Ecological and Motivational Determinants of Activation: Studying Compared to Sports and Watching TV

How can we enhance activation? Studying shouldbe a challenging, yet rewarding activity forstudents who intend to graduate. The Flowtheory (Csikszentmihalyi, 1990, 1997) predictsthat differential levels of perceived challengeand skill (flow) are related to optimizedmental states and increased activation.However, the influence of concurrent mentalstates and specific environmental cues for thisstate of optimal experience is unknown. In thisstudy we explore the contextual and subjectivedeterminants of flow in relation to activationin studying, and compare this with sports andwatching TV or listening to the radio. Method: 43 undergraduate students at theUniversity of Maastricht were assessed with theExperience Sampling Method for one week(Delespaul, 1995). At random moments 10 timeseach day subjects evaluated the social context,activities, and mood states. Analyses were donewith multilevel random regression techniques.Results: We replicated the predictedflow-related patterns in activation andemotions. While overall activation wasincreased in high challenging moments(β = 0.51; 95% CI: 0.36, 0.19), thiseffect was less pronounced during study(β = ?0.16; 95% CI: ?0.25, ?0.07). Skillslevels did not affect activation(β = ?0.01; 95% CI: ?0.06, 0.05).Concurrent emotions were independently andadditionally related to activation(Δχ² ₍₄₎ = 117.12,p < 0.0001). Unexpectedly, activation increasedwith demotivation (β = ?0.12; 95% CI:0.16, 0.07). We found highly significant andadditional effects of context for all theactivities (study: χ² = 732.63;p < 0.0001; R² = 0.30; active leisure:χ² = 753.40; p < 0.0001; R² = 0.31;and passive leisure: χ² = 555.86;p < 0.0001; R² = 0.24). Conclusions. TheFlow theory is a valuable model leading topredictions of optimal experience as well asactivation. However, the dynamics of activityengagement are more complex and related toconcurrent emotions and context. In the Dutchstudent culture, escaping boredom or compulsoryduties seems to drive individuals more thanpursuing flow.     

Sexual orientation as destiny

The article argues that social constructionists are referring to labels applied to sexual orientation while essentialists are discussing sexual orientation itself. Although a review of the literature shows that various labels are applied to sexual orientation, these labels do not markedly affect its reality. Sexual orientation, defined as erotic attraction rather than sexual behavior, is established at an early age and largely immutable in adulthood.     

Multivariate extreme-value distributions with applications to environmental data

Some parametric families of multivariate extreme-value distributions have been proposed in recent years; several additional parametric families are derived here. The parametric models are fitted, using numerical maximum likelihood, to some environmental multivariate extreme data sets consisting of extreme concentrations of a pollutant at several monitoring stations in a region. Some multivariate nonnormal data analysis techniques are proposed to aid in the likelihood analysis. The new models, together with previous models, appear to be adequate for inferences in that they cover a wide range of possible dependence patterns.     

Numerical optimization and surface estimation with imprecise function evaluations

This paper presents an investigation of a method for minimizing functions of several parameters where the function need not be computed precisely. Motivated by problems requiring the optimization of negative log-likelihoods, we also want to estimate the (inverse) Hessian at the point of minimum. The imprecision of the function values impedes the application of conventional optimization methods, and the goal of Hessian estimation adds a lot to the difficulty of developing an algorithm. The present class of methods is based on statistical approximation of the functional surface by a quadratic model, so is similar in motivation to many conventional techniques. The present work attempts to classify both problems and algorithmic tools in an effort to prescribe suitable techniques in a variety of situations. The codes are available from the authors' web site http://macnash.admin.uottawa.ca/~rsmin/.