What column order do you expect for pasted or CSV data?

Each row should contain x, y, and optionally w (weight). Rows lacking w assume w = 1. The tool auto-detects delimiters and decimal marks, strips thousands separators, and logs how many invalid tokens were removed.

When should I switch to the Theil–Sen estimator?

Use Theil–Sen when outliers or leverage points distort OLS. We compute the median slope/intercept, plot the fit with bands, and provide the same diagnostics so you can compare against OLS or WLS.

Linear Regression & Correlation — Scatter, OLS/WLS, R² (with steps)

Input & options

Data (one row per x,y[,w])

CSV file

Decimal separator Delimiter

Estimator Intercept

95% confidence band 95% prediction band

Summary

Run the calculation to see metrics and the step log.

Metric	Value

How it’s calculated

Visualisation

Scatter plot, regression line, and 95% bands

Residuals vs fitted values to spot patterns and leverage

Teacher notes

Compare OLS, WLS, and Theil–Sen with or without an intercept to highlight how slope and tests respond to weighting or outliers.
The step log records means, sums, coefficients, r/R², residual diagnostics, tests, ANOVA, and the LaTeX formula so students can follow each computation.
The exported CSV includes x, y, w, fitted values, residuals, leverage, and Cook’s D for further analysis in spreadsheets.

FAQ

How is Weighted Least Squares implemented?

We recompute weighted means and covariances using w, derive the fitted line, and propagate weights to residual sums and Cook’s distance so diagnostics reflect the weighting scheme.

What does the shareable URL include?

The URL stores decimal, delimiter, estimator, intercept, and band options. Data is not embedded, so share the dataset separately when collaborating.

Input & options

Summary

How it’s calculated

Visualisation

Teacher notes

FAQ

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