OUTLIER DETECTION AND TREATMENT IN I/O PSYCHOLOGY: A SURVEY OF RESEARCHER BELIEFS AND AN EMPIRICAL ILLUSTRATION

Extreme data points, or outliers, can have a disproportionate influence on the conclusions drawn from a set of bivariate correlational data. This paper addresses two aspects of outlier detection. The results of a survey regarding how published researchers prefer to deal with outliers are presented, and a set of 183 test validity studies is examined to document the effects of different approaches to the detection and exclusion of outliers on effect size measures. The study indicates that: (a) there is disagreement among researchers as to the appropriateness of deleting data points from a study; (b) researchers report greater use of visual examination of data than of numeric diagnostic techniques for detecting outliers; and (c) while outlier removal influenced effect size measures in individual studies, outlying data points were not found to be a substantial source of variance in a large test validity data set.     

Understanding of relational time terms before and after in Parkinsonian patients

The role of the relational time terms before and after in language comprehension was investigated using patients with Parkinson's disease (PD) and normal controls (NC) in Greek. Results lead to the following four conclusions: (a) Comprehension by PD patients of before and after constructions displaying syntactic, semantic, and cognitive constraints equivalent to those of English is significantly different from that of NC matched on chronological age, sex, education, and socioeconomic status. (b) Before is better understood than after. (c) Syntactic variables, when semantic effects are partialed out, do not affect performance. The same is true of semantic effects when syntactic variables are partialed out. (d) Order of mention of events is a predominant source of errors when syntax and semantics are controlled. The data are discussed in relation both to findings with aphasics and to developmental results on the same time terms.     

We've come a long way,maybe: College students' plans for work and family

Young men and women today face considerable choices as they plan for family and work. We explore college students' educational preparations, as well as their attitudes, orientations, and expectations for work and family. Although we find some changes toward a more gender-equal society, we also find potential conflicts which these individuals will have to face as they attempt to combine work and family roles. Women and men are doing equally well in college, both men and women have equal commitments to work roles, and both value family. However, both men and women expect that women will play a more prominent role in the family and men a stronger role in the workplace. The orientation and plans of these college students do not anticipate symmetrical relationships in which both men and women share household and work responsibilities.We are grateful to Brenda K. Hawks, Sue Curry Jansen, and Judith Lasker for their careful readings of earlier drafts of this paper. Special thanks go to the students in SR377/477 for their major contribution in collecting the data which are analyzed herein.     

The assessment of suicidal behavior in adolescents.

All available assessment instruments (N = 29) used to study suicidal behaviors in adolescents and young adults (age 12-20) were collected and reviewed. Instruments were found to vary substantially in purpose, format, informat, and theoretical orientation. The items from these tools (N = 461) were categorized according to behavior type (thoughts, feelings, or actions) and content categories (death/life-related, disease-promoting/preventing, injury-producing/reducing, person-reducing/enhancing, and factual information). The majority of the items were found to assess thoughts and were focused on death-related content. Recommendations include the need for more rigorous validation of instruments, clearer operational definitions, additional normative information, and expansion of the pool of available items to encompass a broader array of self-destructive behaviors.     

Reflections on the process of psychotherapeutic change as applied to medical situations

This article takes the basic ideas on the process of changing implicit knowledge put forward in this special issue, and extends them beyond psychotherapy to include other therapeutic relationships that occur in medicine. One vignette, from an encounter between a medical student and a dying patient, illustrates how a “moment of meeting” changes the student as well as the patient. The second shows how therapeutic interventions for new mothers with their newborn infants involve “moments of meeting” that alter the mother's implicit knowledge of her baby and of herself as a mother. © 1998 Michigan Association for Infant Mental Health     

Illusory trust: Kanizsa shapes incidentally increase trust and willingness to invest

Previous research has shown that the completion of basic perceptual processes is intrinsically pleasant. In the absence of diagnostic and objective cues to trustworthiness, nondiagnostic factors such as positive affect can incidentally lead to reported and behavioral trust. On the basis of these two premises, it was tested whether positive affect from the completion of perceptual processes has implications for the formation of trust in first-time business-consumer interactions. We tested this hypothesis in four experiments, using the famous Kanizsa illusion as an exemplary perceptual process that has been shown to trigger positive affect. We found that participants trusted companies who featured a Kanizsa shape as their logo more than companies with closely matched logos that did not allow for the completion of a basic perceptual process. This was evident on self-reported (Experiment 1) as well as behavioral (Experiments 2–4) measures of trust. This effect even persisted under incentivized conditions (Experiment 4) and was partially mediated by the intrinsic pleasantness of perception (Experiment 3). These findings for the first time demonstrate that positive affect is not the only consequence of perception, but rather has further trickle-down consequences for social judgments and economic decision making. Perceptual illusions seem to elicit illusory trust. Therefore, these novel findings bear important implications not only for both logo design and marketing but also for consumer decision making.     

Opium of the people? National identification predicts well-being over time

Social group membership and its social-relational corollaries, for example, social contact, trust, and support, are prophylactic for health. Research has tended to focus on how direct social interactions between members of small-scale groups (i.e., a local sports team or community group) are conducive to positive health outcomes. The current study provides evidence from a longitudinal cross-cultural sample (N = 6,748; 18 countries/societies) that the prophylactic effect of group membership is not isolated to small-scale groups, and that members of groups do not have to directly interact, or in fact know of each other to benefit from membership. Our longitudinal analyses suggest that national identification (strength of association with the country/society of which one is a citizen) predicts lower anxiety and improved health; national identification was in fact almost as positively predictive of health status as anxiety was negatively predictive. The findings indicate that identification with large-scale groups, like small-scale groups, is palliative, and are discussed in terms of globalization and banal nationalism.     

Solving the puzzle of deliberate self-harm: the experiential avoidance model

Despite increasing attention to the phenomenon of deliberate self-harm (DSH), the literature currently lacks a unifying, evidence-based, theoretical framework within which to understand the factors that control this behavior. The purpose of the present paper is to outline such a framework-the Experiential Avoidance Model (EAM) of DSH. The EAM poses that DSH is primarily maintained by negative reinforcement in the form of escape from, or avoidance of, unwanted emotional experiences. Literature on factors that may lead to experiential avoidance is reviewed, along with the mounting empirical evidence that DSH functions to help the individual escape from unwanted emotional experiences. The EAM integrates a variety of research on emotions, experiential avoidance, and DSH within a clinically useful framework that sparks novel research directions.     

Forging difference out of similarity: the multiplicity of corrective experience

In the context of work with an adult survivor of childhood sexual abuse, the interplay of multiple forms of engagement contributing to therapeutic action is explored. The compulsion to repeat old patterns is seen to be gradually overcome by new corrective experience in which the whole of the patient's sense of the analyst as a person is greater than the sum of its parts. Interpretation of enactments--often involving patterns of dominance and submission--is complemented by a range of "helpful" actions that must be detoxified. That process entails the progressive differentiation of coercion and influence, on the one hand, and of compliance and responsiveness, on the other In the end, autonomy and creative responsiveness emerge as integral to each other rather than as mutually exclusive. This development requires that the patient gradually relinquish an "essentialist" view of self and other in favor of a "constructivist" view, in which the ambiguity of experience offers opportunities for new forms of relational engagement and understanding.