## Determining Significance Level

for an F-Test

## If you have examined the F-distribution table, you will have noticed that values for two-tailed tests aren't given. To find the rejection regions for a two-tailed test, the procedure is simple:

- Determine the Significance level .

- Divide that value in half (one-half for each side of the distribution).

- For the right side, simply look up the value in the table, keeping in mind that your significance level is one-half the original.

- For the left side, reverse the values for the numerator and denominator: from n
_{1 }/n_{2}to n_{2}/n_{1}. Look up these values on the table, at one-half the significance level, and take the reciprocal of that number. This number is the left-side critical value.

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