PDF Archive

Easily share your PDF documents with your contacts, on the Web and Social Networks.

Chapter 8.pdf

Page 1 234120

Text preview

VII!. ANALYZE

BOK
l{f,A.2

trllEAS URI NG RELATIONSHIPS/REGRESSTON

Simple Linear Regression Model (Continued)
Student

Study Time (Hours)

Test Results (%)

60h
40h
50h
65h
35h
40h
50h
30h
45h
55h

1

2
3

4
5
6
7
8

I

10

67o/o
61o/o

73o/&quot;
80o/o

60%
55o/o
620/o
50o/o

61olo

70%

Table 8.1 Study Time Versus Test Results
An initial approach to the analysis of the data in Table 8.1 is to plot the points on a
graph known as a scatter diagram, as shown in Figure 8.2. Observe that y appeanr
to increase as x increases. One method of obtaining a prediction equation relating
y to x is to place a ruler on the graph and move it about until it seems to pass
through the maiority of the points, thus providing what is regarded as the &quot;best fit&quot;
line.

81

'^7r
o
=o67

to

660
o
F
53

30 35 40 45 50 55 60

65

Study Time (Hours), X

Figure 8.2 Plot of Study Time Versus Test Results

CSSBB 2014

vilt -3

@

QUALITY COUNCIL OF INDIANA