Target: Check if the statistical model fits the observations. The test uses Chi-square distribution
Example: checking a fair dice.
Model: the probability of each side is equal - 1/6
H0: fair dice
H1: unfair dice
The groups are the dice's numbers (1,2,3,4,5,6)
In this example, you throw the dice n times
Expected frequency for each group is n/6
Observed frequency, the actual times each number appears
H_{0}: Model Fits | |
H_{1}: Model Doesn't Fit | |
Degree Of Freedom (DF) = n - m - 1
Group | Observed Frequency |
Expected Frequency |
---|---|---|
The total of the Expected Frequency must be equal to the total of the Observed Frequency
You may copy data from Excel, Google sheets or any tool that separate data with Tab and Line Feed.
Copy the data, one block of 3 consecutive columns includes the top header row and left header column, and paste below.
hover for example
k: | number of groups | |
n: | sample size | |
χ² | Chi square test statistic |