Estimating the polychoric correlation from misclassified data

Many variables that are used in social and behavioural science research are ordinal categorical or polytomous variables. When more than one polytomous variable is involved in an analysis, observations are classified in a contingency table, and a commonly used statistic for describing the association between two variables is the polychoric correlation. This paper investigates the estimation of the polychoric correlation when the data set consists of misclassified observations. Two approaches for estimating the polychoric correlation have been developed. One assumes that the probabilities in relation to misclassification are known, and the other uses a double sampling scheme to obtain information on misclassification. A parameter estimation procedure is developed, and statistical properties for the estimates are discussed. The practicability and applicability of the proposed approaches are illustrated by analysing data sets that are based on real and generated data. Excel programmes with visual basic for application (VBA) have been developed to compute the estimate of the polychoric correlation and its standard error. The use of the structural equation modelling programme Mx to find parameter estimates in the double sampling scheme is discussed.     

How does culture influence the degree of romantic loneliness and closeness?

A culture promoting a strong desire for romantic relationships can greatly influence feelings of romantic loneliness and of closeness. In this study, the authors hypothesized that when not in a romantic relationship, U.S. young adults experience greater degrees of romantic loneliness because of a high desire for romantic relationships, compared with Korean young adults. The authors also predicted that when in a romantic relationship, U.S. young adults experience greater closeness to their romantic partner than do Korean young adults. Results revealed that in a sample of 227 U.S. and Korean students, U.S. students reported significantly higher levels of romantic loneliness than did Koreans when not in a romantic relationship and significantly lower levels of romantic loneliness when in a stable romantic relationship. U.S. students also reported a greater degree of closeness in romantic relationships than did Korean students. The results suggest that Western cultures' strong emphasis on the importance of romantic relationships may unduly amplify individuals' levels of loneliness.     

Impaired color word processing at an unattended location: Evidence from a Stroop task combined with inhibition of return

A Stroop task with separate color bar and color word stimuli was combined with an inhibition-of-return procedure to examine whether visual attention modulates color word processing. In Experiment 1, the color bar was presented at the cued location and the color word at the uncued location, or vice versa, with a 100- or 1,050-msec stimulus onset asynchrony (SOA) between cue and Stroop stimuli. In Experiment 2, on Stroop trials, the color bar was presented at a central fixated location and the color word at a cued or uncued location above or below the color bar. In both experiments, with a 100-msec SOA, the Stroop effect was numerically larger when the color word was displayed at the cued location than when it was displayed at the uncued location, but with the 1,050-msec SOA, this relation between Stroop effect magnitude and location was reversed. These results provide evidence that processing of the color word in the Stroop task is modulated by the location to which visual attention is directed.     

The directionality and functional organization of frontoparietal connectivity during consciousness and anesthesia in humans

Frontoparietal connectivity has been suggested to be important in conscious processing and its interruption is thought to be one mechanism of general anesthesia. Data in animals demonstrate that feedforward processing of information may persist during the anesthetized state, while feedback processing is inhibited. We investigated the directionality and functional organization of frontoparietal connectivity in 10 human subjects anesthetized with propofol on two separate occasions. Multichannel electroencephalography and a computational method of assessing directed functional connectivity were employed. We demonstrate that directed feedback connectivity is diminished with loss of consciousness and returns with responsiveness to verbal command. We also applied the Dendrogram classification method to assess the global organization of directed functional connectivity during consciousness and anesthesia. We demonstrate a state-specific hierarchy and subject-specific subhierarchy in functional organization. These data support the hypothesis that specific states of human consciousness are defined by specific states of frontoparietal connectivity.     

The dynamics of daily events and well-being across cultures: when less is more

The authors examined cultural and individual differences in the relation between daily events and daily satisfaction. In a preliminary study, they established cross-cultural equivalence of 50 daily events. In the main study, participants in the United States, Korea, and Japan completed daily surveys on the 50 events and daily satisfaction for 21 days. The multilevel random coefficient model analyses showed that (a) the within-person association between positive events and daily satisfaction was significantly stronger among Asian American, Korean, and Japanese participants than among European American participants and (b) the within-person association between positive events and daily satisfaction was significantly weaker among individuals high in global life satisfaction than among those low in global life satisfaction. The findings demonstrate a weaker effect of positive events on daily well-being among individuals and cultures high in global well-being.     

Causation and Counterfactual Dependence

Recently Stephen Barker has raised stimulating objections to the thesis that, roughly speaking, if two events stand in a relation of counterfactual dependence, they stand in a causal relation. As Ned Hall says, however, this thesis constitutes the strongest part of the counterfactual analysis of causation. Therefore, if successful, Barker’s objections will undermine the cornerstone of the counterfactual analysis of causation, and hence give us compelling reasons to reject the counterfactual analysis of causation. I will argue, however, that they do not withstand scrutiny.     

Cue-exposure therapy to decrease alcohol craving in virtual environment.

During abstinence from alcohol, craving is elicited by the cues and contexts previously associated with alcohol, which contribute to relapse. To prevent the craving and relapse experienced by alcoholics, cue-exposure therapy (CET) has been used to extinguish the association between alcohol and alcohol-related cues and contexts. This study applied CET, using a virtual reality (VR) system, to eight members of an Alcoholics Anonymous group for eight sessions. Cues and contexts most likely to elicit an urge to drink were selected through a preliminary survey in order to compose VR-CET scenarios: a glass, a bottle, food, and a bar were judged to be the most tempting for people in alcohol dependence and abstinence. Using these cues and contexts, a Japanese-style pub and a western bar were created. Each session was administered for 30 minutes by a psychiatrist and included an introduction, immersion, VR navigation, interviews about feelings, and self-report questionnaires about cravings. The eight sessions consisted of initial and closing sessions and person-, object-, and situation-focused sessions. As a result, a reduction in cue-elicited craving after VR-CET was reported. A mean score of 15.75 (SD = 10.91) on the Alcohol Urge Questionnaire in the first session decreased to 11.50 (SD = 5.76) in the final session. This study suggests that using virtual reality can enhance the effectiveness of CET.     

Factors Associated with Functional Dependence in Alzheimer's Disease

The purpose of this study was to determine whether common geriatric conditions, family function, and nutritional problems have independent associations with functional dependence beyond the effect of cognitive impairment in patients with Alzheimer's disease. It was found that some common geriatric conditions affecting patients with Alzheimer's disease appear to have multiple and differential relationships with specific instrumental activities of daily living (IADLs) dependency. These results have implications for medical care. Preventing one condition may not be sufficient to prevent further IADL dependences because the conditions are independently related to individual outcome variables. Thus, multiple conditions may need to be managed concurrently if further functional dependence is to be expected.     

Analysis of Pelvis-Thorax Coordination Patterns of Professional and Amateur Golfers during Golf Swing

The aim of this research was to quantify the coordination pattern between thorax and pelvis during a golf swing. The coordination patterns were calculated using vector coding technique, which had been applied to quantify the coordination changes in coupling angle (γ) between two different segments. For this, fifteen professional and fifteen amateur golfers who had no significant history of musculoskeletal injuries. There was no significant difference in coordination patterns between the two groups for rotation motion during backswing (p = 0.333). On the other hand, during the downswing phase, there were significant differences between professional and amateur groups in all motions (flexion/extension: professional [γ] = 187.8°, amateur [γ] = 167.4°; side bending: professional [γ] = 288.4°, amateur [γ] = 245.7°; rotation: professional [γ] = 232.0°, amateur [γ] = 229.5°). These results are expected to be a discriminating measure to assess complex coordination of golfers' trunk movements and preliminary study for interesting comparison by golf skilled levels.