On the importance of avoiding shortcuts in applying cognitive models to hierarchical data

Psychological experiments often yield data that are hierarchically structured. A number of popular shortcut strategies in cognitive modeling do not properly accommodate this structure and can result in biased conclusions. To gauge the severity of these biases, we conducted a simulation study for a two-group experiment. We first considered a modeling strategy that ignores the hierarchical data structure. In line with theoretical results, our simulations showed that Bayesian and frequentist methods that rely on this strategy are biased towards the null hypothesis. Secondly, we considered a modeling strategy that takes a two-step approach by first obtaining participant-level estimates from a hierarchical cognitive model and subsequently using these estimates in a follow-up statistical test. Methods that rely on this strategy are biased towards the alternative hypothesis. Only hierarchical models of the multilevel data lead to correct conclusions. Our results are particularly relevant for the use of hierarchical Bayesian parameter estimates in cognitive modeling.     

The cyber dating violence inventory. Validation of a new scale for online perpetration and victimization among dating partners

Cyber dating abuse is a new kind of dating violence. Several recent measures assess this phenomenon, but do not focus on a severe aggression that aims to spoil a partner’s relational network (relational cyber abuse). This study developed and validated the Cyber Dating Violence Inventory (CDVI) with 1405 adolescents and young adults (M_age = 18.17; SD_age = 2.39; 65.1% females), an instrument that considers the relational dimension of online dating abuse. Exploratory and confirmatory factor analyses found two correlated factors (Psychological and Relational) for both perpetration and victimization, showing good reliability. CDVI factors were positively correlated with offline dating violence, showing good criterion validity. This instrument has clinical and educational implications.     

The use of reaction time measures to evaluate nonword reading in primary progressive aphasia

We reported on a subject with nonfluent primary progressive aphasia (PPA), NL, who demonstrated an impaired ability to make rhyme judgments (Dowhaniuk, Dixon, Roy, Black, & Square, in press). Our hypothesis was that these deficits represent a precursor to phonological alexia. However, no definitive evidence supported the existence of a phonological reading impairment as NL made relatively few errors reading nonwords. To further evaluate NL's nonword reading, nonword and real word reaction times were compared. NL's reaction times were significantly longer for only nonwords compared to the slowest control subject. We then assessed the first two stages of processing involved in nonword reading (Coltheart, 1996). NL did not demonstrate deficits with graphemic parsing or phoneme assignment. His continuing problems with auditory rhyme judgments support the presence of a phonological processing deficit not specific to reading. We conclude that reaction time measures allow for the detection of subtle nonword reading deficits.     

The School and Community Study: Characteristics of Students Who Have Emotional and Behavioral Disabilities Served in Restructuring Public Schools

We present selected initial results from a study investigating the effects of school restructuring and reform activities on outcomes for students who are identified as having serious emotional and behavioral disabilities. A review of the literature revealed six key areas of reform for investigation: accountability, governance, parent involvement, includedness, curriculum and instruction, and pro-social discipline. Ten schools (five elementary, two K-8, one middle, and two high schools) actively engaged in school restructuring and reform efforts were selected to participate in the study, and their status related to these six areas is presented. Characteristics of the students identified as having emotional and behavioral disabilities and served in these schools in special education settings (N = 116) are described. Results from the administration of standardized assessments revealed that these students have significant levels of emotional and behavioral disabilities that impair their functioning at school and at home. Further, school staff are providing the majority of counseling services to these students during the school day, with non-school professionals providing services to 25% of the students.     

Gestural imitation and limb apraxia in corticobasal degeneration

Limb apraxia is a common symptom of corticobasal degeneration (CBD). While previous research has shown that individuals with CBD have difficulty imitating transitive (tool-use actions) and intransitive non-representational gestures (nonsense actions), intransitive representational gestures (actions without a tool) have not been examined. In the current study, eight individuals with CBD and eight age-matched healthy adults performed transitive, intransitive representational and intransitive non-representational gestures to imitation. The results indicated that compared to controls, individuals with CBD were significantly less accurate in the imitation of transitive and intransitive non-representational gestures but showed no deficits for the imitation of intransitive representational gestures. This advantage for intransitive representational gestures was thought to be due to fewer demands being placed on the analysis of visual-gestural information or the translation of this information into movement when imitating these gestures. These findings speak to the importance of context and the representation of gestures in memory in gesture performance.     

Pantomime and imitation of limb gestures in relation to the severity of Alzheimer's disease

The present study was designed to investigate the relationship between performance of limb gestures and the severity of Alzheimer's disease (A.D.). Apraxia tends to occur at later stages of A.D., and the severity of apraxia has been shown to vary with the severity of A.D. dementia. Participants were 19 mild (including 9 with no cognitive impairment and 10 with mild impairment) and 18 moderate A.D. patients as well as 25 controls and they were asked to pantomime (P) or imitate (both concurrent (CI) and delayed (DI)), eight transitive gestures to assess praxis performance. Results indicated that the moderate patients performed less accurately than mild and non-impaired patients, and that across all groups, the imitation conditions were performed less accurately than pantomime, relative to controls. Correlational analyses revealed that MMSE scores were correlated with all three performance conditions suggesting that impaired praxis performance may relate to more global impairment. Finally, a frequency analysis was conducted to examine whether A.D. patients showed patterns of apraxia as described in Roy's model (1996). Results indicated that A.D. patients showed greatest impairment on pattern 7 (deficits in P, DI, and CI), reflecting late-stage gesture production, with a greater frequency of moderate patients exhibiting each apraxic pattern.     

MMPI-2 validity scale characteristics in a correctional sample

The current study investigated the proportion of content-nonresponsive and content-responsive faking Minnesota Multiphasic Personality Inventory-2 (MMPI-2) protocols in a state corrections sample. Participants were 51,486 inmates who completed the MMPI-2 at the time they entered the Ohio Department of Rehabilitation and Correction system. Overall, approximately 79% of the study participants produced valid profiles. Of the entire study sample, 11.3% produced content-nonresponsive profiles, and 9.4% produced content-responsive faking profiles. African Americans produced a higher proportion of content-nonresponsive profiles than Caucasians, and women were slightly more likely than men to produce content-responsive faking profiles. Differences in level of education between African Americans and Caucasians did not account for the disparity in content-nonresponsive profiles. Implications for current practice and future research are discussed.     

Reactions to gay men: Contact and overcorrection in an employee selection simulation

The current study examines the role of contact on reactions to gay and heterosexual targets by U.S. heterosexual college students. Aversive bias research finds that minority group members receive unfavorable evaluations only when non-category-based information justifies bias. We argue that under other conditions, namely absence of conditions justifying bias, minority group members receive more favorable evaluations than non-minorities, an effect we term overcorrection. We apply this research to the study of attitudes toward gay men. The current study examines this effect on evaluations of a highly qualified male job candidate who is either gay or heterosexual and flawed or not flawed. We predicted and found, among 180 college students, that the overcorrection effect was present only for those individuals who have experienced no friendships with gay men. Those individuals who do have gay male friends did not exhibit overcorrection. We interpret this result as an indication that individuals who have gay friends (contact) ignore category information such as gay/ heterosexual and are more likely to exhibit truly egalitarian ratings. Implications for aversive bias and outgroup covariation perspectives are discussed. We presented portions of this paper at the 2000 Western Psychological Association conference, Maui, HI.     

Universal sex differences in the desire for sexual variety: tests from 52 nations, 6 continents,and 13 islands

Evolutionary psychologists have hypothesized that men and women possess both long-term and short-term mating strategies, with men's short-term strategy differentially rooted in the desire for sexual variety. In this article, findings from a cross-cultural survey of 16,288 people across 10 major world regions (including North America, South America, Western Europe, Eastern Europe, Southern Europe, Middle East, Africa, Oceania, South/Southeast Asia, and East Asia) demonstrate that sex differences in the desire for sexual variety are culturally universal throughout these world regions. Sex differences were evident regardless of whether mean, median, distributional, or categorical indexes of sexual differentiation were evaluated. Sex differences were evident regardless of the measures used to evaluate them. Among contemporary theories of human mating, pluralistic approaches that hypothesize sex differences in the evolved design of short-term mating provide the most compelling account of these robust empirical findings.