- **Correlation & regression** — Pearson r, R², Spearman ρ (with tie handling), least-squares line, standard errors, t and p for the slope, prediction, scatter plot.
- **Hypothesis tests** — one-sample, two-sample (Welch / Student), paired t-tests with CI and Cohen d; one-way ANOVA with η²; chi-square test of independence with Cramér V and expected-frequency warning.
- **Distributions** — Normal, Student t, χ², F, Binomial, Poisson: density/PMF, CDF, tail, quantiles, chart with shaded P(X ≤ x).
- Saved data sets (SQLite), share results as text, example data on every screen.
- UI languages: English (default), Bulgarian, German, French, Spanish — switchable inside the app (AppCompat per-app locales).
## Build
Android Studio Hedgehog 2023.1.1 · AGP 8.2.2 · Gradle 8.2 · compileSdk 34 · minSdk 24 · JDK 17.
## Data input
Numbers separated by spaces, new lines, tabs or `;`. A comma is a decimal separator when other separators are present (`1,5 2,7`), otherwise it separates values (`1,2,3`).
What does the app contain:
Descriptive statistics – mean, median, mode, variance and standard deviation (for a sample and for the general population), standard error, coefficient of variation, confidence interval, quartiles, skewness, kurtosis, geometric and harmonic mean, outliers. There is a histogram with a normal curve and a box plot.
Correlation and regression – Pearson and Spearman coefficients, R², regression line with p-value, prediction and scatter plot.
Hypothesis testing – t-tests (one-sample, two-sample Welch or Student, paired samples), ANOVA and χ² test for independence. Results include effect size and conclusion on whether H₀ is rejected.
Distributions – normal, t, χ², F, binomial and Poisson. Calculates probabilities and quantiles and displays a shaded area plot.
Features – saving data in SQLite, sharing results as text, and an "Example" button on each screen.
Languages – EN (default), BG, DE, FR, ES. Switchable from the “Language” button in the application itself, regardless of the device language.