Implementing Value-Added Models of School Assessment

This paper considers value-added models of school assessment and their implementation in Poland. Value-added estimates can be very helpful for schools and policy makers who need a reliable way to control teaching effectiveness, or for parents who need information about school quality in their area. However, their usefulness depends on several statistical issues and specific decisions made during implementation. The paper discusses several value-added models and describes details of the solution implemented in Poland. Statistical problems are discussed according to their policy relevance. It is shown that what bothers statisticians is less important in practice than several problems encountered when one wants to apply these models to a policy relevant context. Problems of proper regression specification, omitted variables bias, and measurement error are discussed, but the ways value-added estimates could be published and used as policy evaluation tools are also presented. All this problems are discussed from a practical point of view using three years of experience in implementation of these methods in Poland.education, school assessment, school effectiveness, value-added models

On Wiener-Hopf factors for stable processes

We give a series representation of the logarithm of the bivariate Laplace exponent $\kappa$ of $\alpha$-stable processes for almost all $\alpha \in (0,2]$.Comment: 16 pages. to appear in Annales IHP, 201

What works for disadvantaged unemployed : private or public ALMP services? Evidence from Poland

Purpose: This paper aims to assess the effectiveness of public vs. private active labour market policies (ALMP) for disadvantaged unemployed. The literature on the efficiency of contracting-out ALMP services by public institutions is not consistent. Formalism and limited scope of possible actions in public institutions stand in the way to activation of the less promising unemployed. On the other hand, contracted-out companies work as a black-box and are paid a success fee. Design/Methodology/Approach: We used (conducted by accident) Randomised Control Trial evaluation of the contracting-out ALMP services program in Poland. We used public registers data from Poland. Findings: We found a strong positive effect of support provided by contracted private agencies. This effect was found to be the strongest among the most dismissed groups of the unemployed. Practical Implications: Study shows that success-fee for external institutions and lack of hard frames assures incentives compatibility that results in real improvement of the unemployed situation, even a year after the end of the intervention. This conclusion should result in adjustments in active labour market policy. Originality/Value: The uniqueness of the study lies in scale of the RCT experiment and robustness of conculusons. The golden standard of evaluation allowed for gaining indisputable evidence on the effectiveness of particular ALMP instrument. Without this kind of analysis, public decisions can turn out to be wrong and lead to the closure of effective programmes (as it happened with contracting-out ALMP services), and investment in programmes that do not provide any effective support for those in need.peer-reviewe

On exit time of stable processes

We study the exit time $\tau=\tau_{(0,\infty)}$ for 1-dimensional strictly stable processes and express its Laplace transform at $t^\alpha$ as the Laplace transform of a positive random variable with explicit density. Consequently, $\tau$ satisfies some multiplicative convolution relations. For some stable processes, e.g. for the symmetric $\frac23$-stable process, explicit formulas for the Laplace transform and the density of $\tau$ are obtained as an application