In this report, we develop a procedure to analyze the relationship between the observed multi-dimensional counts and a set of explanatory variables. The counts follow a multivariate Poisson distribution or a multivariate zero-inflated Poisson distribution. Maximum likelihood estimates (MLE) for the model parameters are obtained by the Newton-Raphson (NR) iteration and the expectation-maximizati...

Restricted Maximum Likelihood estimation using first and second derivatives of the likelihood is described. It relies on the calculation of derivatives without the need for large matrix inversion using an automatic differentiation procedure. In essence, this is an extension of the Cholesky factorisation of a matrix. A reparameterisation is used to transform the constrained optimisation problem ...

Models for multiphase-multicomponent flow in porous media are described in systems of PDEs. Solving them using finite difference discretization method can be of three ways; explicit, semi-implicit, and fully implicit. In this study, we present the implementation of an adaptive Newton-Raphson method in the context of IMPECS (Implicit Pressures Explicit Concentrations and Saturations) method of s...

Newton-Raphson State Estimation method using bus admittance matrix remains as an efficient and most popular method to estimate the state variables. Elements of Jacobian matrix are computed from standard expressions which lack physical significance. In this paper, elements of the state estimation Jacobian matrix are obtained considering the power flow measurements in the network elements. These ...

Over the past years there has been considerable interest in statistically optimal reconstruction of cross-sectional images from tomographic data. In particular, a variety of such algorithms have been proposed for maximum a posteriori (MAP) reconstruction from emission tomographic data. While MAP estimation requires the solution of an optimization problem, most existing reconstruction algorithms...

Steady state analysis of a 3-φ SEIG is generally done through mathematical modeling of its equivalent circuit. The impedance model can be reduced in terms of two nonlinear simultaneous equations consisting of unspecified variables as magnetizing reactance Xm and generated frequency F. The steady state performance analysis of SEIG becomes uncomplicated once the values of Xm and F are explicitly ...

The DC operating point of an electronic circuit is conventionally found using the NewtonRaphson method. This method is not globally convergent and can only find one solution of the circuit at a time. In this paper, evolutionary computing methods, including Genetic Algorithms, Evolutionary Programming, Evolutionary Strategies and Differential Evolution are explored as possible alternatives to Ne...