Statistics and Data Analysis for
Social Science
Eric J. Krieg
Chapter 3
Measures of Central Tendency
Copyright © 2012 Pearson Education, Inc. All rights reserved.
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10
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Frequency
9
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The Normal Distribution – the Bell Curve
Using a Dot Plot we can see what is below the shape of the bell curve. Each dot represents a data point. The height of the curve tells us how many of each value that we have. If we were to connect the top dots, we would generate the bell shape of the normal distribution
Copyright © 2012 Pearson Education, Inc. All rights reserved.
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10
20
30
40
50
60
70
80
1 2 3 4 567 8
Frequency
9
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The Normal Distribution – the Bell Curve
Measures of center are about the values that are in the center of the distribution – where the most data is found
Copyright © 2012 Pearson Education, Inc. All rights reserved.
1
1/3/2015
Symbols used in Chapter 3
Mode
(book uses Mo – others just list as Mode)
Median
(book uses Md – others just list Median)
Mean of sample