multiverse: Multiplexing Alternative Data Analyses in R Notebooks

There are myriad ways to analyse a dataset. But which one to trust? In the face of such uncertainty, analysts may adopt multiverse analysis: running all reasonable analyses on the dataset. Yet this is cognitively and technically difficult with existing tools—how does one specify and execute all combinations of reasonable analyses of a dataset?—and often requires discarding existing workflows. We present multiverse, a tool for implementing multiverse analyses in R with expressive syntax supporting existing computational notebook workflows. multiverse supports building up a multiverse through local changes to a single analysis and optimises execution by pruning redundant computations. We evaluate how multiverse supports programming multiverse analyses using (a) principles of cognitive ergonomics to compare with two existing multiverse tools; and (b) case studies based on semi-structured interviews with researchers who have successfully implemented an end-to-end analysis using multiverse. We identify design tradeoffs (e.g. increased flexibility versus learnability), and suggest future directions for multiverse tool design.