SubCMap: subject and condition specific effect maps

Current methods for statistical analysis of neuroimaging data identify condition related structural alterations in the human brain by detecting group differences. They construct detailed maps showing population-wide changes due to a condition of interest. Although extremely useful, methods do not provide information on the subject-specific structural alterations and they have limited diagnostic value because group assignments for each subject are required for the analysis. In this article, we propose SubCMap, a novel method to detect subject and condition specific structural alterations. SubCMap is designed to work without the group assignment information in order to provide diagnostic value. Unlike outlier detection methods, SubCMap detections are condition-specific and can be used to study the effects of various conditions or for diagnosing diseases. The method combines techniques from classification, generalization error estimation and image restoration to the identify the condition-related alterations. Experimental evaluation is performed on synthetically generated data as well as data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Results on synthetic data demonstrate the advantages of SubCMap compared to population-wide techniques and higher detection accuracy compared to outlier detection. Analysis with the ADNI dataset show that SubCMap detections on cortical thickness data well correlate with non-imaging markers of Alzheimer's Disease (AD), the Mini Mental State Examination Score and Cerebrospinal Fluid amyloid-β levels, suggesting the proposed method well captures the inter-subject variation of AD effects

Learning to Detect and Track Cells for Quantitative Analysis of Time-Lapse Microscopic Image Sequences

© 2015 IEEE.Studying the behaviour of cells using time-lapse microscopic imaging requires automated processing pipelines that enable quantitative analysis of a large number of cells. We propose a pipeline based on state-of-the-art methods for background motion compensation, cell detection, and tracking which are integrated into a novel semi-automated, learning based analysis tool. Motion compensation is performed by employing an efficient nonlinear registration method based on powerful discrete graph optimisation. Robust detection and tracking of cells is based on classifier learning which only requires a small number of manual annotations. Cell motion trajectories are generated using a recent global data association method and linear programming. Our approach is robust to the presence of significant motion and imaging artifacts. Promising results are presented on different sets of in-vivo fluorescent microscopic image sequences

Expected Future Earnings, Taxation, and University Enrollment: A Microeconometric Model with Uncertainty

Taxation changes the expectations of prospective university students about their future level and uncertainty of after-tax income. To estimate the impact of taxes on university enrollment, we develop and estimate a structural microeconometric model, in which a high-school graduate decides to enter university studies if expected lifetime utility from this choice is greater than that anticipated from starting to work right away. We estimate the ex-ante future paths of the expectation and variance of net income for German high-school graduates, using only information available to those graduates at the time of the enrollment decision, accounting for multiple nonrandom selection and employing a microsimulation model to account for taxation. In addition to income uncertainty, the enrollment model takes into account university dropout and unemployment risks, as well as potential credit constraints. The estimation results are consistent with expectations. First, higher risk-adjusted returns to an academic education increase the probability of university enrollment. Second, high-school graduates are moderately risk averse, as indicated by the Arrow-Pratt coefficient of risk aversion estimated within the model. Thus, higher uncertainty among academics decreases enrollment rates. A simulation based on the estimated structural model indicates that a revenue-neutral, flat-rate tax reform with an unchanged basic tax allowance would increase enrollment rates for men in Germany because of the higher expected net income in the higher income range.University Enrollment, Income Taxation, Flat Tax, Income Risk, Risk Aversion

Self-Employment - a Way to End Unemployment?: Empirical Evidence from German Pseudo-Panel Data

This paper contributes to the policy-relevant question whether self-employment is a way out of (long-term) unemployment. We estimate the relationship between the entry rate into self-employment and previous (long-term) unemployment on the basis of pseudo-panel data for Germany in the period 1996-2002. The estimation method accounts for cohort fixed effects and measurement errors induced by the pseudo panel structure. We find that previous (long-term) unemployment significantly increases entry rates into self-employment for both men and women. These effects are quantitatively important, both in absolute terms and compared to other potential determinants of self-employment transitions, such as age, the level of vocational qualification and certain household characteristics.self-employment, entrepreneurship, entry rate, start-ups, unemployment, pseudo-panel, age and cohort effects

Reserve Requirements for Price and Financial Stability - When Are They Effective?

Reserve requirements are a prominent policy instrument in many emerging countries. The present study investigates the circumstances under which reserve requirements are an appropriate policy tool for price or financial stability. We consider a small open economy model with sticky prices, financial frictions and a banking sector that is subject to legal reserve requirements and compute optimal interest rate and reserve requirement rules. Overall, our results indicate that reserve requirements can support the price stability objective only if financial frictions are important and lead to substantial improvements if there is a financial stability objective. Contrary to a conventional interest rate policy, reserve requirements become more effective when there is foreign currency debt.Reserve Requirements, Monetary Policy, Financial Stability, Capital Flows, Business Cycle.

Returns to education across Europe: A comparative analysis for selected EU countries

Incentives to invest in higher education are affected by both the direct wage effect of human capital investments and the indirect wage effect resulting from lower unemployment risks and shorter spells in unemployment associated with higher educated. We analyse the returns to education in Austria, Germany, Italy, Sweden and the United Kingdom, countries which differ significantly regarding both their education systems and labour market structure. We estimate augmented Mincerian wage equations accounting for the effects of unemployment on individual wages using EU-SILC data. Across countries we find a high variation of the effect of education on unemployment duration. Overall, the returns to education are estimated to be the highest in the UK, and the lowest for Sweden. A wage decrease due to time spent in unemployment results in a decline in the hourly wages in Austria, Germany and Italy. --Returns to education,unemployment,EU-SILC

Unemployment compensation and aggregate fluctuations

This paper focuses on a theoretical and empirical analysis of the effects of discretionary changes of unemployment compensation payments on aggregate fluctuations. By means of a dynamic stochastic general equilibrium model, it is shown that unemployment compensation can stabilize consumption on the one hand; however, on the other one, it has adverse effects on unemployment and output. These theoretical results are confirmed by the empirical structural vector autoregressive model. Moreover, the results highlight the importance of real wages in transmitting unemployment benefit shocks on to the macroeconomy. In particular, discretionary changes lead to an increase in real wages, unemployment and consumption while inducing a small decline in outpu