**A simple correlation testing technique.**
**Fourfold Contingency Table** - basically a [[Scatter Chart]] presented as a [[Quadrant Charts|Matrix Diagram]].
A test to see if two distinct variables are linked.
```mermaid
%%{init: {"quadrantChart": {"chartWidth": 400, "chartHeight": 400}}}%%
quadrantChart
x-axis Not A --> A
y-axis Not B --> B
quadrant-1 B & A
quadrant-2 B NOT A
quadrant-3 NOT B NOT A
quadrant-4 A NOT B
result 1: [0.8, 0.3]
result 2: [0.9, 0.2]
result 3: [0.55, 0.25]
result 4: [0.3, 0.33]
result 5: [0.87, 0.15]
result 6: [0.97, 0.55]
```
This is related to the Chi-squared test.
****
# More
## Source
- [[The Organized Mind]]
## Related
- [[Base Rates]]