On upper bounds for the variance of functions of random variables with weighted distributions

Resumo

Cacoullos and Papathanasiou (1989) obtained a characterization for the distribution of a random variable via the upper bounds for the variance of a given function of that random variable. In this paper, on the basis of their works, we derive a characterization for the weighted distribution. Subsequently, by using the characterization and in terms of Chernoff-type inequalities, we find the upper bounds for the variance of a given function of the weighted random variable. Moreover, assuming that X is IFR [increasing failure rate] we compute an upper bound for the variance of this function.