切割點之估計

Abstract

切割點在建構使用基因影響表現分析的離群和或離群平均上扮演重要角色。我們在這篇論文中考慮了切割點的估計，其中樣本切割點估計量的近似分配，我們討論一種是根據經驗分位數來推導的，另一個是根據Chen和Chiang(1996)發展的對稱分位數來推導的。在檢測離群值的近似變異數和檢定力顯示由對稱分位數估計的樣本切割點跟經驗分位數比較起來是非常有競爭力的。

Cutoff point plays a vital role in constructing outlier sum or outlier mean which is used for gene influential expression analysis. We consider the estimation of the cutoff point in this paper. Asymptotic distributions of sample cutoff point estimates, one based on empirical quantiles and one based on symmetric quantiles of Chen and Chiang(1996), are developed. Comparisons of asymptotic variance and power for detecting outliers are performed showing that the version of sample cutoff point based on symmetric quantiles is very competitive with the one based on the empirical quantile.