Improved Estimators of the Hazard Rate from a Selected Gamma Population Under an Asymmetric Loss

Kanaka Lata Ojha1
1SOA: Siksha O Anusandhan University, Bhubaneswar, India

Tóm tắt

We consider the problem of estimation of the hazard rate from a selected gamma population. Let $$\Pi _{1}$$ , $$\Pi _{2}$$ be two populations, where $$\Pi _{i}$$ follows an one parameter gamma distribution with hazard rate $$\lambda _{i}$$ , $$i=1,2$$ . Let $$ X_{i1},X_{i2},\ldots ,X_{in}$$ be an independent random sample drawn from the population $$\Pi _{i}$$ , $$i=1,2$$ . Consider $$ X_{i}={\sum _{j=1}}^{n}X_{ij} $$ to be the sample mean of the ith population The natural selection rule is to select the population with largest(smallest) mean. That is $$\Pi _{i}$$ if $$X_{i}=max(min)(X_{1},X_{2})$$ . Some natural estimator are proposed and it was shown that they are admissible within a class of estimators with respect to the entropy loss. Further some improved estimators are obtained which improves upon the natural estimators.

Tài liệu tham khảo

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