How to Use the F-Distribution Calculator

Introduction

Instructions

1. Degrees of Freedom (Numerator): Enter the degrees of freedom associated with the numerator (usually the number of groups minus 1 in an ANOVA test).
2. Degrees of Freedom (Denominator): Enter the degrees of freedom associated with the denominator (usually the total number of observations minus the number of groups in an ANOVA test).
3. Alpha Value: Enter the significance level for the test. Depending on the confidence level you are interested in.
4. Calculate: Click the “Calculate” button to obtain the critical F-value.

Examples

Example 1

• Scenario: You are performing an ANOVA test with 3 groups and 15 observations in total.
• Degrees of Freedom (Numerator): $3-1=2$$3-1=2$3-1=23 – 1 = 2$3-1=2$
• Degrees of Freedom (Denominator): $15-3=12$$15-3=12$15-3=1215 – 3 = 12$15-3=12$
• Alpha Value: $0.05$$0.05$0.050.05$0.05$

Example 2

• Scenario: You are conducting a regression analysis with 4 predictors and 20 observations.
• Degrees of Freedom (Numerator): $4$$4$44$4$ (number of predictors)
• Degrees of Freedom (Denominator): $20-4-1=15$$20-4-1=15$20-4-1=1520 – 4 – 1 = 15$20-4-1=15$
• Alpha Value: $0.01$$0.01$0.010.01$0.01$