Spline smoothing with model-based penalties

Nonparametric regression techniques, which estimate functions directly from noisy data rather than relying on specific parametric models, now play a central role in statistical analysis. We can improve the efficiency and other aspects of a nonparametric curve estimate by using prior knowledge about general features of the curve in the smoothing process. Spline smoothing is extended in this paper to express this prior knowledge in the form of a linear differential operator that annihilates a specified parametric model for the data. Roughness in the fitted function is defined in terms of the integrated square of this operator applied to the fitted function. A fastO(n) algorithm is outlined for this smart smoothing process. Illustrations are provided of where this technique proves useful.     

Internalizing and externalizing characteristics of sexually and/or physically abused children

This study evaluates the behavioral consequences of childhood abuse (sexual, physical, or both), with particular focus on prevalence of posttraumatic stress disorder (PTSD). Three abuse type groups and nonabused controls were contrasted on behavioral rating scales and on structured psychiatric interview data. The participants (109 abused children and 16 normal control children) were recruited from Arkansas Children’s Hospital and local agencies for abused children. As expected, proportionately more females than males were sexually abused. Overall, males were rated as more disturbed than females. Type of abuse did not consistently influence behavioral ratings. Externalizing scores were significantly higher than internalizing scores in all abused groups. PTSD was diagnosed in 50% of the abused children, with a higher rate for boys who had been sexually abused as opposed to physically abused only (58% versus 13%). The most frequent comorbid condition with PTSD was Separation Anxiety. Sexually abused boys were hospitalized for psychiatric treatment at a higher rate than were other abused children.     

The organization of multidimensional selection on the basis of color and shape: An event-related brain potential study

In this paper, we examine whether color and shape, tied to a single object in space, (1) are identified and selected in series or in parallel, (2) are identified and selected in a dependent, self-terminating manner or in an independent and exhaustive manner, and (3) are conjoined by a feature integration process before or only after an initial stage of separate attribute analyses has finished. We measured response time and the selection negativity (SN) derived from event-related brain potentials when participants responded to a unique conjunction of color and shape in a go/no-go target detection task. The discriminability of the color and the shape of the conjunction was manipulated in three conditions. When color and shape were easy to discriminate, the SNs to color and shape started at the same time. When one attribute was less discriminable, the SN to that attribute started later, but not the SN to the complementary attribute. This suggests that color and shape are identified and selected in parallel. In all three discriminability conditions, the SNs to color and shape were initially independent but later interacted. This suggests that color and shape are initially selected independently and exhaustively, after which their conjunction is analyzed. The SN to local shape features started later than that to the conjunction of color and global shape features, which suggests that feature integration can start before the analyses of the separate attributes have finished.     

Perceived Overqualification, Emotional Support, and Health

In the present study, we examined the effects of perceived overqualification on health and the moderating effect of emotional support. Exploratory and confirmatory factor analyses found 2 indicators of perceived overqualification: "mismatch" and "no-grow." Perceived mismatch had a significant negative effect on health but perceived no-grow did not. The main effect revealed that the greater the perceived emotional support, the greater the health. The significant interaction of perceived emotional support and mismatch, and perceived emotional support and no-grow on health indicates that the negative effects of overqualification on health was greater for those perceiving low emotional support than for those perceiving high emotional support. The significance of social support in illuminating the relationship between perceived overqualification and health are discussed.     

Apocalyptic Argument and the Anticipation of Catastrophe: the Prediction of Risk and the Risks of Prediction

This essay proposes to extend the model of apocalyptic argument developedin my recent book Arguing the Apocalypse (OLeary, 1994) beyond the study ofreligious discourse, by applying this model to the debate over awell-publicized earthquake prediction that caused a widespread panic in theAmerican midwest in December, 1990. The first section of the essay willsummarize the essential elements of apocalyptic argument as I have earlierdefined them; the second section will apply the model to the case of the NewMadrid, Missouri, earthquake prediction, in order to demonstrate thatcertain patterns of reasoning characteristic of religious apocalyptic arepresent in the discourse over an anticipated local disaster. My ultimatepurpose is to show that predictions of global and local catastrophe mayserve as extreme cases that will illuminate the dynamics of predictiveargument in general. Thus my argument will seek to undercut Daniel Bellsdistinction between prophecy and prediction (Bell, 1973) by establishingthat these discourses share identifiable formal and substantivecharacteristics, and depend for their rhetorical effect on anxiety, hope,far, and excitement as modes of temporal anticipation.     

LONGITUDINAL STUDY OF PROCRASTINATION, PERFORMANCE, STRESS, AND HEALTH:

Abstract— Procrastination is variously described as harmful, innocuous, or even benefical. Two longitudinal studies examined procrastination among students. Procrastinators reported lower stress and less illness than nonprocrastinators early in the semester, but they reported higher stress and more illness late in the term, and overall they were sicker. Procrastination thus appears to be a self-defeating behavior pattern marked by short-term benefits and long-term costs.     

Imperialism,nationalism and missionaries: Lessons from Sudan for the twenty‐first century

Muslim‐Christian relations in modem Sudanese history involve the tensions created by the transition from imperial rule to independence and by the impact of contemporary processes of globalization. The conflicts between Christian missionaries and the newly‐independent government of Sudan in the early 1960s reflected the tensions between old mission‐station style Christian activities and attempts by a military régime to impose measures of ‘national’ unification. Opportunities for creating institutions for constructive interactions were missed or not even conceived. Lessons from the experiences of the early 1960s emphasize the importance of viewing Muslim‐Christian relations in the 1990s in the context of the actual current conditions rather than imposing out‐of‐date images on existing realities.     

Effect of Persuasive Appeals in AIDS PSAs and Condom Commercials on Intentions to Use Condoms1

The study compared the effect of five persuasive appeals used in AIDS PSAs and condom commercials (fear arousal-no sex/condom theme; fear arousal-sex/condom theme; erotic; humorous; factual) on 122 male and 114 female college students' i]ntentions to use and taking of condoms. Results showed that the two fear appeals were more effective than other appeals in increasing intentions to use condoms with a new partner. The fear appeal–no sex/condom theme was more effective than other appeals for increasing intentions to use condoms with a steady partner. Compared to men, women rated commercials as more effective for increasing intentions to use condoms with a new partner. Persuasive appeals had no effect on the taking of free condoms. The best predictor of commercial effectiveness was the degree to which a commercial evoked a high fear of AIDS. Other significant predictors were subjects' a]ttitude toward condom use and commercial qualities of being humorous, romantic, credible, and factual. Implications are that all five types of appeals are potentially effective for use in AIDS PSAs. Recommendations include combining appeals (e.g. fear with erotic) and emphasizing the positive features of condom use.     

The value of possessions in compulsive hoarding: Patterns of use and attachment

Hoarding behavior, patterns of use of possessions, and emotional attachment to possessions were examined among a sample of female undergraduates and a sample of community volunteers. Hoarding behavior was associated with a decreased frequency of use of possessions and excessive concern about maintaining control over possessions. Furthermore, high scores on the hoarding scale were associated with higher levels of perceived responsibility for: (1) being prepared; and (2) the well-being of the possession. Hoarding was also associated with greater emotional attachment to possessions and to the reliance on possessions for emotional comfort. The implications of these findings for the definition of hoarding are discussed.