ANOVA / ANCOVA
- Balanced and unbalanced designs
- Missing cells
- Factorial, nested, Latin square, and mixed designs
- Repeated measures
- Box, Greenhouse–Geisser, and Huynh–Feldt corrections
Video – Two-way ANOVA in Stata
Video – Analysis of covariance in Stata
EFFECT SIZES
- Eta-squared—η2
- Epsilon-squared—ε2
- Omega-squared—ω2
- Confidence intervals
POSTESTIMATION AFTER ANOVA
- Tests for effects, including pooling and nonresidual error terms
- Tests for expressions involving the coefficients of the underlying regression model
- Bonferroni, Holm, and Šidák adjustments for multiple tests
- Ability to display symbolic forms
- Predictions and influence statistics
- Expected values
- Residuals, standardized residuals, studentized residuals
- Standard error of the prediction or residuals
- Leverage
- Cook’s D
- COVRATIO
- DFBETAs
- Diagonal of hat matrix
- Welsch distance
- Diagnostic plots
- Residual versus fitted
- Added-variable plot
- Component plus residual
- Augmented component plus residual
- Residual versus predictor
- Leverage versus squared residual
MANOVA
- Multivariate test statistics
- Wilks’ lambda
- Pillai’s trace
- Lawley–Hotelling trace
- Roy’s largest root
- Balanced and unbalanced designs
- Missing cells
- Factorial, nested, Latin square, and mixed designs
- Repeated measures
POSTESTIMATION AFTER MANOVA
- Multivariate tests (Wilks’ lambda, Pillai’s trace, etc.) for
- Terms from the model
- Pooled terms
- Terms (or pooled terms) tested using other terms (or pooled terms) as the error term
- Linear combinations of the underlying design matrix
- Wald tests of expressions involving the coefficients of the underlying regression model
- Predictions
- Point estimates
- Standard error of point estimates
- Residuals
- Combinations of estimators
- Linear and nonlinear
- Confidence intervals
POSTESTIMATION SELECTOR
- View and run all postestimation features for your command
- Automatically updated as estimation commands are run
FACTOR VARIABLES
- Automatically create indicators based on categorical variables
- Form interactions among discrete and continuous variables
- Include polynomial terms
- Perform contrasts of categories/levels
MARGINAL ANALYSIS
- Estimated marginal means
- Marginal and partial effects
- Average marginal and partial effects
- Least-squares means
- Predictive margins
- Adjusted predictions, means, and effects
- Works with multiple outcomes simultaneously
- Contrasts of margins
- Pairwise comparisons of margins
- Profile plots
- Interaction plots
- Graphs of margins and marginal effects
- A single categorical variable
- A single continuous variable
- Interactions of categorical variables
- Interactions of categorical and continuous variables
- Interactions of two continuous variables
CONTRASTS
- Analysis of main effects, simple effects, interaction effects, partial interaction effects, and nested effects
- Comparisons against reference groups, of adjacent levels, or against the grand mean
- Orthogonal polynomials
- Helmert contrasts
- Custom contrasts
- ANOVA-style tests
- Contrasts of nonlinear responses
- Multiple-comparison adjustments
- Balanced and unbalanced data
- Contrasts of means, intercepts, and slopes
- Graphs of contrasts
PAIRWISE COMPARISONS
- Compare estimated means, intercepts, and slopes
- Compare marginal means, intercepts, and slopes
- Balanced and unbalanced data
- Nonlinear responses
- Multiple-comparison adjustments: Bonferroni, Šidák, Scheffé, Tukey HSD, Duncan, and Student–Newman–Keuls adjustments
- Group comparisons that are significant
- Graphs of pairwise comparisons