1.1 Problem Statement

"What problem are you trying to solve?" -- Lazar Arulnayagam

When comparing biological effects on genes in two experiments, two important questions arise:

1. Are the genes shared? (Venn)
2. Are the changes concordant in direction? (Venndir)

A Venn diagram does not include direction, and cannot answer question 2.

Venndir proposes a simple extension to a Venn diagram, the placement of signed counts beside the main counts. The signed counts summarize the directionality of the main counts, and are described using directional arrows, up and down, and are reinforced using color, red for up, and blue for down.

Figure 1.2: Venndir introduces an extension to a Venn diagram, with addition of directional counts beside each Venn overlap count. The direction is indicated by arrows up and down, and colors red and blue, respectively.