The Distribution of Earnings Profiles in Longitudinal Data

We take advantage of our longitudinal data to explore individual variation in the parameters of individual earnings functions. (1) For this purpose we fit an earnings function to each of the individual histories in the sample.(2) We then try to ascertain the extent to which the estimated variation in individual parameters helps in explaining the cross-sectional variation in earnings.(3) we further inquire into the relation between the individual parameters and a vector of personal characteristics, as well as(4) into indirect (via variables and parameters) and direct effects of these characteristics on earnings.

The measurement and determinants of skill acquisition in young workers' first job

The article analyses participation in five types of training (formal on-site, formal off-site, informal co-worker training, learning by watching and learning by doing) and self-assessed skill acquisition in young Flemish workers' first job. A skill production function is estimated whereby the simultaneity of participation in the different types of training and skill acquisition is taken into account. The results clearly demonstrate the importance of informal training. Formal training participation is found to be only a fraction of total training participation. Moreover, the determinants of total training participation and skill acquisition differ from those of formal training participation. While some training types are complementary, others are clearly substitutes. Finally, most types of training generate additional skills. Nonetheless, learning by doing is found to be complementary to formal education in the production of both specific and general skills, whereas formal training serves as a substitute

Methanol production by a broad phylogenetic array of marine phytoplankton

© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PLoS 11 (2016): e0150820, doi:10.1371/journal.pone.0150820.Methanol is a major volatile organic compound on Earth and serves as an important carbon and energy substrate for abundant methylotrophic microbes. Previous geochemical surveys coupled with predictive models suggest that the marine contributions are exceedingly large, rivaling terrestrial sources. Although well studied in terrestrial ecosystems, methanol sources are poorly understood in the marine environment and warrant further investigation. To this end, we adapted a Purge and Trap Gas Chromatography/Mass Spectrometry (P&T-GC/MS) method which allowed reliable measurements of methanol in seawater and marine phytoplankton cultures with a method detection limit of 120 nanomolar. All phytoplankton tested (cyanobacteria: Synechococcus spp. 8102 and 8103, Trichodesmium erythraeum, and Prochlorococcus marinus), and Eukarya (heterokont diatom: Phaeodactylum tricornutum, coccolithophore: Emiliania huxleyi, cryptophyte: Rhodomonas salina, and non-diatom heterokont: Nannochloropsis oculata) produced methanol, ranging from 0.8–13.7 micromolar in culture and methanol per total cellular carbon were measured in the ranges of 0.09–0.3%. Phytoplankton culture time-course measurements displayed a punctuated production pattern with maxima near early stationary phase. Stabile isotope labeled bicarbonate incorporation experiments confirmed that methanol was produced from phytoplankton biomass. Overall, our findings suggest that phytoplankton are a major source of methanol in the upper water column of the world’s oceans.This project was solely supported by a grant to TJM from the National Science Foundation (Award# CHE-OCE 1131415)

Measurement of the Branching Fractions for D^0 → π^-e^+v_e and D^0 → + K^-e^+V_e and Determination of │V_(cd)/V_(cs)│^2

Measurements of the exclusive branching fractions B(D^0→π^-e^+ν_e) and B(D^0→K^-e^+ν_e), using data collected at the ψ(3770) with the Mark III detector at the SLAC e^+e^- storage ring SPEAR, are used to determine the ratio of the Kobayashi-Maskawa matrix elements │V_(cd)/V_(cs)│^2 =0.057_(-0.015)^(+0.038)±0.005

Search for the decay D^0→K^0e^+e^-

A search for the decay of the charmed meson D^0→K^0e^+e^- is presented, based on data collected at the ψ(3770) resonance with the Mark III detector at the SLAC storage ring SPEAR. No evidence for this process is found, resulting in an upper limit on the decay branching ratio of 1.7×10^(-3) at the 90% confidence level

Composition of primary cosmic rays near the bend from a study of hadrons in air showers at sea level

Data on hadrons in air showers arriving at sea level were studied to find sensitivity to primary cosmic ray composition. The rate of showers which satisfy minimum shower density and hadron energy requirements as well as the rate of showers containing hadrons delayed with respect to the electron shower front are compared to Monte Carlo simulations. The data on the rate of total triggers and delayed hadrons are compared to predicted rates for two models of primary composition. The data are consistent with models which require an increasing heavy nuclei fraction near 10 to the 15th power eV. The spectra which are consistent with the observed rate are also compared to the observed shower size spectrum at sea level and mountain level

A matter of culture and cost? A comparison of the employment decisions made by mothers with a lower, intermediate and higher level of education in the Netherlands.

This article is focused on financial-economic and socio-cultural factors in explaining differences in labour participation and working hours of Dutch mothers with diverging educational levels. The data used are taken from a survey held among approximately 1700 women in the Netherlands from two-parent households with children up to 12 years old. The models for participation and working hours are simultaneously estimated for different levels of education. It is found that socio-cultural factors have slightly more impact on the employment decisions of lower educated mothers compared to their higher educated counterparts, although the differences are only minor. Despite the level of education, socio-cultural factors appear to be more important in mothers' employment decisions than financial-economic factors. In addition, both factors are better predictors for mothers' decisions to participate than for their number of working hours; demographic variables are found to be the most important predictor for mothers' working hours. © The Author(s) 2011

Wage differentials and their determinants in US tourism and tourism-associated industries

This paper examines variations in wages for tourism related industries in the US for the period 2004-2009. It critically assesses the extent to which tourism related activities conform to their low wage stereotype and finds this to be true in general but not universally. It then considers the possibility that wages in US tourism related industries can be explained by observable characteristics of these industries. Recent research has suggested that the use of wage data at the level of highly detailed occupations is an effective alternative to other ways of capturing underlying skill differences. In line with this literature data from the US Occupational Employment Statistics (OES) were used to provide this detail. The results strongly support the importance of difference between occupations in wages in understanding differences between industries. They also support the importance of a number of industry characteristics including profitability, multi-factor productivity and demand growth. The paper also considers the relevance of an industry wage premium or discount for tourism related activities in the US over the same period. To assess this it estimates an industry wage model separately for five individual occupations across all industries which employ the occupation concerned. Within the small number of occupations covered the analysis find that workers in the two more highly paid occupations exhibit evidence of a tourism related discount but that workers in the three more lowly paid occupations exhibit a tourism related wage premium