diff_diff.RDPlot#

class diff_diff.RDPlot[source]#

Bases: object

Data-driven RD plot builder (CCT 2015; rdrobust 4.0.0 rdplot() parity).

Parameters mirror R’s rdplot() and keep its defaults - including kernel="uniform" and p=4, which deliberately differ from RegressionDiscontinuity’s estimation defaults (triangular, p=1): the global fit is a descriptive overlay, not the local RD estimator.

Parameters:

  • cutoff (float, default 0.0) – Threshold in the running variable.

  • p (int, default 4) – Order of the global polynomial fits (R accepts any integer >= 0).

  • nbins (int or (int, int), optional) – Manual number of bins per side; overrides the data-driven selector. Any positive count is accepted (R permissiveness); note that very large bin counts allocate proportional jump grids and, with covariates, a dense per-side bin-dummy matrix (documented performance seam).

  • binselect (str, default "esmv") – One of es, espr, esmv, esmvpr, qs, qspr, qsmv, qsmvpr - partition scheme (evenly/quantile spaced) x target (IMSE-optimal / mimicking variance) x variance estimator (spacings / polynomial regression). The spacings variants assume a continuously distributed OUTCOME (CCT 2015 Theorems 3-4); heavy outcome ties trigger a warning recommending the *pr sibling. QS cutpoints follow R: quantile type-7 interpolation, not the paper’s inf-form empirical inverse (documented deviation-from-paper inherited from rdrobust).

  • scale (float or (float, float), optional) – Multiplies the selected number of bins (undersmoothing knob). A fractional product is resolved with the ceiling of CCT 2015 Equation 2. Deviation from R: rdrobust 4.0.0 crashes on fractional products (vector-indexing accident) and rejects a length-2 scale outright on R >= 4.2 (vectorized-if error); both surfaces work here.

  • kernel (str, default "uniform") – Weighting for the global polynomial fit within h.

  • h (float or (float, float), optional) – Window for the global fit; default is each side’s full range.

  • support ((float, float), optional) – Extended support for bin construction; only WIDENS the observed range (R semantics).

  • masspoints (str, default "adjust") – "check" warns when either side has >= 20% duplicate running values; "adjust" additionally switches a spacings binselect to its polynomial-regression sibling; "off" disables detection.

  • ci (float, optional) – Confidence level (percent) for the per-bin intervals drawn by RDPlotResult.plot(). CI columns are ALWAYS computed (at 95 when ci is None, matching R); ci only sets the level and turns the error bars on.

  • covs_drop (bool, default True) – Drop redundant covariates (R’s pipeline: stable name-length sort + LINPACK-style QR check) with a warning naming the dropped columns; False raises a deterministic error on collinear covariates.

Methods

__init__([cutoff, p, nbins, binselect, ...])

fit(data, outcome_col, running_col[, covariates])

Build the RD plot quantities.

get_params()

Get parameters of this plot builder.

set_params(**params)

Set parameters (transactional: validates the full candidate configuration before mutating this instance).
__init__(cutoff=0.0, p=4, nbins=None, binselect='esmv', scale=None, kernel='uniform', h=None, support=None, masspoints='adjust', ci=None, covs_drop=True)[source]#
Parameters:
classmethod __new__(*args, **kwargs)#