Week 8

Chi-squared tests and ANOVA
Published

November 17, 2025

Modified

November 18, 2025

Overview of Week 8

HW 5 covers Day 13 and is due on THURSDAY, 11/20

Mon: Day 13

  • Chi-squared tests of association and homogeneity
  • Fisher’s exact test
  • Sections 8.3-8.4

Wed: Day 14

  • ANOVA = Analysis of Variance
  • Comparing more than 2 means
  • Section 5.5

Slides & Recordings

Day Topic Slides: html Slides: pdf Slides: web-page Slides with notes Recording Link Duration Code: qmd Code: html
13 Chi-sqr intro Day 13: slides 1-10 Day 13 Part 1 18 min
Chi-sqr test: 8.3.1 - 8.3.4 Day 13: slides 11-17 same same Day 13 Part 2 23 min same
Chi-sqr in R, Fisher’s Exact Test, Chi-sqr vs. prop’s Day 13: R tip, slides 18-33 same same Day 13 Part 3 57 min same
14 ANOVA intro Day 14: slides 1-15 Day 14 Part 1 29 min
ANOVA table Day 14: slides 16-28 same same Day 14 Part 2 27 min same
ANOVA in R, conditions, post-hoc testing Day 14: slides 29-47 same same Day 14 Part 3 39 min same

Datasets

All datasets can be found on GitHub

Practice Problems

Day 13 PP

  • Book exercises:
    • 8.28
    • 8.24 (a) & (b) as a test of independence (for HW 4 I had you test the difference in proportions)

Day 14 PP

  • Slide 12: “Hypothetical examples” question
  • Slide 29 questions
  • Book exercise: 5.48

Class discussion

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

Day 13

  • Practice Problems listed above
  • Questions from HW 5 (due THURSDAY)
    • Book: 8.32, 8.34, 8.38 (all have special instructions; see assignment)

Day 14

  • Practice Problems listed above
  • Questions from HW 6
    • Book 5.44
    • R1: Palmer Penguins ANOVA

Homework

  • HW 5 covers Day 13 and is due on THURSDAY, 11/20
  • HW 6 covers Days 14-15 and is due on Sat, 11/29
  • Check out this spreadsheet for typos in book.

Exam 3 information

  • Exam 3 will be on Mon, Nov. 24th
  • Samples of past exam questions and answers (on Sakai)
    • Note: I still need to add the answers for the Fall 2024 exam.
  • Material will cover Days 10-13,
    • which is approximately Sections 4.3, 5.1-5.4, and 8.1-8.4 from the textbook, plus supplementary material.
  • The exam will be in-class and handwritten. Bring a calculator.
  • You may bring one page of notes on an 8.5” x 11” sheet of paper.
    • You may use both sides.
    • You may type your notes.
    • You may not use screenshots of the notes or textbook
    • You will be turning in the page of notes with the exam, so please add your name to the sheet.