Estadistica

Contents
1 Introduction to Statistics and Data Analysis 1
2 Probability 11
3 Random Variables and Probability Distributions 29
4 Mathematical Expectation 45
5 Some Discrete ProbabilityDistributions 59
6 Some Continuous Probability Distributions 71
7 Functions of Random Variables 85
8 Fundamental Sampling Distributions and Data Descriptions 91
9 One- and Two-Sample Estimation Problems103
10 One- and Two-Sample Tests of Hypotheses 121
11 Simple Linear Regression and Correlation 149
12 Multiple Linear Regression and Certain Nonlinear Regression Models 171
13 One-FactorExperiments: General 185
14 Factorial Experiments (Two or More Factors) 213
15 2k Factorial Experiments and Fractions 237
16 Nonparametric Statistics 257
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iv CONTENTS
17 Statistical Quality Control 27318 Bayesian Statistics 277
Chapter 1
Introduction to Statistics and Data
Analysis
1.1 (a) 15.
(b) ¯x = 1
15 (3.4 + 2.5 + 4.8 + · · · + 4.8) = 3.787.
(c) Sample median is the 8th value, afterthe data is sorted from smallest to largest:
3.6.
(d) A dot plot is shown below.
2.5 3.0 3.5 4.0 4.5 5.0 5.5
(e) After trimming total 40% of the data (20% highest and 20% lowest), the databecomes:
2.9 3.0 3.3 3.4 3.6
3.7 4.0 4.4 4.8
So. the trimmed mean is
¯xtr20 =
1
9
(2.9 + 3.0 + · · · + 4.8) = 3.678.
1.2 (a) Mean=20.768 and Median=20.610.
(b) ¯xtr10 = 20.743.
(c) A dot plot isshown below.
18 19 20 21 22 23
1
2 Chapter 1 Introduction to Statistics and Data Analysis
1.3 (a) A dot plot is shown below.
200 205 210 215 220 225 230
In the figure, “×” represents the “Noaging” group and “◦” represents the “Aging”
group.
(b) Yes; tensile strength is greatly reduced due to the aging process.
(c) MeanAging = 209.90, and MeanNo aging = 222.10.
(d) MedianAging = 210.00, andMedianNo aging = 221.50. The means and medians for
each group are similar to each other.
1.4 (a) ¯XA = 7.950 and ˜XA = 8.250;
¯X
B = 10.260 and ˜XB = 10.150.
(b) A dot plot is shown below....