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Showing 32 of 32 methods
Bartlett's test
Equality of variances assuming normal data.
- Requires
- Numeric outcome, grouping column, normal residuals.
- Reports
- Chi-square, df, p.
- Source
- Bartlett, M. S. (1937). Proc. R. Soc. A, 160, 268–282.
Binary logistic regression
Model a binary outcome from one or more predictors.
- Requires
- Binary outcome and one or more numeric predictors.
- Reports
- Coefficients, SE, z, p, odds ratios with 95% CI, McFadden and Nagelkerke R², AIC, likelihood-ratio test, accuracy.
- Source
- Hosmer, D. W., Lemeshow, S. & Sturdivant, R. X. (2013). Applied Logistic Regression (3rd ed.). Wiley.
Chi-square goodness of fit
Compare observed category counts against expected proportions.
- Requires
- One categorical column.
- Reports
- Chi-square, df, p, expected counts.
- Source
- Pearson, K. (1900). Phil. Mag., 50, 157–175.
Chi-square test of independence
Test association between two categorical variables.
- Requires
- Two categorical columns; expected counts ≥ 5 preferred.
- Reports
- Chi-square, df, p, expected counts, Cramér's V, phi.
- Source
- Pearson, K. (1900). Phil. Mag., 50, 157–175.
Cochran's Q test
Compare three or more matched binary measurements.
- Requires
- Three or more paired binary columns.
- Reports
- Q, df, p.
- Source
- Cochran, W. G. (1950). Biometrika, 37, 256–266.
Cohen's kappa
Agreement between two raters on categorical judgements.
- Requires
- Two categorical columns with the same levels.
- Reports
- Kappa with 95% CI, observed and expected agreement.
- Source
- Cohen, J. (1960). Educational and Psychological Measurement, 20, 37–46.
Correlation matrix
All pairwise correlations across numeric variables with multiplicity control.
- Requires
- Three or more numeric columns.
- Reports
- Matrix of r, per-pair p, corrected p, heat map.
- Source
- Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences (2nd ed.). Erlbaum.
Cronbach's alpha
Internal consistency of a set of scale items.
- Requires
- Three or more numeric item columns measured on the same scale.
- Reports
- Alpha, number of items, total variance.
- Source
- Cronbach, L. J. (1951). Psychometrika, 16, 297–334.
Descriptive statistics
Summarise central tendency, dispersion and shape for every numeric variable.
- Requires
- At least one numeric column.
- Reports
- n, missing, mean, 95% CI, median, mode, SD, SE, variance, min/max, IQR, percentiles, skewness, kurtosis, outlier count.
- Source
- Tukey, J. W. (1977). Exploratory Data Analysis. Addison-Wesley.
Effect size estimation
Standardised magnitude of an observed difference or association.
- Requires
- Reported automatically alongside each inferential test.
- Reports
- Cohen's d, Hedges' g, dz, eta², omega², epsilon², Cramér's V, phi, rank-biserial r, odds ratio.
- Source
- Lakens, D. (2013). Frontiers in Psychology, 4, 863.
Fisher's exact test
Exact association test for 2×2 tables with small counts.
- Requires
- Two binary columns.
- Reports
- Exact p, odds ratio with 95% CI, risk ratio.
- Source
- Fisher, R. A. (1922). J. R. Statist. Soc., 85, 87–94.
Frequency tables
Count and proportion of each level for categorical variables.
- Requires
- At least one categorical column.
- Reports
- Counts, percentages, cumulative percentages, mode.
- Source
- Agresti, A. (2013). Categorical Data Analysis (3rd ed.). Wiley.
Independent-samples t-test
Compare means of two independent groups (pooled variance).
- Requires
- Numeric outcome, two-level grouping column, homogeneous variances.
- Reports
- t, df, p, mean difference, 95% CI, Hedges' g.
- Source
- Student (1908). Biometrika, 6, 1–25.
Jarque–Bera test
Normality test based on skewness and kurtosis; suited to larger samples.
- Requires
- Numeric column, n ≥ 30 recommended.
- Reports
- JB statistic, df, p.
- Source
- Jarque, C. M. & Bera, A. K. (1980). Economics Letters, 6, 255–259.
Kendall's tau-b
Rank concordance, preferred for small samples with many ties.
- Requires
- Two ordinal or numeric columns.
- Reports
- tau-b, z, p.
- Source
- Kendall, M. G. (1938). A new measure of rank correlation. Biometrika, 30, 81–93.
Kruskal–Wallis H test
Non-parametric comparison of three or more independent groups.
- Requires
- Numeric/ordinal outcome, grouping column with 3+ levels.
- Reports
- H (tie-corrected), df, p, epsilon², post-hoc pairwise Mann–Whitney with correction.
- Source
- Kruskal, W. H. & Wallis, W. A. (1952). JASA, 47, 583–621.
Levene's test (median-centred)
Test equality of variances across groups (Brown–Forsythe variant).
- Requires
- Numeric outcome and a grouping column with 2+ levels.
- Reports
- W, df1, df2, p.
- Source
- Brown, M. B. & Forsythe, A. B. (1974). JASA, 69, 364–367.
Linear regression (OLS)
Model a continuous outcome from one or more predictors.
- Requires
- Numeric outcome and one or more numeric predictors.
- Reports
- Coefficients with SE, t, p, 95% CI, R², adjusted R², F, RMSE, VIF, Durbin–Watson, residual plots.
- Source
- Draper, N. R. & Smith, H. (1998). Applied Regression Analysis (3rd ed.). Wiley.
Mann–Whitney U test
Compare distributions of two independent groups without normality.
- Requires
- Numeric or ordinal outcome, two-level grouping column.
- Reports
- U, z (tie-corrected), p, mean ranks, rank-biserial r.
- Source
- Mann, H. B. & Whitney, D. R. (1947). Ann. Math. Statist., 18, 50–60.
McNemar's test
Change in paired binary measurements.
- Requires
- Two paired binary columns.
- Reports
- Continuity-corrected chi-square, df, p, discordant pairs.
- Source
- McNemar, Q. (1947). Psychometrika, 12, 153–157.
Multiple testing correction
Control family-wise error or false discovery rate across a run.
- Requires
- Two or more p-values in the same analysis family.
- Reports
- Bonferroni, Holm–Bonferroni, and Benjamini–Hochberg adjusted p-values.
- Source
- Benjamini, Y. & Hochberg, Y. (1995). J. R. Statist. Soc. B, 57, 289–300.
One-sample t-test
Compare a sample mean with a reference value.
- Requires
- One numeric column.
- Reports
- t, df, p, mean difference, 95% CI, Cohen's d.
- Source
- Student (1908). The probable error of a mean. Biometrika, 6, 1–25.
One-way ANOVA
Compare means across three or more independent groups.
- Requires
- Numeric outcome, grouping column with 3+ levels, homogeneous variances.
- Reports
- F, df, p, sums of squares, eta², omega², post-hoc pairwise tests.
- Source
- Fisher, R. A. (1925). Statistical Methods for Research Workers. Oliver & Boyd.
Paired-samples t-test
Compare two repeated measurements on the same units.
- Requires
- Two numeric columns of equal length, paired row-wise.
- Reports
- t, df, p, mean difference, 95% CI, Cohen's dz.
- Source
- Student (1908). Biometrika, 6, 1–25.
Partial correlation
Association between two variables controlling for a third.
- Requires
- Three numeric columns.
- Reports
- Partial r, t, df, p.
- Source
- Fisher, R. A. (1924). The distribution of the partial correlation coefficient. Metron, 3, 329–332.
Pearson correlation
Linear association between two continuous variables.
- Requires
- Two numeric columns, approximately linear relationship.
- Reports
- r, 95% Fisher-z CI, t, df, p, r².
- Source
- Pearson, K. (1896). Mathematical contributions to the theory of evolution. Phil. Trans. R. Soc. A, 187, 253–318.
Shapiro–Wilk normality test
Test whether a sample plausibly comes from a normal distribution.
- Requires
- Numeric column, 3 ≤ n ≤ 5000.
- Reports
- W, p, Q–Q plot.
- Source
- Royston, P. (1995). Remark AS R94. Applied Statistics, 44, 547–551.
Sign test
Distribution-free test of median difference for paired data.
- Requires
- Two paired numeric columns.
- Reports
- Positive/negative counts, exact binomial p.
- Source
- Dixon, W. J. & Mood, A. M. (1946). JASA, 41, 557–566.
Spearman rank correlation
Monotonic association robust to outliers and non-normality.
- Requires
- Two numeric or ordinal columns.
- Reports
- rho, t, df, p.
- Source
- Spearman, C. (1904). The proof and measurement of association between two things. Am. J. Psychol., 15, 72–101.
Welch's ANOVA
Robust alternative to one-way ANOVA when variances differ.
- Requires
- Numeric outcome, grouping column with 3+ levels.
- Reports
- F*, df1, df2, p.
- Source
- Welch, B. L. (1951). Biometrika, 38, 330–336.
Welch's t-test
Two-group mean comparison without assuming equal variances.
- Requires
- Numeric outcome and a two-level grouping column.
- Reports
- t, Welch df, p, mean difference, 95% CI, Hedges' g.
- Source
- Welch, B. L. (1947). Biometrika, 34, 28–35.
Wilcoxon signed-rank test
Non-parametric comparison of two paired measurements.
- Requires
- Two paired numeric columns.
- Reports
- W, z, p, rank-biserial r.
- Source
- Wilcoxon, F. (1945). Biometrics Bulletin, 1, 80–83.
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