ATPA: Reproducibility starts before the modelling step
A reproducible analysis records the data version, preprocessing, model settings and the environment needed to rerun it. Reproducibility does not mean a model is valid, but it lets someone investigate why results differ.
Worked example or practice scenario
On an original practice dataset, keep raw inputs unchanged; save a scripted transformation; record package versions and random seeds where relevant; and generate the tables used in the report from that transformation. Avoid a manually edited table with no traceable source.
Try this next
Rerun from a clean session and compare row counts, summaries and reported outputs. Explain any intentional variation. Prepare this workflow on allowed practice material, and verify assessment-specific permissions directly rather than assuming that all helpful tools are permitted.
Reading sources
ActNet editorial guide · October 1, 2026 · Original illustrative examples.