Gross primary productivity of a large metropolitan region in midsummer using high spatial resolution satellite imagery

Although gross primary productivity (GPP) is estimated with remote sensing over large regions of Earth, urban areas are usually excluded due to the lack of light use efficiency (LUE) parameters for urban vegetation and the spatial heterogeneity of urban land cover. Here, we estimated midsummer GPP, both within and among vegetation and land-use types, across the Minneapolis-Saint Paul, Minnesota metropolitan region. We derived LUE parameters for urban vegetation types using estimates of GPP from tree sap flow and eddy covariance CO₂ flux observations, and from fraction of absorbed photosynthetically active radiation based on 2 m resolution WorldView-2 satellite imagery. Mean GPP per unit land area (including vegetation, impervious surfaces, and soil) was 2.64 g C m^?2 d^?1, and was 4.45 g C m^?2 d^?1 per unit vegetated area. Mapped GPP estimates were within 11.4% of estimates from independent tall tower eddy covariance measurements. Turf grass GPP had a larger coefficient of variation (0.18) than other vegetation classes (~0.10). Vegetation composition was largely consistent across the study area. Excluding golf courses, mean land-use GPP for the total study area varied more by percent vegetation cover (R²?=?0.98, p?<?0.001) than by variability within vegetation classes (R²?=?0.21, p?=?0.19). Urban GPP in general was less than half that of natural forests and grasslands in the same climate zone.     

Work–home conflict and facilitation across four different family structures in Norway

The purpose of this study was to examine how work–home conflict and facilitation vary among people living in different family structures in Norway, here conceptualized as: two-parent families; single parents; childless couples; and singles. The study used data from a Norwegian study on occupational health (N=2414). We hypothesized that respondents living in two-parent families experience more work–home conflict and facilitation than others due to more complex role expectations. Similarly, we hypothesized that the effect of workload and autonomy on work–home conflict and facilitation would be stronger among this group. The results indicate that conflict between work and home life are more profound among those living in two-parent families and among single parents than among childless couples and singles. Work-to-home facilitation did not vary by family structure, whereas the childless couples reported more home-to-work facilitation. Furthermore, with a few exceptions the effects of workload and autonomy on work–home conflict and facilitation did not differ by family structure.     

Elterliche Arbeitslosigkeitsdynamiken und Bildungsverläufe vom Ende der Grundschulzeit bis zum jungen Erwachsenenalter

In the present study, we examine the influence of parental unemployment on the educational outcomes of children in Germany. We consider the educational pathways from the transition to secondary school until early adulthood at age 23. In particular, we focus on the question whether children of unemployed parents are less likely to enroll in tertiary education. In addition, we look at enrolment into educational tracks at the beginning and the end of secondary school. We use data from the Socio-Economic Panel (SOEP). We address the problem of social selectivity into unemployment by means of a comprehensive control variable approach within the framework of random effects-models. In addition, we estimate fixed effects-models using siblings’ information. As a result, it is evident that a significant influence of unemployment on educational outcomes can be observed both with comprehensive control of status characteristics as well as in sibling models. However, this does not apply to all educational outcomes and not to all forms of unemployment.     

John Money,Ph.D

It was hypothesized that knowledge of venereal disease is correlated with attitudes toward seeking treatment and willingness to prevent the spread of infection. A questionnaire containing knowledge, attitude, and demographic items was distributed to a random sample of 700 college students in four New York City colleges. Results from the 547 completed questionnaires suggested that the majority of the students lacked adequate knowledge of venereal disease. Significant but low positive correlations between knowledge and attitude were obtained for some sub‐groups of the sample. A consistent negative relationship between perceived knowledge and actual knowledge was found. Implications related to sexual behavior and venereal disease education are discussed.     

On spatiotemporal prediction for on-line monitoring data

Spatiotemporal prediction is of interest in many areas of applied statistics, especially in environmental monitoring with on-line data information. At first, this article reviews the approaches for spatiotemporal modeling in the context of stochastic processes and then introduces the new class of spatiotemporal dynamic linear models. Further, the methods for linear spatial data analysis, universal kriging and trend surface prediction, are related to the method of spatial linear Bayesian analysis. The Kalman filter is the preferred method for temporal linear Bayesian inferences. By combining the Kalman filter recursions with the trend surface predictor and universal kriging predictor, the prior and posterior spatiotemporal predictors for the observational process are derived, which form the main result of this article. The problem of spatiotemporal linear prediction in the case of unknown first and second order moments is treated as well.     

Role expectations and definitions: a comparison of female transsexuals and lesbians

A new study on female transsexuals and lesbians is reported. A matched-group comparison of 15 women in each sample suggests that the two groups do not differ in overall intelligence, although lesbians, unlike female transsexuals, tended to have a significantly higher verbal IQ than performance IQ. Both groups showed a similar response pattern on the Embedded Figures Test but differed on the Draw-A-Person Test, The Guilford-Zimmerman Temperament Survey, and the Bem Androgyny Scale. Whereas the female transsexual group reflected a more rigid gender role stereotype, the lesbians saw their options as more androgynous.     

Bayes estimates in multivariate semiparametric linear models

Bayes estimates are derived in multivariate linear models with unknown distribution. The prior distribution is defined using a Dirichlet prior for the unknown error distribution and a normal-Wishart distribution for the parameters. The posterior distribution is determined and explicit expressions are given in the special cases of location-scale and two-sample models. The calculation of self-informative limits of Bayes estimates yields standard estimates.     

Multilevel and nonlinear panel data models

Summary This paper presents a selective survey on panel data methods. The focus is on new developments. In particular, linear multilevel models, specific nonlinear, nonparametric and semiparametric models are at the center of the survey. In contrast to linear models there do not exist unified methods for nonlinear approaches. In this case conditional maximum likelihood methods dominate for fixed effects models. Under random effects assumptions it is sometimes possible to employ conventional maximum likelihood methods using Gaussian quadrature to reduce a T-dimensional integral. Alternatives are generalized methods of moments and simulated estimators. If the nonlinear function is not exactly known, nonparametric or semiparametric methods should be preferred. Helpful comments and suggestions from an unknown referee are gratefully acknowledged.