Pareto-Improving Optimal Capital and Labor Taxes

We study Pareto-optimal scal policy in a model with agents who are heterogeneous in their labor productivity and wealth. We show a natural modi cation of the standard Ramsey problem to guarantee that long-run capital taxes are zero. We focus on Paretoimproving policies and we nd that a gradual reform is crucial in achieving a Pareto improvement: labor taxes should be cut and capital taxes should remain high for a very long time before reaching zero. Therefore, the long-run optimal tax mix is the opposite of the short- and medium-run one. This policy redistributes wealth in favor of workers so that all agents bene t, and it favors quick capital growth after the reform. The labor tax cut is nanced by de cits which lead to a positive level of government debt in the long run, reversing the standard prediction that the government accumulates savings in models with optimal capital taxes. The welfare bene ts from the tax reform are relatively large and they can be shifted entirely to capitalists or workers by varying the length of the transition. We address a number of technical issues such as su ciency of Lagrangian solutions in a Ramsey problem, relation of Pareto-improving allocations with welfare functions, asymptotic behavior, and solution algorithms

Pediatric Bone Age Assessment Using Deep Convolutional Neural Networks

Skeletal bone age assessment is a common clinical practice to diagnose endocrine and metabolic disorders in child development. In this paper, we describe a fully automated deep learning approach to the problem of bone age assessment using data from Pediatric Bone Age Challenge organized by RSNA 2017. The dataset for this competition is consisted of 12.6k radiological images of left hand labeled by the bone age and sex of patients. Our approach utilizes several deep learning architectures: U-Net, ResNet-50, and custom VGG-style neural networks trained end-to-end. We use images of whole hands as well as specific parts of a hand for both training and inference. This approach allows us to measure importance of specific hand bones for the automated bone age analysis. We further evaluate performance of the method in the context of skeletal development stages. Our approach outperforms other common methods for bone age assessment.Comment: 14 pages, 9 figure

Mixed population of competing TASEPs with a shared reservoir of particles

We introduce a mean-field theoretical framework to describe multiple totally asymmetric simple exclusion processes (TASEPs) with different lattice lengths, entry and exit rates, competing for a finite reservoir of particles. We present relations for the partitioning of particles between the reservoir and the lattices: these relations allow us to show that competition for particles can have non-trivial effects on the phase behavior of individual lattices. For a system with non-identical lattices, we find that when a subset of lattices undergoes a phase transition from low to high density, the entire set of lattice currents becomes independent of total particle number. We generalize our approach to systems with a continuous distribution of lattice parameters, for which we demonstrate that measurements of the current carried by a single lattice type can be used to extract the entire distribution of lattice parameters. Our approach applies to populations of TASEPs with any distribution of lattice parameters, and could easily be extended beyond the mean-field case.Comment: 12 pages, 8 figure

Single-Bottleneck Approximation for Driven Lattice Gases with Disorder and Open Boundary Conditions

We investigate the effects of disorder on driven lattice gases with open boundaries using the totally asymmetric simple exclusion process as a paradigmatic example. Disorder is realized by randomly distributed defect sites with reduced hopping rate. In contrast to equilibrium, even macroscopic quantities in disordered non-equilibrium systems depend sensitively on the defect sample. We study the current as function of the entry and exit rates and the realization of disorder and find that it is, in leading order, determined by the longest stretch of consecutive defect sites (single-bottleneck approximation, SBA). Using results from extreme value statistics the SBA allows to study ensembles with fixed defect density which gives accurate results, e.g. for the expectation value of the current. Corrections to SBA come from effective interactions of bottlenecks close to the longest one. Defects close to the boundaries can be described by effective boundary rates and lead to shifts of the phase transitions. Finally it is shown that the SBA also works for more complex models. As an example we discuss a model with internal states that has been proposed to describe transport of the kinesin KIF1A.Comment: submitted to J. Stat. Mec

Comparison of two devices and two breathing patterns for exhaled breath condensate sampling.

Analysis of exhaled breath condensate (EBC) is a noninvasive method to access the epithelial lining fluid of the lungs. Due to standardization problems the method has not entered clinical practice. The aim of the study was to assess the comparability for two commercially available devices in healthy controls. In addition, we assessed different breathing patterns in healthy controls with protein markers to analyze the source of the EBC. EBC was collected from ten subjects using the RTube and ECoScreen Turbo in a randomized crossover design, twice with every device--once in tidal breathing and once in hyperventilation. EBC conductivity, pH, surfactant protein A, Clara cell secretory protein and total protein were assessed. Bland-Altman plots were constructed to display the influence of different devices or breathing patterns and the intra-class correlation coefficient (ICC) was calculated. The volatile organic compound profile was measured using the electronic nose Cyranose 320. For the analysis of these data, the linear discriminant analysis, the Mahalanobis distances and the cross-validation values (CVV) were calculated. Neither the device nor the breathing pattern significantly altered EBC pH or conductivity. ICCs ranged from 0.61 to 0.92 demonstrating moderate to very good agreement. Protein measurements were greatly influenced by breathing pattern, the device used, and the way in which the results were reported. The electronic nose could distinguish between different breathing patterns and devices, resulting in Mahalanobis distances greater than 2 and CVVs ranging from 64% to 87%. EBC pH and (to a lesser extent) EBC conductivity are stable parameters that are not influenced by either the device or the breathing patterns. Protein measurements remain uncertain due to problems of standardization. We conclude that the influence of the breathing maneuver translates into the necessity to keep the volume of ventilated air constant in further studies

On the segmentation and classification of hand radiographs

This research is part of a wider project to build predictive models of bone age using hand radiograph images. We examine ways of finding the outline of a hand from an X-ray as the first stage in segmenting the image into constituent bones. We assess a variety of algorithms including contouring, which has not previously been used in this context. We introduce a novel ensemble algorithm for combining outlines using two voting schemes, a likelihood ratio test and dynamic time warping (DTW). Our goal is to minimize the human intervention required, hence we investigate alternative ways of training a classifier to determine whether an outline is in fact correct or not. We evaluate outlining and classification on a set of 1370 images. We conclude that ensembling with DTW improves performance of all outlining algorithms, that the contouring algorithm used with the DTW ensemble performs the best of those assessed, and that the most effective classifier of hand outlines assessed is a random forest applied to outlines transformed into principal components

The Subjective Cost of Young Children: A European Comparison

Understanding child-related costs is crucial given their impact on fertility and labour supply decisions. We quantify and compare the cost of children in Europe by analysing the effect of child births on parents’ self-reported ability to make ends meet. This study is based on EUSILC longitudinal data for 30 European countries from 2004 to 2015, enabling comparisons between country groups of different welfare regimes. Results show that newborns decrease subjective economic wellbeing in all regions, yet with economies of scale in the number of children. The drop is mainly caused by increased expenses due to the birth of a child (direct costs), which are largest in high-income regions. Immediate labour income losses of mothers (indirect costs) are less important in explaining the decrease. These income losses are closely related to the employment patterns of mothers and are highest in regions where women take extensive parental leave. In the first years after the birth, indirect costs are mostly compensated for via public transfers or increased labour income of fathers, while direct costs of children are not compensated for

The subjective cost of young children: A European comparison

Understanding child-related costs is crucial given their impact on fertility and labour supply decisions. We quantify and compare the cost of children in Europe by analysing the effect of child births on parents’ self-reported ability to make ends meet. This study is based on EU- SILC longitudinal data for 30 European countries from 2004 to 2015, enabling comparisons between country groups of different welfare regimes. Results show that newborns decrease subjective economic wellbeing in all regions, yet with economies of scale in the number of children. The drop is mainly caused by increased expenses due to the birth of a child (direct costs), which are largest in high-income regions. Immediate labour income losses of mothers (indirect costs) are less important in explaining the decrease. These income losses are closely related to the employment patterns of mothers and are highest in regions where women take extensive parental leave. In the first years after the birth, indirect costs are mostly compensated for via public transfers or increased labour income of fathers, while direct costs of children are not compensated for