1.	A large study was conducted in downtown area of Vancouver, where there are serious problems with STD's (sexually-transmitted diseases) and drug addiction.

Fill in the rest of the table shown below.  Compute row and column percentages and row and column marginal counts and percentages.
	[5]
count
row%
col%		Drug user			
		yes	no	total	
STD carrier	yes	.
.             %
.             %	60.
.             %
.             %	150.
.             %	
	no	.
.             %
.             %	.
.             %
.             %	220.
.             %	
	total	.
.             %	180.
.             %	

2.	Using the "percentage down compare across" strategy, explain what the table shows.	[3]

A large study was conducted in the Los Angeles area, where there are serious problems with STD's, especially AIDS, and marijuana use. Interview data suggests that marijuana is used by people with advanced AIDS to relieve nausea. 
Fill in the rest of the table shown below.  Compute row and column percentages and row and column marginal counts and percentages. [Keep 3 digits to right of the decimal in the percentages.]	[5]

count
row%
col%		marijuana use			
		yes	no	total	
AIDS	yes	
.           %
.           %	60
38.462%
32.258%	156
41.935%	
	no	
.           %
.           %	
.           %
.           %	216
.           %	
	total	
.           %	186
.           %	

3.	Using the "percentage down compare across" strategy, explain what the table shows.	[4]

4.	Which is more appropriate for this table -- "percentage across, compare down"; or "percentage down, compare across"?    Why?	[3]

5.	Recent medical research indicates that regular consumption of green tea reduces the probability of contacting many types of cancer and cardiovascular disease. Here is a table summarizing the results of a study of 760 people. 	

count
row%
col%		green tea consumer			
		yes	no	total	
cardio-vascular disease	
yes	76
37.25 %
21.714 %	128
62.745 %
31.220 %	204
26 .842 %	
	no	274
49.281 %
78.286 %	282
50.719 %
68.780 %	556
73.158 %	
	total	350
46.053 %	410
53.947 %	760	

a.			Using the "percentage down compare across" strategy, explain what the table shows.	[5]

b.			Which is more appropriate for this table -- "percentage across, compare down"; or "percentage down, compare across"?    Why?	[3]

6.	Recent medical research indicates that regular consumption of blueberries reduces the probability of getting many types of cancer. Here is a table summarizing the results of a study of 600 people.
 	
count
row%
col%		eat blueberries?			
		yes	no	total	
get cancer?	yes	147
55.894 %
49.000 %	116
44.106 %
38.667 %	263
43.833%	
	no	153
45.401 %
51.000%	184
54.599 %
61.333 %	337
56.167 %	
	total	300
50.000 %	300
50.000 %	600	

a.			Using the "percentage down compare across" strategy, explain what the table shows. Make reference to the appropriate percentages in your answer. (eg. “55.894% of those who had cancer ate  blueberries”)	[5]

b.			Which is more appropriate for this table -- "percentage across, compare down"; or "percentage down, compare across"?    Why?	[3]

Questions 7-9 are about the following table which shows data from a study of children’s playing a lot of video games and getting traffic tickets for reckless driving.

count
row%
col%		traffic ticket for reckless driving?			
		yes	no	total	

play a lot of video games?	yes	367
55.271 %
60.862%	297
44.729 %
47.826 %	664
54.248 %	
	no	236
42.143 %
39.138 %	324
57.857 %
52.174 %	560
45.752 %	
	total	603
49.265 %	621
50.735 %	1224	

7.	The independent variable is:
a.	getting  traffic tickets/not getting  traffic tickets
b.	playing a lot of video games/not playing a lot of video games

8.	The “42.143%” in the first column means that:

a.	42.143 percent of the people in this study don’t play a lot of video games and do get tickets
b.	42.143 percent of people who don’t play a lot of video games get tickets for reckless driving
c.	42.143 percent of people who get tickets for reckless driving don’t play a lot of video games
d.	42.143 percent of people who play a lot of video games don’t get tickets for reckless driving
e.	None of the above

9.	Which method is more appropriate for reading this table?
a.	Percentage down compare across
b.	Percentage across compare down
c.	It doesn’t matter for this table
d.	I need more information about the study before I can answer that question