Math 143 C/E, Spring 2001
IPS Reading Questions
Chapter 2, Section 6

1. How many variables go in to making a two-way table? What types of variables are they, generally (choose here between categorical or quantitative)? How many values are these variables allowed to take?

   
   
   
   
   
   
   
   

2. The ``Total" row and column (excluding the `grand total' where these two meet) are called marginal distributions. The fact that they are called `distributions' makes more sense when you look at the bar graph on p. 195 (Fig. 2.38), which is more in line with what we have called a distribution in the past. Make sure you see the relationship between Fig. 2.38 and the marginal distribution in the ``Total" column of Table 2.14 (p. 194).
3. Starting with a 2-way table, how does one form a column percent in a cell? How about a row percent? Would it make sense to look at a bar graph of these column (or row) percents when the column (or row) is not a ``Total"?

   
   
   
   
   
   
   
   

4. What is the lesson from the example of Simpson's paradox (p. 199)?