Tests of Significance Statistical tests allow biologists to estimate the probability that any differences between their experimental results and the predictions of the null hypothesis are due to chance alone. This probability is abbreviated as P. Usually, biologists accept a level of uncertainty of 5% or less (P < 0.05). A P = 0.05 means that at most (estimated) a 5% chance that you will be wrong if you reject the null hypothesis. A difference between the observed results and those predicted under the null hypothesis that is large enough to produce such a small P value is termed a significant difference.

 

How to calculate a t-test	How to calculate a Chi-square	How to calculate a G-test	(t-test critical values)
T-test tutorial	Chi-square tutorial		(G-test critical values)

 

 

 

 

 

 

 

 

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