t distributions

[Image]
Figure 1. Example of an t distribution illustrating the critical value for an α = 0.05, df = 30, 2-tailed.
[Image]
Figure 2. Example of an t distribution illustrating the critical value for an α = 0.05, df = 30, 1-tailed.

For table of t critical values .

In Excel® to look up a table number use:

=T.INV.2T(probability, degrees of freedom)

Example:
=T.INV.2T( 0.05, 29 )
Which will produce:
2.04523


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.


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Natural Resources Biometrics by David R. Larsen is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License .

Author: Dr. David R. Larsen
Created: July 19, 2000
Last Updated: September 24, 2014