One proportion z-test
Hypothesis tests · Method and input reference
Two-sided tests; z-test uses null variance (pooled for two groups). Binomial test is exact.
Open calculator · Compare methods in the decision matrix
When to consider it
- Compare a proportion against a reference using the large-sample z approximation.
Assumptions and scope
- Observations must be independent between subjects; repeated rows from one subject are not independent samples.
- Normal approximation requires adequate expected success/failure counts. Use the exact binomial or Fisher branch when appropriate.
Required inputs
- Successes — Enter the method parameter described above.
- Trials — Enter the method parameter described above.
- Null proportion — Enter the method parameter described above.
Review missing values and data coding before running. Sample inputs are synthetic teaching examples.
Implementation
Lifescio validates inputs and formats results; listed functions are the principal calculation routines, not an exhaustive transitive dependency list.
- statsmodels 0.14.4: statsmodels.stats.proportion.proportions_ztest
These are pinned library versions; saved results record the versions actually used at runtime.