes, no selective impairment to color cognition (recognition and naming) was found relative to the three other visual attributes tested. Thus, when the appropriate comparisons are made, we find no special delay in the development of color conceptualization. Furthermore, the striking disparity between perceptual saliency and cognition of color in our youngest age groups suggests that perceptual saliency has little influence on the conceptual development of color.     

The predictive strength of personal constructs versus conventional constructs: self-image disparity and neuroticism

Idiographic personal construct (PC) measures of self-image disparity were hypothesized to be stronger than nonidiographic conventional construct (CC) measures in predicting neuroticism. Ninety-six college students completed PC and CC measures of real self, ideal self, social self, and ideal social self; the NEO Five-Factor Inventory; and the Marlowe-Crowne Social Desirability Scale. Content analysis showed that individuals' PC measures were unique. The disparity between real self and ideal self and the disparity between social self and ideal social self were computed for PC and CC; test-retest reliabilities were .76 to .81. Results of simultaneous multiple regression analyses supported the hypothesis. Also, the two-variable PC self-image disparity scores were stronger than one-variable PC esteem scores in predicting neuroticism. Implications were discussed for research method, self-concept theory, personal construct theory, neuroticism, and psychotherapy.     

Neuroticism and social comparison orientation as moderators of affective responses to social comparison at work

In a study among 72 nurses, the affective consequences of social comparison were examined and related to neuroticism (N) and to social comparison orientation (SCO). Participants were confronted with a bogus interview with an upward versus a downward comparison target. Positive affect and identification were higher, and negative affect was lower, in the upward than in the downward comparison condition. Independent of their SCO, the higher individuals were in N, the less they identified with the upward comparison target, the more they identified with the downward comparison target, and the less positive affect they showed following confrontation with the upward comparison target. In contrast, independent of their level of N, the higher individuals were in SCO, the more negative affect they showed following confrontation with the downward comparison target. The effects on negative affect stayed the same when controlling for positive affect, and the effects on positive affect stayed the same when controlling for negative affect. These effects were also obtained when perceived direction was used as a predictor instead of the experimentally manipulated direction. It is concluded that, although N and SCO are correlated, these variables seem to have independent and distinct effects upon the responses to social comparison information.     

Development of lower extremity kinetics for balance control in infants and young children

Developmental changes in the kinematics and kinetics underlying balance control were studied in 61 children, 9 months to 10 years of age. The children were classified according to developmental milestones as standers; new, intermediate, and advanced walkers; runners-jumpers; hoppers; gallopers; and skippers. The children experienced support-surface translations of varying size and speed. Children with greater locomotor experience withstood larger balance threats without collapsing or stepping. Analyses of scaled trials (perturbations normalized in size to foot length and center of gravity height) revealed that improvement in balance was not related to initial configuration parameters surrounding the task (degree of crouch or lean). Children with advanced locomotor skills had faster recovery times and relatively larger muscle torques than children with less experience. Relative torque-time histories of the more experienced children began to match the adult response to similar perturbations. With increased experience and changing muscle torque regulatory abilities, balance skills became more robust.     

Effects of an early intervention group program for anxious and depressed adolescents: a pilot study

The Resourceful Adolescent Program is an early intervention program designed to enhance psychological resilience in adolescents with emotional problems. Eight adolescents with high anxious and/or depressive symptoms were treated with this 11-session group program. Treatment effects were examined by means of self-report questionnaires of anxiety, depression, and self-efficacy. Pre- and postintervention data showed reductions in anxiety and depression scores and a concomitant increase in adolescents' self-efficacy.     

Spiritual well-being and personality

The hypothesis that High and Low Spiritual Well-being groups have different personality profiles was tested with 319 psychology undergraduates (132 men and 187 women who completed the Revised NEO Personality Inventory and the Spiritual Well-being Scale for partial course credit. Univariate analyses of variance indicated that the High Spiritual Well-being group scored lower on Neuroticism and higher or Extraversion, Agreeableness. and Conscientiousness than the Low Spiritual Well-being group. Multivariate analysis of variance indicated that the two groups had significantly different personality profiles, supporting the hypothesis.     

Repetition effects for words and nonwords as indexed by event-related fMRI: a preliminary study

We have previously shown differential effects of stimulus familiarity on the repetition-related responses in right fusiform cortex to both faces and symbols. Repetition of familiar stimuli produced a response decrease, whereas repetition of unfamiliar stimuli produced a response increase. In the present experiment, we used words and nonwords as the familiar and unfamiliar stimuli respectively. In this case, the only fusiform region showing the familiarity-by-repetition interaction was in anterior left fusiform. This left-lateralisation of the fusiform interaction is consistent with our hypothesis that these repetition-related effects occur in the same regions responsible for perceptual recognition of familiar stimuli.