Showing 51 - 60 of 706
In this paper, we develop various calculus rules for general smooth matrix-valued functions and for the class of matrix convex (or concave) functions first introduced by Loewner and Kraus in 1930s. Then we use these calculus rules and the matrix convex function -log X to study a new notion of...
Persistent link: https://www.econbiz.de/10004969823
The lack of trust in the maritime industry between all the industry organizations and regulators has created an inspection industry which is heavily controlled by oil majors in order to limit their liability. This report is an introductory part of a PhD project called "The Econometrics of...
Persistent link: https://www.econbiz.de/10004969824
In this paper we consider a two-dimensional cutting stock problem encountered at a large manufacturer of window covering products. The problem occurs in the production process of made-to-measure roller blinds. We develop a solution method that takes into account the characteristics of the...
Persistent link: https://www.econbiz.de/10004969825
We study the performance of alternative sampling methods for estimating multivariate normal probabilities through the GHK simulator. The sampling methods are randomized versions of some quasi-Monte Carlo samples (Halton, Niederreiter, Niederreiter-Xing sequences and lattice points) and some...
Persistent link: https://www.econbiz.de/10004969826
In this paper we investigate how two online services (a portal and a digital library) may influence the adoption of an innovation. It is known from prior surveys that the installation services branch of the Dutch building industry has a relatively slow adoption rate for innovations. We examine...
Persistent link: https://www.econbiz.de/10004969827
Jan Tinbergen was the first Nobel Laureate in Economics in 1969. This paper presents a brief survey of his many contributions to economics, in particular to macro-econometric modelling, business cycle analysis, economic policy making, development economics, income distribution, international...
Persistent link: https://www.econbiz.de/10004972176
We discuss how prior regression on seasonal dummies leads to singularities in periodogram regression procedures for the detection of long memory. We suggest a modified procedure. We illustrate the problems using monthly inflation data from Hassler and Wolters (1995).
Persistent link: https://www.econbiz.de/10004972178
Our aim is to give a simple view on the basics and applications of convex analysis. The essential feature of this account is the systematic use of the possibility to associate to each convex object---such as a convex set, a convex function or a convex extremal problem--- a cone, without loss of...
Persistent link: https://www.econbiz.de/10004972179
Most maintenance-optimisation models assume an infinite planning horizon and suppose that the failure process is stationary. Hence, information which is not known beforehand and which becomes available on the short term only, must be ignored. We consider in this paper a multi-component system...
Persistent link: https://www.econbiz.de/10004972180
This paper reports on simulation results for the Wald test for ï¡1=ï¡2=0 in the regression model for the case ï« is known and for the case where ï« has to be estimated using nonlinear least squares (NLS). This last situation is not standard, and we therefore provide critical values for...
Persistent link: https://www.econbiz.de/10004972182