# Interpret data to support decisions · Working guide

Version 1 · 13 October 2026. Classroom material: all data are fictional. Reference edition: eight hours across four two-hour sessions. Practice and feedback are included in those hours. The trainer will review tasks, tools and timings before delivery.

## How to use the files

1. Open `commercial-case.csv` in the agreed tool. Retain an original copy and read `dictionary.md` before changing values.
2. Use `worksheet.md` to record your question, period, unit and criterion. Record what you correct and why; do not fill a blank by intuition.
3. Compare counts and rates with their bases. If you draw wins as bars, start the axis at zero and retain the table’s counts and denominators.
4. Open `operations-case.csv`: calculate only where a measurement exists and check the request mix. State how many records are omitted from the calculation.
5. Write a focused decision with an observation, uncertainty and next check. Compare with `worked-examples.md` after your first attempt.
6. Complete `individual-case.csv` using `assessment.md`; the trainer applies the rubric and gives feedback. Reading a solution does not establish that the practice has been passed.

## Four sessions

1. **Define the question and prepare the source · 2 h.** Agree the entity, period, snapshot and status definitions; review the sales rows and retain data-quality decisions. A focused question, short dictionary and 20 unique opportunities with the unknown status visible.
2. **Compare channels without switching the base · 2 h.** Calculate counts and rates, distinguish their denominators and correct a display that exaggerates a difference. A verifiable sales comparison with bases and open or unknown outcomes identified.
3. **Read the operational process · 2 h.** Calculate times only where measured, group by request type and review the changing work mix between weeks. An explanation that distinguishes the observed average, work composition and missing time measurement.
4. **Defend a decision and review another sample · 2 h.** Prepare the final note, complete the individual variation and check calculations and limits with trainer feedback. A traceable recommendation and reviewed individual practice with a defined next check.

## Tool and access

The method does not depend on a particular platform. Reading, calculations and presentation are adapted to the tool the team uses or completed using the classroom tables. CSVs are classroom tables, not production connections or importers. If a chart function is unavailable, prepare a table and annotated sketch, noting which feature was not executed. AI is optional. Any calculation or explanation draft is checked against the rows and definitions.

If a file fails to open, record the file, action and error without adding sensitive information. The trainer agrees a tabular reading alternative. Do not upload company data to an unauthorised tool or present classroom practice as a real business outcome.

## Submission

Analysis worksheet, reproducible calculations, table or chart and a decision note. Materials contain examples, but the individual submission must show your decisions. No additional mandatory work between sessions is required.

[Download ZIP pack](data-en-v1.zip)