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|Table of Contents Statistical Tests Outlier Tests Walsh's Outlier Test|
|See also: Outlier Test - Dean and Dixon|
Let X1, X2, ... , Xn represent the data ordered from smallest to largest. If n<60, do not apply this test. If 60<n<=220, then a = 0.10. If n >220 then a = 0.05.
|Step 1:||Identify the number of possible outliers, r >= 1.|
where ceil() indicates rounding the value to the largest possible integer (i.e., 3.21 becomes 4).
|Step 3:||The r smallest points are outliers (with a a% level of significance) if Xr - (1+a)Xr+1 + aXk < 0|
|Step 4:||The r largest points are outliers (with a a% level of significance) if Xn+1-r - (1+a)Xn-r + aXn+1-k > 0|
|Step 5:||If both of the inequalities are true, then both small and large outliers are indicated.|
Last Update: 2005-Mai-08