Imagine someone asking you one of the following requests. If any of these give you a sinking feeling that this is going to be more difficult than it should be, you see the need for reproducible analysis.
The scenarios above come from the presentation Sweave: First Steps Toward Reproducible Analyses by Kevin Coombes. This presentation motivates the need for reproducible analysis and gives an introduction to Sweave, a tool designed to make it easier to reproduce statistical analyses. The talk itself was created from an Sweave document. The source is available at the same link as the talk.
“Microarrays: retracing steps” by Kevin Coombes, Jing Wang, and Keith Baggerly in Nature Medicine, November 2007, pp 1276-1277. The authors report their experience trying to reconstruct the analysis that went into a previous article in the same journal. They recount some of the errors they believe must have occurred and explain why the conclusions are unsupported.
See ReproducibleResearch.org for a list of articles and other resources related to reproducible research.