Attraction models used to analyse the effects of marketing instruments on market share hitherto assume certain strict functional forms. We introduce semiparametric models whose parametric components are equivalent to an exponential or multiplicative function. The nonparametric part is estimated...

We analyze simultaneous discrete public good games with incomplete information and continuous contributions. To use the terminology of Admati and Perry (1991), we consider contribution and subscription games. In the former, contributions are not refunded if the project is not completed, while in...

We consider a rectangular Vandermonde matrix on Chebyshev nodes. Using combinatorial identities, we give an explicit factorization of the matrix , a factorization of the pseudo-inverse of , and prove that the condition number () does not depend on the dimension of nodes set. We also discuss the...

We have studied a series of (ansätze) ordinary differential equations of the first-order, which correspond to the travelling (and/or solitary) wave solutions of some nonlinear partial differential equations. We have investigated the conditions, under which the nonlinear partial differential...

We treat the n-job, two-stage hybrid flowshop problem with one machine in the first stage and two different machines in parallel in the second stage. The objective is to minimize the makespan. We demonstrate that the problem is NP-complete. We formulate a dynamic program, which is beyond our...

The movement of the human body is simulated with a virtual, mechanical, robot-type model (articulated figure) consisting of 14 solid subbodies. The shapes of these 14 subbodies are initially a ball, cylinders or rectangular boxes. The model is initially adapted, in particular the dimensions of...

A formula for evaluation of the distribution of a linear combination of independent inverted gamma random variables by one-dimensional numerical integration is presented. The formula is direct application of the inversion formula given by Gil-Pelaez (1951). This method is applied to computation...

We extend the results of the authors in [., (1998) 101-134] on the convergence of genetic algorithms with proportional fitness-scaled selection to genetic algorithms with various types of tournament fitness selection often used in practical applications. Our analysis allows for a general notion...

We consider the problem of minimizing a supermodular set function whose special case is the well-known NP-hard -median problem. The main result of the paper is a tight bound on the approximation ratio of a greedy heuristic (discrete analog of the steepest descent algorithm) for this problem