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Chi-Square Goodness of Fit Test
Formula
The goodness-of-fit test determines whether observed data follows an expected distribution. For example, testing whether a die is fair by comparing observed roll frequencies to the expected uniform distribution.
If the chi-square statistic exceeds the critical value, the data does not fit the expected distribution at the chosen significance level.
Common use cases:
- Testing if a die or coin is fair
- Verifying distribution assumptions
- Market research category analysis
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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