ChiSquare
ChiSquare Table
Tool based on hypotheses
testing that incorporates a table of calculated probabilities,
(i.e., tail areas under a bell shaped curve), based on a normal distribution
using the probability and degrees of freedom. Table is used to pinpoint an
expected probability for the preferred confidence level for determining or
comparing groups of test data.
The hypotheses is the standard
deviation, (sigma), of a normal population is equal to a
specific value of a standard or reference sigma value; center line.
The formula with degrees of freedom is ...


(n
 1)s^{2} 
X^{2} 
= 



S_{0}^{2} 
For additional information, see the
National Institute of Standards and Technology's page titled Critical
Values of the ChiSquare Distribution.