Natural Resource Biometrics

F distributions

Figure 1. Example of an F distribution illustrating the critical value for an a = 0.05, v1 = 10, v2 = 10.

For table of F critical values at the a = 0.05 level.

In Excel® to look up a table number use:

=F.INV.RT(probability, degrees of freedom 1, degrees of freedom 2)

Example:

=F.INV.RT( 0.05, 29, 29 )

Which will produce:

1.860811

Also See:

Chapter 9 - Significance of a Difference between Two Means pages 108-124 in:

Phillips, J. L. 2000. How to think about statistics. W. H. Freeman and Co. New York. 202 pp. ISBN 0-7167-3654-3

Chapter 9 - Two-Sample Hypotheses pages 126-130 in:

Zar, J. H. 2007. Biostatistical Analysis. Prentice-Hall, Inc. Englewood Cliffs, New Jersey. 718 pp.