loo_donors: Leave-One-Out Donor Robustness for SCM

In coresynth: Fast and Unified Synthetic Control Methods

Leave-One-Out Donor Robustness for SCM

Description

Iteratively re-estimates the synthetic control excluding one contributing donor at a time, holding the predictor weights V fixed at their baseline values (Abadie, Diamond & Hainmueller 2015, footnote 20). The spread of the leave-one-out ATT estimates shows how much the result hinges on any single donor.

Usage

loo_donors(fit, weight_threshold = 1e-06)

Arguments

fit	A sharp coresynth object from scm_fit() with method = "scm".
weight_threshold	Only donors whose baseline weight exceeds this value are dropped (removing a zero-weight donor cannot change the fit). Default 1e-6.

Details

For penalised fits (lambda_pen used), the same penalty is re-applied in each leave-one-out QP.

Value

A list with:

• att_original: baseline ATT

• results: data.frame with one row per excluded donor (donor, weight, att_loo)

• att_range: range of the leave-one-out ATTs

See Also

placebo_in_time(), mspe_ratio_pval()

coresynth documentation built on Aug. 28, 2026, 1:06 a.m.