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Statistics First Five

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Submitted By afabianova
Words 11010
Pages 45
An Introduction to
Statistics
Keone Hon
<keone.hon@gmail.com>

Contents
1 Descriptive Statistics

2

1.1

Descriptive vs. Inferential . . . . . . . . . . . . . . . . . . . . . .

2

1.2

Means, Medians, and Modes . . . . . . . . . . . . . . . . . . . . .

2

1.3

Variability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4

1.4

Linear Transformations . . . . . . . . . . . . . . . . . . . . . . .

5

1.5

Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6

1.6

Dispersion Percentages . . . . . . . . . . . . . . . . . . . . . . . .

7

2 Graphs and Displays
2.1

9

Histograms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9

2.1.1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . .

9

2.1.2

Medians, Modes, and Means Revisited . . . . . . . . . . .

10

2.1.3

z-Scores and Percentile Ranks Revisited . . . . . . . . . .

11

2.2

Stem and Leaf Displays . . . . . . . . . . . . . . . . . . . . . . .

11

2.3

Five Number Summaries and Box and Whisker Displays . . . . .

12

3 Probability

13

3.1

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

13

3.2

Random Variables . . . . . . . . . . . . . . . . . . . . . . . . . .

16

3.2.1

Definition . . . . . . . . . . . . . . . . . . . . . . . . . . .

16

3.2.2

Expected Value . . . . . . . . . . . . . . . . . . . . . . . .

17

3.2.3

Variance and Standard Deviation . . . . . . . . . . . . . .

17

3.2.4

“Shortcuts” for Binomial Random Variables . . . . . . . .

18

1

4 Probability Distributions

19

4.1

Binomial Distributions . . . . . . . . . . . . . . . . . . . . . . . .

19

4.2

Poisson Distributions . . . . . . . . . . . . . . . . . . . . . . . . .

21

4.2.1

Definition . . . . . . . . . . . . . . . . . . . . . . . . . . .

21

4.2.2

As an Approximation to the Binomial . . . . . . . . . . .

22

Normal Distributions . .

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