What are the benefits of a written data analysis plan?

A written data analysis plan (document) is commonly developed that outlines specific tasks and expected time requirements. Recording the plan has several benefits:
(1 ) it forces the analyst to explicitly consider constraints;
(2 ) it helps the analyst to remain on task, avoiding any unnecessary efforts that consume valuable time and resources;
(3 ) it provides a standard against which to monitor the progress of the data analysis; and
(4 ) it facilitates a detailed description of the analysis, which is a necessary component for communicating results at the completion of the engagement.

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