16.5: Critical Values of Chi-Square (Chi-Square Table)
- Page ID
- 57473
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Illustrated in Figure \(\PageIndex{1}\), the value of the chi-square that cuts off a right tail of area \(c\) is denoted \(\chi_c^2\) and is called a critical value.
Degrees of Freedom
Like with the t-test and ANOVA, the degrees of freedom are based on the kind of analysis you are conducting.
- \(\chi_{GoF}^2\) Goodness of Fit: \(C-1\)
- C is the number of columns
- \(\chi_{ToI}^2\) Test of Independence: \((R-1)\times(C-1) \)
- R is the number of rows
- C is the number of columns
Table of Critical Values for \(\chi_c^2\)
Table \(\PageIndex{1}\) below gives values of \(\chi_c^2\) for various values of \(c\) and under several chi-square distributions with various degrees of freedom.
| df | p = 0.10 | p = 0.05 | p = 0.01 |
|---|---|---|---|
| 1 | 2.706 | 3.841 | 6.635 |
| 2 | 4.605 | 5.991 | 9.210 |
| 3 | 6.251 | 7.815 | 11.345 |
| 4 | 7.779 | 9.488 | 13.277 |
| 5 | 9.236 | 11.070 | 15.086 |
| 6 | 10.645 | 12.592 | 16.812 |
| 7 | 12.017 | 14.067 | 18.475 |
| 8 | 13.362 | 15.507 | 20.090 |
| 9 | 14.684 | 16.919 | 21.666 |
| 10 | 15.987 | 18.307 | 23.209 |
| 11 | 17.275 | 19.675 | 24.725 |
| 12 | 18.549 | 21.026 | 26.217 |
| 13 | 19.812 | 22.362 | 27.688 |
| 14 | 21.064 | 23.685 | 29.141 |
| 15 | 22.307 | 24.996 | 30.578 |
| 16 | 23.542 | 26.296 | 32.000 |
| 17 | 24.769 | 27.587 | 33.409 |
| 18 | 25.989 | 28.869 | 34.805 |
| 19 | 27.204 | 30.144 | 36.191 |
| 20 | 28.412 | 31.410 | 37.566 |
| 100 | 118.498 | 124.342 | 135.807 |


