Error rates of estimated Boolean functions using variable selection method when the error size is 0. The error rates were calculated from the three data sets with a different number of genes: 80, 100, and 120. The genes were randomly selected from the yeast cell cycle data set. (a) and (b) show the plots when the cutoff values are α1 = 1% and α1 = 2%, respectively. The appropriate values of α1 and α2 are 1% and 2% when the error size is 0.