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. 2016 Mar 13;2016:2615348. doi: 10.1155/2016/2615348

Table 6.

Simulation results for selecting k important variables among 2,000 candidates including the most and least important surrogate variables across 600 subjects.

Bonferroni FDR TT
n.sv = 5 n.sv = 10 n.sv = 15 n.sv = 5 n.sv = 10 n.sv = 15 n.sv = 5 n.sv = 10 n.sv = 15
Most important surrogate variables included

# incorrect
k = 10 0 0 0 6 6 6 5 4 3
k = 100 2 3 2 19 19 19 7 5 5
k = 200 6 6 5 26 29 29 6 6 4
k = 400 12 11 11 40 38 39 7 7 7

Sensitivity
k = 10 1 1 1 1 1 1 1 1 1
k = 100 0.98 0.97 0.98 1 1 1 0.98 0.98 0.98
k = 200 0.97 0.97 0.975 0.995 0.995 0.995 0.985 0.985 0.985
k = 400 0.97 0.973 0.973 1 1 1 0.988 0.988 0.985

Specificity
k = 10 1 1 1 0.997 0.997 0.997 0.997 0.998 0.998
k = 100 1 1 1 0.99 0.99 0.99 0.997 0.998 0.998
k = 200 1 1 1 0.986 0.984 0.984 0.998 0.998 0.999
k = 400 1 1 1 0.975 0.976 0.976 0.999 0.999 0.999

Most important surrogate variables not included

# incorrect
k = 10 10 10 10 10 10 10 10 10 10
k = 100 100 100 100 100 100 100 100 100 100
k = 200 200 200 200 200 200 200 200 200 200
k = 400 400 400 400 400 400 400 400 400 400

Sensitivity
k = 10 0 0 0 0 0 0 0 0 0
k = 100 0 0 0 0 0 0 0 0 0
k = 200 0 0 0 0 0 0 0 0 0
k = 400 0 0 0 0 0 0 0 0 0

Specificity
k = 10 1 1 1 1 1 1 1 1 1
k = 100 1 1 1 1 1 1 1 1 1
k = 200 1 1 1 1 1 1 1 1 1
k = 400 1 1 1 1 1 1 1 1 1

FDR: false discovery rate, TT: training and testing, n.sv = number of surrogate variables, and k: the number of truly important CpG sites out of 2,000.