Math 140E: Test #2 Spring 2008 Page 1 of 6
Your Name: _____________________ ____
Math 140: Statistics
Test 2, March 27, 2008
1. (8 pts.) The correlation coefficient for the first table is 0.7857. Give the correlation
coefficient for each of the remaining tables. You should use either the given
correlation coefficient or your knowledge of correlation coefficients to find these
without doing any real calculations.
x
y
1
2
2
3
3
1
4
4
5
6
6
5
7
7
x1
y1
1
–4
2
–6
3
–2
4
–8
5
–12
6
–10
7
–14
x2
y2
1
6
2
7
3
5
4
8
5
10
6
9
7
11
x3
y3
3
1
4
2
2
3
5
4
7
5
6
6
8
7
x4
y4
1
–1
2
–2
3
–3
4
–4
5
–5
6
–6
7
–7
a) x1 and y1
b) x2 and y2
c) x3 and y3
d) x4 and y4
2. (6 pts.) Find the standard deviation for each of the following sets of data using the
short-cut method presented in Chapter 17:
a) –1, –1, –1, 5, 5, 5
b) 0, 0, 0, 0, 5
