Week 7

Inference for difference in means, one proportion, and difference in proportions, and power
Published

November 10, 2025

Modified

November 13, 2025

Overview of Week 7

Mon: Day 11

  • Inference for difference in means from two independent sample (2-sample t-test)
  • Power and sample size calculations

Wed: Day 12

  • Inference for proportions
    • CIs vs. hypothesis tests
    • One proportion from one sample
    • Difference in proportions from two independent samples

Slides & Recordings

Day Topic Slides: html Slides: pdf Slides: web-page Slides with notes Recording Link Duration Code: qmd Code: html
11 2-sample means test: 5.3.2 Day 11: slides 1-17 Day 11 Part 1 36 min
2-sample means CI; R; pooled SD: 5.3.1, 5.3.5 Day 11: slides 18-26 same same Day 11 Part 2 26 min same same
Power & sample size: 1 or 2 means: 5.4 & extra Day 11: slides 27-45 same same Day 11 Part 3 57 min same same
12 1 & 2 proportions test & CI: 8.1.1, 8.2 Day 12: slides 1-23 * * Day 12 Part 1 48 min
R: 1 & 2 proportions test & CI Day 12: slides 24-34 same same Day 12 Part 2 26 min same
Power for 1- and 2- proportions Day 12: slides 35-43 same same Day 12 Part 3 25 min same

*Note: page numbers in pdf files do not always align with those in the original html slides

Datasets

All datasets can be found on GitHub

Practice Problems

Day 11 PP

  • Book exercises: 5.34, 4.22

Day 12 PP

  • Book exercise: 8.2

Class discussion

During class you will be working in groups discussing the following:

Day 11

  • Practice Problems listed above
  • Book 5.26 a-b
  • R2: DDS expenditures by ethnicity (parts A-L)
  • PSS1: Book 4.24 - Power & sample size T/F questions
  • PSS2: Power & sample size calculations

Day 12

Coming soon!

  • Practice Problems listed above
  • Book
    • 8.8 (see instructions in HW),
    • 8.24 (see instructions in HW)

Homework

  • HW 4 covers Days 10-12 and is due on Sat, 11/15
  • Check out this spreadsheet for typos in book.