Based on the Q-function, the conditional expectation of the logarithm of the jointlikelihood between responses and random effects, we propose a case-deletion approach to identify influential subjects and influential observations in linear mixed models. The models considered here are very broad in the sense that any covariance structures can be specified in the covariance matrices of the random ...

The purpose of this study is to evaluate the efficiency indices for 60 Brazilian electricity distribution utilities. These scores are obtained by DEA Data Envelopment Analysis and Bayesian Stochastic Frontier Analysis models, two techniques that can reduce the information asymmetry and improve the regulator’s skill to compare the performance of the utilities, a fundamental aspect in incentive r...

In this paper we introduce an influence measure based on second order expansion of the RV and GCD measures for the comparison between unperturbed and perturbed eigenvectors of a symmetric matrix estimator. Example estimators are considered to highlight how this measure compliments recent influence analysis. Importantly, we also show how a sample based version of this measure can be used to accu...

In multivariate statistical methods, it is important to identify influential observations for a reasonable interpretation of the data structure. In this paper, we propose a method for identifying influential data in the fuzzy C-means (FCM) algorithm. To investigate such data, we consider a perturbation of the data points and evaluate the effect of a perturbation. As a perturbation, we consider ...

Correlated or clustered data are frequently encountered in medical and dental research. Although there has been a large amount of research on analytic methods for clustered data, there has been only a limited amount of work in the area of influence diagnostics for these methods. We present a simple approach to influence diagnostics for clustered data that is practical even for very large data s...

We consider a model of opinion formation based on aggregation functions. Each player modifies his opinion by arbitrarily aggregating the current opinion of all players. A player is influential for another player if the opinion of the first one matters for the latter. A generalization of influential player to a coalition whose opinion matters for a player is called influential coalition. Influen...