A novel hybrid evolutionary algorithm is developed based on the particle swarm optimization (PSO) and genetic algorithms (GAs). The PSO phase involves the enhancement of worst solutions by using the global-local best inertia weight and acceleration coefficients to increase the efficiency. In the...

Multiple choice items on tests and Likert items on surveys are ubiquitous in educational, social and behavioral science research; however, methods for analyzing of such data can be problematic. Multidimensional item response theory models are proposed that yield structured Poisson regression...

In this working paper we study some properties of a particular mapping in Rn related to an optimization problem with one equality constraint. We motivate the definition of the relevant mapping starting from a portfolio selection problem, in which we minimize the risk of an investment (the...

Impulsive control consideres so called interventions meaning immediate change of the state of the system; between intervention, the continuous time jump Markov process is uncontrollable, with “natural” jump intensities. Multicriteria control problem for such model is considered, and the...

Professional economists rarely write on questions of genocide. This surprises because a workhorse tool of the economics discipline concerns the analysis of behavior that takes place under constraints. All parties in genocide—perpetrators, victims, and third parties—face cost and resource...

We consider some asymptotic distribution theory for M-estimators of the parameters of a linear model whose errors are non-negative; these estimators are the solutions of constrained optimization problems and their asymptotic theory is non-standard. Under weak conditions on the distribution of the...

Crop rotations are known to have two main kinds of economic effects: direct effects on potential yields and on the productivity of different inputs, and indirect effects on economically optimal input levels, especially pesticides and fertilizers. The main objective of this article is to uncover...

This paper studies first-order differentiability properties of the value function in concave dynamic programs. Motivated by economic considerations, we dispense with commonly imposed interiority assumptions. We suppose that the correspondence of feasible choices varies with the vector of state...