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.

Library references