Analysis of proportions using approximate and exact methods
Key Words and Terms:
Analysis, analysis of 2 proportions
Analysis, binary data analysis
Analysis, categorical data analysis
Analysis, discrete data analysis
Chi-square, Pearson chi-square statistic of association
Table , contingency table
Inference on discrete data uses an approximate method (the chi-square) used for large samples and one exact method
(Fisher's Exact Method) used for small samples.
Approximate methods are accurate for large samples and are inaccurate for small samples.
The data is laid out in contingency tables and is inspected manually before application of statistical tests.
The Pearson chi
square is computed easily by most computer statistical programs. The computer also gives the p-value corresponding to the
chi-square. Statisticians interpret the p-value to decide whether there is a statistically significant difference or a significant
association between 2 groups being compared.