Module 01 Activity

Scenario

You have been asked to test whether a change worked. Set the project up so the answer is checkable by somebody who does not trust you.

What you build

A statistical project skeleton with a dated analysis plan, a script that computes and a report that only cites.

Steps

1. Write the analysis plan first: question, outcome, unit, comparison, primary test, significance level and sidedness. Date it.
2. Create the folders, including one for the plan, and put the raw data where code never writes.
3. Put set.seed() once at the top of the analysis script and record the value in the report.
4. Build the analysis table explicitly — the planned columns only, the grain set, grouping variables as factors with deliberate levels.
5. Encode every exclusion as a named constant with its reason, and print how many rows it removed from each group.
6. Tidy every planned test into one results table, then write the interpretation separately without re-selecting rows.

Evidence to hand in

• The dated analysis plan.
• The folder listing.
• The analysis table, with what was dropped from raw.
• The exclusion rules and their row counts.
• The results table covering every planned comparison.
• The interpretation section.

Review checklist

• The plan predates the analysis and names the primary test and alpha.
• The seed is set once and its value appears in the report.
• Every column in the analysis table was named in the plan.
• Every exclusion is a named constant with a printed row count.
• The results table contains all planned comparisons, not only the significant ones.

Mark complete