rSRD: An R package for the Sum of Ranking Differences statistical procedure

Abstract

Sum of Ranking Differences (SRD) is a relatively novel, non-para-metric statistical procedure that has become increasingly popular recently. SRD compares solutions via a reference by applying a rank transformation on the input and calculating the distance from the reference in $L_1$ norm. Although the computation of the test statistics is simple, validating the results is cumbersome -- at least by hand. There are two validation steps involved. Comparison of Ranks with Random Numbers, which is a permutation-test, and cross-validation combined with statistical testing. Both options impose computational difficulties albeit different ones. The rSRD package was devised to simplify the validation process by reducing both validation steps into single function calls. In addition, the package provides various useful tools including data preprocessing and plotting. The package makes SRD accessible to a wide audience as there are currently no other software options with such a comprehensive toolkit. This paper aims to serve as a guide for practitioners by offering a detailed presentation of the features.