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Applied Statistical Methods
Larry Winner Department of Statistics University of Florida February 23, 2009

2

Contents
1 Introduction 1.1 Populations and Samples . . . . . . . . . . . 1.2 Types of Variables . . . . . . . . . . . . . . . 1.2.1 Quantitative vs Qualitative Variables 1.2.2 Dependent vs Independent Variables . 1.3 Parameters and Statistics . . . . . . . . . . . 1.4 Graphical Techniques . . . . . . . . . . . . . 1.5 Basic Probability . . . . . . . . . . . . . . . . 1.5.1 Diagnostic Tests . . . . . . . . . . . . 1.6 Exercises . . . . . . . . . . . . . . . . . . . . 7 7 8 8 9 10 12 16 20 21 25 25 29 29 29 32 32 32 32 32 35 35 37 38 38 39 40 42 42 44 48

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2 Random Variables and Probability Distributions 2.1 The Normal Distribution . . . . . . . . . . . . . . . . . . 2.1.1 Statistical Models . . . . . . . . . . . . . . . . . 2.2 Sampling Distributions and the Central Limit Theorem 2.2.1 Distribution of Y . . . . . . . . . . . . . . . . . . 2.3 Other Commonly Used Sampling Distributions . . . . . 2.3.1 Student’s t-Distribution . . . . . . . . . . . . . . 2.3.2 Chi-Square Distribution . . . . . . . . . . . . . . 2.3.3 F -Distribution . . . . . . . . . . . . . . . . . . . 2.4 Exercises . . . . . . . . . . . . . . . . . . . . . . . . . .

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