Midterm Exam
Thursday, October 29
The midterm is in class on Thursday, October 29, and covers Chapters 2–5.
The midterm, with solutions, is posted here: midterm-sols.pdf.
Format
Think of the midterm as a big quiz. You will have 75 minutes for 4 questions, each drawn from the homework problems listed below, with possible minor variations or extensions.
The exam is closed note. You may bring a four-function calculator. However, you’ve seen the homework problems, you will likely not need one.
Problems you are responsible for
| Homework | Problems |
|---|---|
| Week 1 | 3, 4 |
| Week 2 | 1, 3, 4 |
| Week 3 | 1, 2, 3, 4 |
| Week 4 | 1, 3, 4 (parts 1–2 only) |
| Week 5 | 1, 2, 4 (parts 1–2 only) |
| Week 6 | 1, 2 |
Provided on the exam
If a question needs them, the following will be printed on the exam, so you do not need to memorize them. You should still know how to use them.
- Week 3, Problem 3: the definitions of total and retained variance and of reconstruction error.
- Week 4, Problems 3 and 4: the definition of the mean and covariance of a random vector.
- Week 4, Problem 4: the standard assumptions (A1)–(A3) and means and covariances under linear maps.
- Week 5, all problems: the ridge solution and ridge regression filters the singular values.
- Week 6, all problems: Lloyd’s algorithm, the definition of \(\operatorname{opt}_k\), and the lemma for the sum of squares around a point.
How to prepare
The most important thing you can do is write clean solutions, in your own words, to every problem listed above. More that just writing them, in my opinion you understand a problem once you can confidently explain it, start to finish, without looking at your notes. Since the exam may vary or extend a problem, a memorized solution will likely not be enough, though the homework problems themselves will make up around ~80% of the grade.
Testing accommodations
If you take exams with accommodations through the StAAR Center, you must book at least three business days before the exam, that is, by Monday, October 26 at the latest. It is best to book this week.