First, use the Critical Significance Level (α: alpha)
chosen in Step 2 and degrees of freedom (df)
calculated in Step 3 (where df = one less than the number of rows multiplied by one less than the number of columns in the contiguency table) to find the Critical Value
of Χ2 (Χ2critical) using a Critical Value Table such as the one below e.g., if α = 0.05 and df = 3, then Χ2critical = 7.8.
Second, compare Χ2critical with the value for the Χ2 statistic calculated in Step 3.
Reject your Null Hypothesis
if your calculated value is greater than or equal to the critical value; Χ2 ≥ Χ2critical (significant result).
Accept your Null Hypothesis
if your calculated value is less than the critical value; Χ2 < Χ2critical (non-significant result).
E.g., if Χ2 = 9.62 and Χ2critical = 7.8 then reject the Null Hypothesis.
| degrees of freedom | α = 0.9 | α = 0.5 | α = 0.1 | α = 0.05 | α = 0.01 |
|---|---|---|---|---|---|
| 1 | 0.016 | 0.455 | 2.706 | 3.841 | 6.635 |
| 2 | 0.211 | 1.386 | 4.605 | 5.991 | 9.210 |
| 3 | 0.584 | 2.366 | 6.251 | 7.815 | 11.345 |
| 4 | 1.064 | 3.357 | 7.779 | 9.488 | 13.277 |
| 5 | 1.610 | 4.351 | 9.263 | 11.070 | 15.086 |
| 6 | 2.204 | 5.348 | 10.645 | 12.592 | 16.812 |
| 7 | 2.833 | 6.346 | 12.017 | 14.067 | 18.475 |
| 8 | 3.490 | 7.344 | 13.362 | 15.507 | 20.090 |