between the first value and k value within the ߴ vector,
ݐୗൌmax
∀ቊ
∑
ሺݕെߤ௫ሻ
ୀଵ
߱
⁄
ߪణሺଵ:ሻ
ቋ
(6.14)
MOST p value is also calculated using the permutation approach.
OSS
sum of ordered subset square t statistic algorithm (LSOSS) is a
method proposed to calculate a t statistic based on MOST [Wang
ya, 2010]. The LSOSS t statistic is calculated in two steps. In the
, an optimal cutting point is sought by examining the best
n of a vector of the case expressions in terms of a standard
. The vector of the case expressions is sorted and then a cutting
varied between two and the length of the vector minus two. For
ential cutting point, two standard deviations are calculated. The
hese two standard deviations is believed to reach a maximum at
rying cutting points. Suppose the optimal cutting point is denoted
e optimal standard deviation sum at the optimal cutting point is
by ߪ௬∗. At this optimal cutting point, a LSOSS t statistic is
d using the following equation, where n and m are the lengths of
ors, namely x and y, respectively,
ݐୗୗୗൌ
݇∗൫ߤܡሺଵ:∗ሻെߤ௫൯
൫ߪ௫ߪ௬∗൯ሺ݊݉െ2ሻ
⁄
(6.15)
G
c assumption of the algorithm, which is named as discovering
ased on the tight Gaussian cluster (DOG), is that the majority of
ol expressions should have a small variance. Therefore, they form
tight Gaussian cluster [Yang and Yang, 2013]. It is assumed in