A Scatterplot of the negative log10-transformed p-Values derived from a specific t-test against the log2-fold change in expression. Genes whose expression is decreased lie to the left of the Mean; genes whose expression is increased lie to the right of the mean. Genes with statistically significant differential expression lie above a horizontal threshold. This plot provides an effective means for visualizing the direction, magnitude, and significance of changes in gene expression. SeeVolcano Plot.