Lab 1 · Section 5 of 6

Compare programmes carefully

Part 5 · TODO 4

First · connect to the lecture

Changing groupby changes the comparison, not its causal strength. Course mix and preparation can still differ between programmes.

2.9 · Lab 1: what you should be able to explain 2.3 · The claim ladder 7.8 · The course-registration example 7.9 · Why stratification does not prove causation

Week 1: claim ladder, PDF pp. 22–29; Week 5 course mix, PDF pp. 38–51

Your task

Change the grouping field to programme. Run the summary and use its table or a chart to describe differences.

Evidence to include

Name the groups and their denominators. Give a plausible alternative explanation for the highest rate.

Notebook questions and code

Read here; run in your downloaded notebook. Start with its setup cells and run in order. Use your own ID and outputs where requested.

Download Lab 1 notebook

Part 5: Small challenge

You have already seen the full pattern. Now change one word in the code below.

The question is: “How do course-registration pass rates differ by programme?”

Replace the blank with the correct grouping column.
Run the cell.
Make a short chart or use the printed table.
Explain why the programme with the highest value is not automatically the “best” programme.

Python · cell 21 — read here, run in your notebook

# TODO 4 - Replace the blank with the correct column name.
# Hint: the column describes Biology, Computer Science, Economics, or Psychology.

challenge_table = (
    joined.groupby(_____)["passed"]
    .agg(n="size", pass_rate="mean")
    .assign(pass_rate=lambda x: (100 * x["pass_rate"]).round(1))
    .reset_index()
)
challenge_table

What did the lab teach you about the lecture?

Saved only in this browser. This note doesn’t fill in the downloaded notebook; “reviewed” is a personal checklist, not a grade.