Self-selection biases in correlational studies based on questionnaires

It is commonly held that even where questionnaire response is poor, correlational studies are affected only by loss of degrees of freedom or precision. We show that this supposition is not true. If the decision to respond is correlated with a substantive variable of interest, then regression or analysis of variance methods based upon the questionnaire results may be adversely affected by self-selection bias. Moreover such bias may arise even where response is 100%. The problem in both cases arises where selection information is passed to the score indirectly via the disturbance or individual effects, rather than entirely via the observable explanatory variables. We suggest tests for the ensuing self-selection bias and possible ways of handling the ensuing problems of inference.The author would like to thank members of the Psychology Department at UWA for references on the illustrative example, namely the effects of sex-stereotyping on achievements in mathematics; thanks are also due to the anonymous reviewers whose comments resulted in material improvements to the paper.     

Comprehending homographs in aphasia

This study assessed 13 aphasic subjects' knowledge of the multiple meanings of homographs. The results indicated that the various meanings were less available to aphasic subjects than to normal subjects. In addition, specific meanings became less available as they became less typical although the number of meanings associated with a homograph did not influence performance. Aphasia type also did not influence performance. Performance on the experimental test was significantly correlated with auditory comprehension level and picture naming ability. The results were related to recent findings on semantic organization in aphasia.     

Intrinsic enjoyment and boredom coping scales: Validation with personality,evoked potential and attention measures

This paper reports the validation of brief, self-report measures of intrinsic enjoyment and boredom coping. Intrinsic enjoyment is characterized by intense involvement, interest and absorbed concentration; boredom coping is designed to reflect the disposition to restructure one's perceptions and participation in potentially boring activities so as to decrease boredom. Both traits are hypothesized to reflect the capacity for good attentional control across a variety of situations. Reliability was established by test-retest correlation and by an inter-item consistency measurement. Construct validity was established by comparison with previously-validated personality tests, real-life measures (such as Random Activities Experiential Sampling, which involves repeated self-report measures in daily life), as well as with laboratory measures of attention (including the averaged visual evoked potential (EP) and the Continuous Performance Test). Intrinsic enjoyment is significantly correlated with an independent measure of intrinsic involvement (low wish to be elsewhere in one's daily life), the affective experience of potency, self-reports of concentrating well with ease, high ego development, an internal locus of control, lack of boredom susceptibility and certain EP indices of attentional change and ‘cortical’ augmenting. Boredom coping is associated with a higher percent of time actually spent alone, high continuous performance task measures of attentional capacity, and low MMPI and Research Diagnostic Criteria indices of psychopathology.     

Trading relations in the perception of speech by 5-year-old children

Five-year-old children were tested for perceptual trading relations between a temporal cue (silence duration) and a spectral cue (F₁ onset frequency) for the “say-stay” distinction. Identification functions were obtained for two synthetic “say-stay” continua, each containing systematic variations in the amount of silence following the /s/ noise. In one continuum, the vocalic portion had a lower F₁ onset than in the other continuum. Children showed a smaller trading relation than has been found with adults. They did not differ from adults, however, in their perception of an “ay-day” continuum formed by varying F₁ onset frequency only. The results of a discrimination task in which the two acoustic cues were made to “cooperate” or “conflict” phonetically supported the notion of perceptual equivalence of the temporal and spectral cues along a single phonetic dimension. The results indicate that young children, like adults, perceptually integrate multiple cues to a speech contrast in a phonetically relevant manner, but that they may not give the same perceptual weights to the various cues as do adults.     

Forced classification: A simple application of a quantification method

This study formulates a property of a quantification method, the principle of equivalent partitioning (PEP). When the PEP is used together with Guttman's principle of internal consistency (PIC) in a simple way, the combination offers an interesting way of analyzing categorical data in terms of the variate(s) chosen by the investigator, a type of canonical analysis. The study discusses applications of the technique to multiple-choice, rank-order, and paired comparison data.This study was supported by the Natural Sciences and Engineering Research Council of Canada (Grant No. A7942). Comments on the earlier drafts from anonymous reviewers and the editor were much appreciated.     

Redundancy analysis for qualitative variables

Redundancy analysis (also called principal components analysis of instrumental variables) is a technique for two sets of variables, one set being dependent of the other. Its aim is maximization of the explained variance of the dependent variables by a linear combination of the explanatory variables. The technique is generalized to qualitative variables; it then gives implicitly a simultaneous optimal scaling of the dependent, qualitative variables. Examples are taken from the Dutch Life Situation Survey 1977, using Satisfaction with Life and Happiness as dependent variables. The analysis leads to one well-being scale, defined by the explanatory variables Marital status, Schooling, Income and Activity.The views expressed in this paper are those of the author and do not necessarily reflect the policies of the Netherlands Central Bureau of Statistics.     

The intergenerational transmission of relationship instability: A focus on emerging adult on-off relationships

This study extends prior research on the intergenerational transmission of relationship instability by examining parents' history of on-off relationships as a predictor of emerging adults' own cycling (i.e., breaking up and renewing with the same romantic partner). Data were collected at a large mid-western university from 702 emerging adults (18–25 years old). Multinomial logistic regression was used to predict the likelihood that participants had cycled in a past or current relationship. Results show that parental cycling increased the likelihood of offspring cycling in a past or current relationship relative to never cycling, and greater uncertainty about the future of the relationship was a mechanism through which such transmission occurred. Findings from this study demonstrate that parental relationship instability can even be consequential for the transient relationships within emerging adulthood, making family history a productive area to explore for practitioners working with cyclical partners and/or emerging adults.     

Increase in physiological inhibitory control results in better suppression of unwanted memories

Forgetting or suppressing a memory with unwanted content is just as important as remembering a desirable one. In addition to emphasizing the role of inhibitory control in memory suppression processes, neuropsychological studies have indicated that an intentional inhibition targeting a brain area may exert its inhibitory effects in seemingly unrelated areas through a common inhibitory network. In this study, we aimed to investigate whether the suppression of unwanted memories can be strengthened by recruiting an inhibitory task that can be simultaneously performed with a memory suppression task. Therefore, we manipulated the level of urinary urgency-induced inhibition of participants (N = 180) and test its effect on the suppression of unwanted memories using a Think/No-Think (T/NT) task. The results of our study indicated that individuals with high levels of urinary urgency demonstrated greater memory suppression compared to those with low urinary urgency. Findings and their implications are discussed within the context of cognitive and clinical perspectives, and recommendations are made for future research.