In non-linear regression models, such as the probit model, coefficients cannot be interpreted as marginal effects. The marginal effects are usually non-linear combinations of all regressors and regression coefficients of the model. This paper derives the marginal effects in a probit model with a...

This paper analyzes the Steiner-Weber-Problem with piecewise linear or piecewise constant transportation costs. These non-differentiable cost functions are analyzed using different one-step and dynamic linearization methods, which are based on approximations via average and marginal costs. An...

This paper presents a linear programming approach to analyze and optimize flow lines with limited buffer capacities and stochastic processing times. The basic idea is to solve a huge but simple linear program that models an entire simulation run of a multi-stage production process in discrete...

This paper presents an optimization-based solution approach for the dynamic multi-level capacitated lot sizing problem (MLCLSP) with positive lead times. The key idea is to solve a series of mixed-integer programs in an iterative fix-and-optimize algorithm. Each of these programs is optimized...

This paper proposes a new unit root test against a non-linear exponential smooth transition autoregressive (ESTAR) model. The new test is build upon the non-standard testing approach of Abadir and Distaso (2007) who introduce a class of modified statistics for testing joint hypotheses when one...

In this paper, we analyze the performance of call centers of financial service providers with two levels of support and a time-dependent overflow mechanism. Waiting calls from the front-office queue flow over to the back office, if a waiting-time limit is reached and at least one back-office...

This paper presents a new algorithm for the dynamic Multi-Level Capacitated Lot Sizing Problem with Setup Carry-Overs (MLCLSP-L). The MLCLSP-L is a big-bucket model that allows the production of any number of products within a period, but it incorporates partial sequencing of the production...

This paper presents a new approach to obtain unbiased estimates of the value of a statistical life (VSL) with labor market data. Investigating job changes, we combine the advantages of recent panel studies, which allow to control for unobserved heterogeneity of workers, and conventional...

We propose a new methodology for comparing poverty over multiple periods across time and space that does not arbitrarily aggregate income over various years or rely on arbitrarily specified poverty lines or poverty indices. Following Duclos et al. (2006a), we use the multivariate stochastic...

We consider a model of a monopolistic network operator who sequentially offers two-parted access charges to symmetric downstream firms. We are particularly interested in analyzing an alternative to current regulatory practice of prescribing access. In particular, we look at the possibility of...