Test 2 Review

Test Reviews:

This Test Review is not intended to replace doing the lessons, reading the text, and doing the homework These are not lists of objectives for the chapters nor are they complete lists of the topics. The textbook and homework provide those. The Test Review focuses on topics and problems that students in previous semesters have been somewhat more likely to make mistakes on than the rest of the material.

It is pointless to even read these questions until you have read the chapters and done the homework. After that, you might want to write out answers to the questions (maybe conferring with other students in your class) and then bring the questions and your answers to the instructor or a tutor so that they can help you with any misunderstandings you have.

Test 2:

While each test focuses on the new material since the last test, the material in this course is comprehensive, so tests can be comprehensive. In particular, everything in Chapter 4 is very much relevant to all the new material in Chapter 5, so you should think of Chapter 4 as being fully included on this test. Chapters 1 and 2 are about summarizing data numerically and graphically, so that is still very relevant for Test 2 and all tests later in the course. We do not use the material in Chapter 3 again on new topics until Chapter 10, but it is important not to forget it. It will be very important in the last half of the course.

In the Review Chapters (Chapter 7 and 16) you can find lists of topics. You should now know how to do everything in the Chapter 7 summaries and, in Chapter 16, sets A and B. Look at these lists and make sure you remember how to do each of these. Start a list of what you will need in your notes to remind you of formulas or definitions you're having trouble remembering.

If you need more details about some of these, including formulas, look in the Chapter Summary at the end of the appropriate chapter.

The Lesson overviews that I wrote, and that are provided at the beginning of each lesson are not intended to be useful for the main test over that material. They are intended to be useful as you go further in the course and are trying to remember what it is that you were supposed to remember from chapters earlier in the course. So they are somewhat shorter.

Then look over the following comments about things that students sometimes miss on the new material for Test 2 to make sure you understand these.

1. Make a scatterplot. Know which variable (response or explanatory) goes on which axis.
2. Interpret the correlation coefficient.
3. Given a scatterplot, be able to make a reasonable estimate of the correlation coefficient. (It doesn't have to be terribly accurate -- but with the correct sign and correct as to whether it is close to 1 or to 0.) Do not confuse this with computing the correlation coefficient. That's very different!
4. Chapters 4 and 5 go together well. Be prepared to take a set of data and compute everything we learned to compute in this chapter and interpret all of it. Sometimes students forget to study the interpretation of the slope coefficient and the intercept.
5. Computations: You must be able to use your calculator to compute means. Recall that we don't compute the standard deviations or r, the correlation coefficient, by hand. I'll give you those. Be sure that you can compute the regression coefficients by hand, using a simple calculator from the means, standard deviations, and r. If you just give me the final result, without the formulas to show how you computed it, you will get no credit.
6. Distinguish between quantitative and categorical data and know which techniques are appropriate to analyze which types of data.
7. Determine from the statement of the problem which variable should be the response variable and know what that means for scatterplots and the regression equation.
8. Compute conditional distributions and marginal distributions and graph these.
9. Answer various questions about two-way tables.
10. Take the data in a three-way table and produce a two-way table of the type requested from it.
11. Answer questions involving Simpson's Paradox.
12. Be sure that you can distinguish between the population and the sample. Is the sample the ones you selected, or the ones you actually observed? (I.e., do "nonrespondents" count as part of the sample, according to the definitions here?)
13. List the types of sampling discussed in our text and discuss the strengths and drawbacks of each.
14. Is a stratified random sample the same as a simple random sample?
15. Draw a diagram of your experimental design. Use the "jargon" of experimental design correctly, such as factors, treatments, etc.
16. Identify and discuss the three main principles of experimental design.
17. For a given question, describe a good sampling design or a good experimental design, as appropriate.
18. Identify problems with, and answer questions about, a given sampling design or experimental design.

This was last updated on September 4, 2009 . Mary Parker, mparker@austincc.edu