Doubly ranked tests are nonparametric tests for grouped functional and multivariate data. The testing procedure first ranks a matrix (or three dimensional array) of data by column (if a matrix) or by cell (across the third dimension if an array). By default, it calculates a sufficient statistic for the subject's order within the sample using the observed ranks, taken over the columns or cells. Depending on the number of groups, G, the summarized ranks are then analyzed using either a Wilcoxon Rank Sum test (G = 2) or a Kruskal-Wallis (G greater than 2).
An R Package that contains code to run Doubly Ranked Tests (DRTs) as described by Meyer (2024). DRTs are non-parametric tests that can be used to compare groups of curves or surfaces.
Run the following code:
install.packages("devtools")
devtools::install_github("markjmeyer/runDRT")