The phrase "average expression value" is correct and usable in written English.
It can be used in contexts such as data analysis, statistics, or scientific research when discussing the mean value of a set of expression data.
Example: "The average expression value of the gene was calculated to determine its overall activity in the sample."
Alternatives: "mean expression level" or "typical expression value".
The relative expression levels of each probe for all the stimulation sets, compared with the control, were determined based on the average expression value of each probe; probes differentially expressed by greater than 4.0-fold were selected.
Subsequently, we compared all possible combinations of average expression value at each time point, and selected expressed targets with more than two-fold differences in at least one pairwise comparison from cycling genes.
Of those 41 probesets, only 7 were expressed (17% (7/41) when compared to the 28% of the 54,000 probesets across the entire genome that were expressed) in the lymphoblastoid cell lines, with an average expression value above "100" using GCRMA normalization data (Additional file 1 Table S1).
Interestingly, we observed a 2-fold increase in GPNMB/OA mRNA levels in the epithelium of breast tumors characterized as high MVD (average expression value = 1.452) versus those with low MVD (average expression value = 0.734) (Figure 3B).
For a given probe in a time course series, the average expression value across the three zeros was subtracted from every expression value in that series.
Briefly, the expression of the genes of interest was calculated in relative copy numbers (RCN), which is relative to the average expression value of two housekeeping genes.
The normalized data were further converted into log2 ratios of expression values over the average expression value across all the samples for each probe.
The average expression value of genes located in one same operon was adopted to characterize the expression level of the operon.
According to the common definition, both operons and genes not assigned to any operons, were regarded as transcript units, and the average expression value of within-operon genes was adopted to characterize the expression profile of the operon.
An average expression value for each time point (0 and 24 hours) was obtained by averaging the median normalized gene-level expression value for the two replicate per time point.
For gene expression comparisons, genes with an average expression value less than 100 for both comparison groups for Affymetrix data or detection p-values >0.01 from BeadStudio for Illumina data, or fold-change less than 1.2 fold (up or down-regulated), were excluded from further statistical analyses.
