From: Statistical methods for constructing disease comorbidity networks from longitudinal inpatient data
 | Second disease is j | Second disease is not j | Total |
---|---|---|---|
First disease is i | a=wij/S | \(b=s_{i}^{\text {out}}/S -w_{ij}/S\) | \(a+b=s_{i}^{\text {out}}/S \) |
First disease is not i | \(c=s_{j}^{\text {in}}/S-w_{ij}/S \) | \(d=1-s_{i}^{\text {out}}/S -s_{j}^{\text {in}}/S + w_{ij}/S\) | \(c+d=1-s_{i}^{\text {out}} /S\) |
Total | \(a+c=s_{j}^{\text {in}}/S \) | \(b+d=1 -s_{j}^{\text {in}}/S \) | 1 |