Help & Documentation

Guides for every Statulator tool: formulas, worked examples, interpretation, and references.

Sample Size: Proportions

Estimating a Single Proportion

Sample size for prevalence surveys and proportion estimation with precision-based design.

Comparing Two Independent Proportions

Power-based design for RCTs and cohort studies comparing binary outcomes between two groups.

Comparing Paired Proportions

McNemar’s test design for before-after studies and diagnostic test comparisons on paired binary data.

Sample Size: Means

Estimating a Single Mean

Precision-based design for surveys estimating a population mean with a confidence interval.

Comparing Two Independent Means

Power-based design for two-arm trials comparing group means, with equality, non-inferiority, and equivalence options.

Comparing Paired Differences

Paired t-test design for before-after, crossover, and matched-pairs studies.

Dataset Analysis, Statistical Testing, and Data Visualization

Univariate Analysis

Summary statistics, histograms, Q-Q plots, box plots, frequency tables, bar charts, and pie charts for individual variables.

Bivariate Analysis

Scatter plots, grouped box plots, and contingency tables for exploring relationships between variable pairs.

Stat Analysis

Interactive pairwise association matrix with correlation, chi-square, t-tests, ANOVA, and non-parametric tests on demand.

StatPlot

27 publication-quality chart types with customisable themes, palettes, titles, axis controls, and PNG export.

Statistical Tests: Confidence Intervals

CI for a Single Proportion

Wald, Wilson Score, and Exact (Clopper-Pearson) intervals for a binomial proportion.

CI for a Single Mean

Confidence interval using t or z distribution for a population mean from sample data.

Statistical Tests: Chi-square & Association

Chi-square Test

Test of independence for 2×2 tables with odds ratio, relative risk, and Yates correction.

Chi-square Goodness-of-fit

Compare observed categorical frequencies to expected proportions with post-hoc z-tests.

Stratified Analysis

Mantel-Haenszel pooled estimates, Breslow-Day homogeneity test, and confounding assessment.

Statistical Tests: t-Tests

One-Sample t-Test

Test whether a sample mean differs from a hypothesised reference value.

Independent Two-Sample t-Test

Compare means of two independent groups with pooled or Welch’s variant.

Paired t-Test

Test whether the mean difference between paired observations (before/after) differs from zero.

Each help page includes an overview, a worked example with step-by-step Statulator instructions, an interpretation guide, detailed formulas, assumptions, and academic references. Use the icon on any calculator page to jump directly to its help page.