Non-response in the American Time Use Survey: Who Is Missing from the Data and How Much Does It Matter?

This paper examines non-response in a large government survey. The response rate for the American Time Use Survey (ATUS) has been below 60 percent for the first two years of its existence, raising questions about whether the results can be generalized to the target population. The paper begins with an analysis of the types of non-response encountered in the ATUS. We find that non-contact accounts for roughly 60 percent of ATUS non-response, with refusals accounting for roughly 40 percent. Next, we examine two hypotheses about the causes of this non-response. We find little support for the hypothesis that busy people are less likely to respond to the ATUS, but considerable support for the hypothesis that people who are weakly integrated into their communities are less likely to respond, mostly because they are less likely to be contacted. Finally, we compare aggregate estimates of time use calculated using the ATUS base weights without any adjustment for non-response to estimates calculated using the ATUS final weights with a non-response adjustment and to estimates calculated using weights that incorporate our own non-response adjustments based on a propensity model. While there are some modest differences, the three sets of estimates are broadly similar. The paper ends with a discussion of survey design features, their effect on the types and level of non-response, and the tradeoffs associated with different design choices.

A Cross-National Look at Married Women's Economic Dependency

Using the LIS data, the authors examine married women's dependency on their husbands' earnings in nine Western industrialized countries: Australia; Belgium; Canada; Finland; Germany; Netherlands; Norway; Sweden; and the United States. When we examine the level and degree of dependency, and the labor force participation of married women, the nine countries cluster in three groups along the lines of the Esping-Anderson welfare state typology. But when we examine the determinants of the dependency within each country, the clustering disappears. Wives' dependency increases with age, the presence of young children, and the number of children. It is reduced when wives' labor force participation and education are high relative to their husbands and in families which rely more on unearned sources of income. The similarity of patterns across countries suggests that gender differences in the work-family nexus are deeply entrenched in all countries and continue even in the face of very active social policy to minimize their effects

Radiative equilibrium in Monte Carlo radiative transfer using frequency distribution adjustment

The Monte Carlo method is a powerful tool for performing radiative equilibrium calculations, even in complex geometries. The main drawback of the standard Monte Carlo radiative equilibrium methods is that they require iteration, which makes them numerically very demanding. Bjorkman & Wood recently proposed a frequency distribution adjustment scheme, which allows radiative equilibrium Monte Carlo calculations to be performed without iteration, by choosing the frequency of each re-emitted photon such that it corrects for the incorrect spectrum of the previously re-emitted photons. Although the method appears to yield correct results, we argue that its theoretical basis is not completely transparent, and that it is not completely clear whether this technique is an exact rigorous method, or whether it is just a good and convenient approximation. We critically study the general problem of how an already sampled distribution can be adjusted to a new distribution by adding data points sampled from an adjustment distribution. We show that this adjustment is not always possible, and that it depends on the shape of the original and desired distributions, as well as on the relative number of data points that can be added. Applying this theorem to radiative equilibrium Monte Carlo calculations, we provide a firm theoretical basis for the frequency distribution adjustment method of Bjorkman & Wood, and we demonstrate that this method provides the correct frequency distribution through the additional requirement of radiative equilibrium. We discuss the advantages and limitations of this approach, and show that it can easily be combined with the presence of additional heating sources and the concept of photon weighting. However, the method may fail if small dust grains are included... (abridged)Comment: 17 pages, 2 figures, accepted for publication in New Astronom

What Effects Do Macroeconomic Conditions Have on Families’ Time Together?

We examine family time together using data from the 2003-2010 American Time Use Survey combined with Bureau of Labor Statistics data on state-level unemployment rates. Couple time together is U-shaped; while fathers spend more time engaging in enriching childcare activities without a spouse present as the unemployment rate rises. Patterns are similar for dual-earner couples, but appear concentrated among demographic groups most affected by recessions. We also find that mothers are less likely to work standard hours and more likely to work on weekends as employment crises deepen, which is consistent with both sets of results for family time together

High-resolution, 3D radiative transfer modelling : V. A detailed model of the M 51 interacting pair

Context. Investigating the dust heating mechanisms in galaxies provides a deeper understanding of how the internal energy balance drives their evolution. Over the last decade radiative transfer simulations based on the Monte Carlo method have emphasised the role of the various stellar populations heating the diffuse dust. Beyond the expected heating through ongoing star formation, older stellar populations (>= 8 Gyr) and even active galactic nuclei can both contribute energy to the infrared emission of diffuse dust.Aims. In this particular study we examine how the radiation of an external heating source, such as the less massive galaxy NGC 5195 in the M 51 interacting system, could affect the heating of the diffuse dust of its parent galaxy NGC 5194, and vice versa. Our goal is to quantify the exchange of energy between the two galaxies by mapping the 3D distribution of their radiation field.Methods. We used SKIRT, a state-of-the-art 3D Monte Carlo radiative transfer code, to construct the 3D model of the radiation field of M 51, following the methodology defined in the DustPedia framework. In the interest of modelling, the assumed centre-to-centre distance separation between the two galaxies is similar to 10 kpc.Results. Our model is able to reproduce the global spectral energy distribution of the system, and it matches the resolved optical and infrared images fairly well. In total, 40.7% of the intrinsic stellar radiation of the combined system is absorbed by dust. Furthermore, we quantify the contribution of the various dust heating sources in the system, and find that the young stellar population of NGC 5194 is the predominant dust-heating agent, with a global heating fraction of 71.2%. Another 23% is provided by the older stellar population of the same galaxy, while the remaining 5.8% has its origin in NGC 5195. Locally, we find that the regions of NGC 5194 closer to NGC 5195 are significantly affected by the radiation field of the latter, with the absorbed energy fraction rising up to 38%. The contribution of NGC 5195 remains under the percentage level in the outskirts of the disc of NGC 5194. This is the first time that the heating of the diffuse dust by a companion galaxy is quantified in a nearby interacting system

Female Labor Supply Differences by Sexual Orientation: A Semi-Parametric Decomposition Approach

Using 2000 U.S. Census data we illustrate the importance of accounting for household specialization in lesbian couples when examining the sexual orientation gap in female labor supply. Specifically, we find the labor supply gap is substantially larger between married women and partnered lesbian women who specialize in market production (primary earners) than between married women and partnered lesbian women who specialize in household production (secondary earners). Using a semi-parametric decomposition approach, we further show that the role of children in explaining the mean labor supply gap by sexual orientation is greatly understated if the household division of labor between household and market production is not taken into account. Finally, we illustrate that controlling for children significantly reduces differences between married women and secondary lesbian earners both in terms of the decision to remain attached to the labor market (the extensive margin), as well as in terms of annual hours of work conditional on working (the intensive margin). Further, the effect of controlling for children is not uniform across the distribution of conditional annual hours; instead it primarily reduces the percentage of secondary lesbian earners working extremely high annual hours

The Ups and Downs in Women's Employment: Shifting Composition or Behavior from 1970 to 2010?

This paper tracks factors contributing to the ups and downs in women’s employment from 1970 to 2010 using regression decompositions focusing on whether changes are due to shifts in the means (composition of women) or due to shifts in coefficients (inclinations of women to work for pay). Compositional shifts in education exerted a positive effect on women’s employment across all decades, while shifts in the composition of other family income, particularly at the highest deciles, depressed married women’s employment over the 1990s contributing to the slowdown in this decade. A positive coefficient effect of education was found in all decades, except the 1990s, when the effect was negative, depressing women’s employment. Further, positive coefficient results for other family income at the highest deciles bolstered married women’s employment over the 1990s. Models are run separately for married and single women demonstrating the varying results of other family income by marital status. This research was supported in part by an Upjohn Institute Early Career Research Award

Persistence of Monopoly and Research Specialization

We examine the persistence of monopolies in markets with innovations when the outcome of research is uncertain. We show that for low success probabilities of research, the incumbent can seldom preempt the potential entrant. Then the efficiency effect outweighs the replacement effect. It is vice versa for high probabilities. Moreover, the incumbent specializes in safe research and the potential entrant in risky research. We also show that the probability of entry has an inverted U-shape in the success probability. Since even at the peak entry is rather unlikely, the persistence of the monopoly is high