Basic Statistics

CONTENTS vii

4.1.2 Stem and Leaf Tables

4.1.3 The Frequency Table

4.1.4 Relative Frequency Tables

4.2.

4.2.

4.2.3 Areas Under the Histogram

4.2.4 The Frequency Polygon

4.2.

4.2.6 Distribution Curves

Problems

References

4.2 Graphs

The Histogram: Equal Class Intervals

The Histogram: Unequal Class Intervals

Histograms with Small Class Intervals

5 Measures of Location and Variability

5.

5.

5.

5.

5.

Measures of Location

5.1.1 The Arithmetic Mean

5.1.2 The Median

5.1.3 Other Measures of Location

Measures of Variability

5.2.

5.2.2 Other Measures of Variability

Sampling Properties of the Mean and Variance

Considerations in Selecting Appropriate Statistics

5.4.1 Relating Statistics and Study Objectives

5.4.2 Relating Statistics and Data Quality

5.4.3 Relating Statistics to the Type of Data

A Common Graphical Method for Displaying Statistics

Problems

References

The Variance and the Standard Deviation

6 The Normal Distribution

6.

6.

Properties of the Normal Distribution

Areas Under the Normal Curve

6.2.

6.2.2 Linear Interpolation

6.2.3 Interpreting Areas as Probabilities

Importance of the Normal Distribution

Computing the Area Under a Normal Curve

6.

6.4 Examining Data for Normality

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