Mathematics
Applied statistics
Description, estimation, comparison and statistical models.
- Binomial and Poisson distributionsP(X = k), P(X ≤ k) and P(X ≥ k) for the binomial and Poisson distributions, computed in log space, tails summed from the right side.
- Chi-square test, goodness of fit and independenceχ² statistic, degrees of freedom, p-value and critical value, with cell-by-cell detail and Cochran’s rule checked.
- Confidence interval calculatorCI for a mean (Student or normal) and for a proportion using the wilson interval, more reliable than Wald, shown alongside for comparison.
- Correlation and linear regressionLeast-squares line, r and r², slope p-value, confidence and prediction intervals, residuals point by point.
- Descriptive statistics, mean, median, standard deviationCalculate mean, median, range, variance and standard deviation of a series of values, with the sample / population distinction.
- Normal distribution calculatorProbabilities, z-scores and critical values of the normal distribution (P(X ≤ x), P(a ≤ X ≤ b), quantiles) at machine precision, tails included.
- One-way ANOVA, comparing multiple meansCompare means across multiple groups with the complete ANOVA table: sum of squares, F-statistic, p-value, and cautious conclusion.
- Student's t-test, comparison of meansCompare a mean to a reference value or two independent samples (Welch's t-test): t, degrees of freedom, p-value, confidence interval and conclusion.