Who and what are being described?
1A–1C
The lecture's summary context becomes a denominator check: all student rows for a response rate, recorded ratings for an observed mean.
Week 2: measurement and summary context; Week 1 rows and types
Your task
Identify the row unit, count recorded and missing satisfaction, and compare category labels with measurements.
Evidence to include
Use your valid n, missing count and response table. Explain why missing ratings are not zero.
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 2 notebook1 · Who and what are we describing? (10 min)
One row is one synthetic student observed in the same week. Scores are points out of 100; minutes are minutes per student in that week. Satisfaction is an ordered category from 1 (lowest) to 5 (highest); equal numerical steps need not represent equal changes in feeling. Programme A/B are category labels; record IDs are identifiers.
The next cell displays the data and counts. count() excludes missing values; len() counts rows. No missing value is replaced by zero.
Python · cell 4 — read here, run in your notebook
display(students.head())
valid = students['satisfaction'].count()
print(f'Total rows: {len(students)}; valid satisfaction: {valid}; missing: {len(students)-valid}')
print(f'Response rate: {100*valid/len(students):.1f}%')
display(students['satisfaction'].value_counts().sort_index().rename('responses'))
print('Most common programme(s):', students['programme'].mode().tolist())Your reasoning
1A. State the observational unit and the denominator for the satisfaction response rate. Why is the denominator for a mean of recorded satisfaction responses different?
1B. A colleague replaces missing satisfaction with zero. Explain why this changes the meaning. Can the responses establish what all students feel?
1C. Which is meaningful: the mode of programme, the mean of record ID, or the mean of programme coded A=1/B=2? Explain. For satisfaction, explain why the category frequency table adds information that a mean alone hides.
Answer: Replace this text with your explanation.
Saved only in this browser. This note doesn’t fill in the downloaded notebook; “reviewed” is a personal checklist, not a grade.