Multi-Family Households in a Labour Supply Model: A Calibration Method with Application to Poland

The collective model of labour supply opened the household “black box” and allowed for individual treatment of partners in couples. However, the literature on labour supply has so far largely ignored a broader issue with special relevance to transition and developing countries – the distinction of single versus multi-family (“complex”) households. We propose a method to account for multi-family household structure by borrowing from recent applications of the collective model and combining estimation and calibration to identify the degree of resource sharing. We assume that each household is characterised by a between-family sharing parameter, which is calibrated on estimated preferences, the observed labour market status and other characteristics. The key identifying assumption is that preferences over income and leisure of specific family types living in single and multi-family households are the same conditional on observable characteristics. We apply the method to Polish labour market data.labour supply, within-household sharing, work incentives, transition

Dynamics of Poor Health and Non-Employment

While there is little doubt that the probability of poor health increases with age, and that less healthy people face a more difficult situation on the labour market, the precise relationship between facing the risks of health deterioration and labour market instability is not well understood. Using twelve years of data from the German Socio-Economic Panel we study the nature of the relationship between poor health and non-employment on a sample of German men aged 30-59. We propose to model poor health and non-employment as interrelated risks determined within a dynamic structure conditional on a set of individual characteristics. Applying dynamic panel estimation we identify the mechanism through which poor health contributes to the probability of being jobless and vice versa. We find an important role of unobserved heterogeneity and evidence for correlation in the unobservable characteristics determining the two processes. The results also show strong persistence in the dynamics of poor health and non-employment.risk, non-employment, health, ageing, dynamic panel data

Apply with Caution: Introducing UK-Style In-work Support in Germany

Estimates of labour supply effects of recent UK reforms in the area of direct taxes and benefits show that policy can have significant influence on the level of employment. We confirm this in a simulation of in-work support system introduced into the German tax and benefit system. Our simulation results suggest that introducing in-work Tax Credits in Germany would increase employment of single individuals by over 100,000 but it would result in a reduction of labour supply among individuals living in couples by about 70,000. We find that Tax Credits would result in significant reductions of labour supply both among women and men in two earner couples. The result found for men is especially important as it is markedly different from all results found for the UK, where the overall response among men has always been found positive. Our estimation results call for a high degree of caution as far as "importing" UK-style Tax Credits to Germany is concerned. In-work support based on family income would reinforce the existing work disincentives for secondary earners through joint income taxations, reducing the employment levels of both men and women living in couples.Tax-benefit system, In-work benefits, Microsimulation, Household labour supply

Extra mass flux in fluid mechanics

The conditions of existence of extra mass flux in single component dissipative non-relativistic fluids are clarified. By considering Galilean invariance we show that if total mass flux is equal to total momentum density, then mass, momentum, angular momentum and booster (center-of-mass) are conserved. However, these conservation laws may be fulfilled also by other means. We show an example of weakly non-local hydrodynamics where the conservation laws are satisfied as well although the total mass flux is different from momentum density

Percent level precision physics at the Tevatron: first genuine NNLO QCD corrections to q qbar -> t tbar + X

We compute the Next-to-Next-to-Leading Order (NNLO) QCD corrections to the partonic reaction that dominates top-pair production at the Tevatron. This is the first ever NNLO calculation of an observable with more than two colored partons, and/or massive fermions, at hadron colliders. Augmenting our fixed order calculation with soft-gluon resummation through Next-to-Next-to-Leading Logarithmic (NNLL) accuracy, we observe that the predicted total inclusive cross-section exhibits a very small perturbative uncertainty, estimated at +-2.7%. We expect that once all sub-dominant partonic reactions are accounted for, and work in this direction is ongoing, the perturbative theoretical uncertainty for this observable could drop below +-2%. Our calculation demonstrates the power of our computational approach and proves it can be successfully applied to all processes at hadron colliders for which high-precision analyses are needed.Comment: 4 pages, 4 figure

A simple parameter-free and adaptive approach to optimization under a minimal local smoothness assumption

We study the problem of optimizing a function under a \emph{budgeted number of evaluations}. We only assume that the function is \emph{locally} smooth around one of its global optima. The difficulty of optimization is measured in terms of 1) the amount of \emph{noise} $b$ of the function evaluation and 2) the local smoothness, $d$, of the function. A smaller $d$ results in smaller optimization error. We come with a new, simple, and parameter-free approach. First, for all values of $b$ and $d$, this approach recovers at least the state-of-the-art regret guarantees. Second, our approach additionally obtains these results while being \textit{agnostic} to the values of both $b$ and $d$. This leads to the first algorithm that naturally adapts to an \textit{unknown} range of noise $b$ and leads to significant improvements in a moderate and low-noise regime. Third, our approach also obtains a remarkable improvement over the state-of-the-art SOO algorithm when the noise is very low which includes the case of optimization under deterministic feedback ($b=0$). There, under our minimal local smoothness assumption, this improvement is of exponential magnitude and holds for a class of functions that covers the vast majority of functions that practitioners optimize ($d=0$). We show that our algorithmic improvement is borne out in experiments as we empirically show faster convergence on common benchmarks