Does the Hartz IV Reform have an Effect on Matching Efficiency in Germany? A Stochastic Frontier Approach

In the course of a comprehensive labor market reform started in 2002 and finished through the implementation of the most radical measure Hartz IV in 2005, I exploit its impact on matching processes in Germany. I use disaggregated data for 178 local employment agencies to examine the effects of stocks and flows of vacancies and unemployed on the hiring rate as well as on the matching efficiency. Building on the work of Ibourk et al. (2004) and Fahr and Sunde (2006), I employ a stochastic frontier analysis. As a functional framework I choose the translog function to address the interactions of stocks and flows in generating new hires. Furthermore, the twofold structure of a stochastic frontier allows for a modeling of potential sources (e.g. Hartz IV) expected to induce an increased or decreased matching efficiency. My results suggest that Hartz IV exhibits a significantly positive impact on the hiring rate and the matching efficiency. Compared to 1998, on average matching efficiency experienced an increase in 2007

Global supply chains of high value low volume products

Imperial Users onl

Reliability-based economic model predictive control for generalized flow-based networks including actuators' health-aware capabilities

This paper proposes a reliability-based economic model predictive control (MPC) strategy for the management of generalized flow-based networks, integrating some ideas on network service reliability, dynamic safety stock planning, and degradation of equipment health. The proposed strategy is based on a single-layer economic optimisation problem with dynamic constraints, which includes two enhancements with respect to existing approaches. The first enhancement considers chance-constraint programming to compute an optimal inventory replenishment policy based on a desired risk acceptability level, leading to dynamically allocate safety stocks in flow-based networks to satisfy non-stationary flow demands. The second enhancement computes a smart distribution of the control effort and maximises actuators’ availability by estimating their degradation and reliability. The proposed approach is illustrated with an application of water transport networks using the Barcelona network as the considered case study.Peer ReviewedPostprint (author's final draft

Self-Evaluation Applied Mathematics 2003-2008 University of Twente

This report contains the self-study for the research assessment of the Department of Applied Mathematics (AM) of the Faculty of Electrical Engineering, Mathematics and Computer Science (EEMCS) at the University of Twente (UT). The report provides the information for the Research Assessment Committee for Applied Mathematics, dealing with mathematical sciences at the three universities of technology in the Netherlands. It describes the state of affairs pertaining to the period 1 January 2003 to 31 December 2008

Environmental efficiency : meaning and measurement and application to Australian dairy farms

Technical efficiency has been widely studied in the literature, but in its pursuit, many of the inputs used can impact on the environment. Environmental effects can be modelled as undesirable output or, as has been the case in more recent studies, as conventional inputs. This paper examines the concept of environmental efficiency and how it can be used to evaluate the performance of Australian dairy farming, using nitrogen surplus, arising from excessive applications of fertilizer, as a detrimental input. Farming promotes the image of clean and green production and if this image is to be maintained, there is a need to ensure activities are environmentally friendly.<br /

International Trade Efficiency, the Gravity Equation, and the Stochastic Frontier

In the gravity equation of international trade, bilateral trade flows are regressed on trading partners’ income and the distance that separates them along with other variables. This widely used equation is traditionally estimated by the ordinary least squares method. We employ an alternative technique of stochastic frontier estimation to assess the potential bilateral trade flows from the same gravity equation. Countries are shown to have low efficiencies in their international trade as the predicted trade from frontier estimation is generally far greater than actual trade. Trade efficiencies are computed and ranked for individual countries, ten geographical regions, and eleven regional trade agreements.efficiency coefficients, OLS residuals, trade gravity, trade potentials