### Description

This column shows the similarity of the expression of each gene to the selected gene. Genes with identical expression profiles show a value of zero. This column shows data only for the 1000 genes (including splicing variants) that have the most similar expression profiles.

### Methods

The expression distance between two genes is a weighted sum computed with the following formula:

         delta(a,b) = sum(w[i] * |a[i] - b[i]| ) / sum(w[i])

where a and b are expression vectors associated with the two genes indexed by tissue, w is an array of weights, and the sums are taken over all tissues. When there are multiple replicates for a tissue, the median value is used. A weight of 0.1 is used for the cancer cell lines. Tissues derived from the brain and nervous system are weighted 0.5 because they are overrepresented. Within the set of ovary-derived tissues, a weight of 0.5 is used for the tissue labeled "ovary" and 0.25 is used for tissues labeled "OVR278E" and "OVR278S". All other tissues are weighted 1.0.