20131003 多變量分析

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1. 隨著n增加，抽樣分配會更趨近於鐘形的常態機率分配à中央極限定理

＊- normality of the metric variables
＊- homoscedastic relationships between variables
＊- linear relationships between variables

＊- absence of correlated prediction errors

Transforming是試誤法