The initial size of a completely susceptible population in a group of individuals plays a key role in drawing inferences for epidemic models. However, this can be difficult to obtain in practice because, in any population, there might be individuals who may not transmit the disease during the epidemic. This short note describes how to improve the maximum likelihood estimators of the infection r...

This study introduces the concept of “attitude strength” to explain why some IT users’ attitudes are not strongly related to their usage behaviors. We review the attitude strength literature, employ the elaboration likelihood model to theorize personal relevance and related expertise as two salient dimensions of attitude strength in the IT usage context, and postulate a research model to captur...

In the previous lecture the detection of deterministic signals was dealt with. In this lecture, the focus will be on deciding between signals that are known except for a set of unknown random parameters. For this situation the hypothesis testing problem can be conveniently written as, (1) where Θ is an unknown parameter taking values from a parameter set Λ. Density of Θ is ω j under the hypothe...

In many causal inference problems, one is interested in the direct causal effect of an exposure on an outcome of interest that is not mediated by certain intermediate variables. Robins and Greenland (1992) and Pearl (2001) formalized the definition of two types of direct effects (natural and controlled) under the counterfactual framework. The efficient scores (under a nonparametric model) for t...

Three methods in common use for finding confidence regions for the parameters of a nonlinear regression model are studied. These are the lack of fit method, the linearization method, and the maximum likelihood method. The objective is to determine which of the three methods is the preferred choice in applications. The conclusion is that the linearization method has the best structural character...

The assignment of personal probabilities to form a forensic practitioner's likelihood ratio is a mental operation subject to all the frailties of human memory, perception and judgment. While we agree that beliefs expressed as coherent probabilities are neither 'right' nor 'wrong' we argue that debate over this fact obscures both the requirement for and consideration of the 'helpfulness' of prac...

Matched case-control study designs are commonly implemented in the field of public health. While matching is intended to eliminate confounding, the main potential benefit of matching in case-control studies is a gain in efficiency. Methods for analyzing matched case-control studies have focused on utilizing conditional logistic regression models that provide conditional and not causal estimates...

It is often desirable to separate voxels that contain signal from tissue along with measurement noise from those that contain purely measurement noise. Generally, this separation called thresholding utilizes only the magnitude portion of the images. Recently, methods have been developed that utilize both the magnitude and phase for thresholding voxels. This manuscript is an extension previous w...

Probabilistic methods involving maximum-likelihood parameter estimation have become a powerful tool in computational crystallography. At the centre of these methods are the relevant probability distributions. Here, equations are developed based on the complex multivariate normal distribution that generalize the distributions currently used in maximum-likelihood model and heavy-atom refinement. ...

Although single-species deterministic difference equations have long been used in modeling the dynamics of animal populations, little attention has been paid to how stochasticity should be incorporated into these models. By deriving stochastic analogues to difference equations from first principles, we show that the form of these models depends on whether noise in the population process is demo...