Diagnostic Tool by Multiple Imputation for Regression Discontinuity Designs // Estimates average treatment effects at the cutoff based on sharp regression discontinuity designs (RDD) and multiple imputation regression discontinuity designs (MIRDD). It provides diagnostic tools for RDD by comparing results with those from MIRDD, as proposed in Takahashi (2023) doi:10.1080/03610918.2021.1960374. The package includes datasets from Takahashi (2023) and Takahashi (2026) doi:10.1016/j.softx.2026.102707.