A relevant metric of such expression difference is the fold change (FC), calculated as FC = Expression(Brain)/Expression(Reference).
If the JS metric of the expression levels of two uncertain segments is low (which means both segments are positively correlated), then both segments are likely to be included on the same isoform (termed "coexpressed segments", see Figure 1(B) for an example).
To ensure that the extent of variability indeed parallels the objective extent of mechanistic participation, the variability data were aligned with differential expression consistency and metric of tissue-specific expression.
In addition, using Local Network Similarity (LNS), a recently proposed metric for expression divergence, we assessed the expression conservation of between-species pairs of orthologs, and within-species gene-protein expression profiles.
Recently, a metric for expression divergence called Local Network Similarity LNSS) was proposed to assess expression conservation of a pair of orthologs [ 20].
Using Pearson's correlation coefficient (r) as a metric of similarity between expression values, correlation matrices were first calculated.
The t-test provides a useful metric of differential tissue expression, although the formal requirements for the underlying distribution of the data may not be completely met [ 20].
These findings are mirrored in the results shown in Figure 2, and were captured by the metric of shared differential expression across multiple experiments.
For instance, the predominant metric of differential gene expression is silent on disease relevance of identified gene products, since it provides no measure of their functional relatedness [ 38], and its resulting signatures do not replicate well across datasets [ 7, 39].
This distance metric scales the measurement of expression conservation between −1 and 1, with the null-hypothesis distribution centered at zero.
