Basic Statistics

viii CONTENTS

6.4.

6.4.

Using Histograms and Box Plots

Using Normal Probability Plots or Quantile-Quantile

Plots

6.5 Transformations

6.5.1 Finding a Suitable Transformation

6.5.

Problems

References

Assessing the Need for a Transformation

7 Estimation of Population Means: Confidence Intervals

7.

7.

7.

7.

7.

7.

Confidence Intervals

7.1.1 An Example

7.1.2 Definition of Confidence Interval

7.1.3 Choice of Confidence Level

Sample Size Needed for a Desired Confidence Interval

The t Distribution

Confidence Interval for the Mean Using the t Distribution

Estimating the Difference Between Two Means: Unpaired Data

7.5.1 The Distribution of - 7,

7.5.

7.5.

Estimating the Difference Between Two Means: Paired

Comparison

Problems

References

Confidence Intervals for ,LL~ - p2: Known Variance

Confidence Intervals for ,LL~ - p2: Unknown Variance

8 Tests of Hypotheses on Population Means

8.

8.

8.

8.

Tests of Hypotheses for a Single Mean

8.1.1 Test for a Single Mean When u Is Known

8.1.2 One-sided Tests When u Is Known

8.1.3 Summary of Procedures for Test of Hypotheses

8.1.4 Test for a Single Mean When Is Unknown

Tests for Equality of two Means: Unpaired Data

8.2.

8.2.

Testing for Equality of Means: Paired Data

Concepts Used in Statistical Testing

8.4.

Testing for Equality of Means When u Is Known

Testing for Equality of Means When 0 Is Unknown

Decision to Accept or Reject

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