An Introduction to Probability and Statistics

Preface    xv
1    Meaning of Statistics    1
1.1 Introduction............................ 1 

1.2 Why We Care about Statistics.................. 1 

1.3 Descriptive Statistics ....................... 3
1.3.1 Frequency Distribution..................    4 

1.4 Location Measures ........................ 8 

1.4.1 Average .......................... 9 

1.4.2 Weighted Average..................... 10 

1.4.3 Geometric Mean ..................... 10 

1.4.4 Harmonic Mean...................... 11 

1.4.5 Mode............................ 11 

1.4.6 Median .......................... 12 

1.4.7 Quantiles ......................... 13 

1.5 Spread Measures ......................... 13 

1.5.1 Range ........................... 13 

1.5.2 Interquartile Range.................... 14 

1.5.3 Mean Absolute Deviation ................ 15 

1.5.4 Variance.......................... 15 

1.5.5 Standard Deviation.................... 16 

1.5.6 Coefficient of Skewness.................. 16 

1.5.7 Coefficient of Variation.................. 17 

1.6 Covariance and Correlation ................... 18 

1.6.1 Covariance......................... 18 

1.6.2 Correlation ........................ 19 

1.7 Index Numbers .......................... 20 

1.7.1 Simple Index ....................... 20 

1.7.2 Simple Aggregate Index ................. 22 

1.7.3 Aggregate Index ..................... 23 

1.8 Exercises.............................. 23
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