Chi-Square Independence (2x2)

All statistics tools

Determine if there is a significant relationship between two categorical variables.

Contingency Table (2x2)

Category A

Group 1

Group 2

Category B

Group 1

Group 2

Statistical Analysis

Chi-Square Stat (χ²)11.6667

Significance ResultStatistically Significantat 95% Confidence (α=0.05)

P-Value0.000636

About this calculator

Overview

The Chi-Square test of independence (2x2) is used to determine if two categorical variables are related. It compares the observed frequencies in a contingency table to the expected frequencies that would be predicted if the variables were completely independent of each other.

💡

Pro Tips

Ensure your data represents counts (frequencies), not percentages or measurements like height or weight.
A p-value below 0.05 typically indicates that the relationship between variables is 'statistically significant'.
For 2x2 tables, the Degrees of Freedom (df) is always 1.

Fun Facts

"Waiters and waiters use Chi-Square tests to see if things like drawing a smiley face on a receipt significantly increases tips!"
"A/B testers use Chi-Square to prove that a specific website change actually improved conversion rates, rather than it just being random noise."
"The test assumes that each 'cell' in your table has an expected frequency of at least 5 for the results to be reliable."

Formula: χ² = Σ [ (Oᵢ - Eᵢ)² / Eᵢ ]