stat-contour-filled - Filled iso-band statistic. Partitions the (x, y, z) field into bands defined by successive levels and emits one closed polygon per cell that touches each band. Pair with geom-polygon or geom-contour-filled.
stat-ecdf - ECDF statistic: one row per unique x value with the cumulative fraction.
stat-ellipse - Covariance-ellipse statistic: one ellipse per group from the sample covariance of (x, y).
stat-qq - Q-Q statistic: theoretical-vs-sample pairs against a reference distribution.
stat-qq-line - Q-Q reference-line statistic: two endpoints of the IQR-fitted line.
Functions and helpers
stat-align - Align statistic: resample each group onto a shared x-grid.
stat-connect - Connection statistic: expand consecutive points with intermediate vertices.
stat-function - Sample fun at n points across xlim and emit (x, y) rows.
stat-identity - Identity statistic: returns data and mapping unchanged.
stat-manual - Manual statistic: run a closure on the data array inside the layer.
Smoothing and regression
stat-quantile - Quantile regression statistic: fit one line per τ and sample it.
stat-smooth - Smoother statistic: closed-form linear fit with a pointwise confidence band.
Summaries
stat-count - Count statistic: one output row per distinct x level with y = count.
stat-sum - Sum statistic: one output row per unique (x, y) pair with _n and _prop.
stat-summary - Per-axis reduction to a central value and an uncertainty band.