Math 10, Spring 2019 Introductory Statistics Lecture 2 Summarizing the Distribution of a list of numbers

List of numbers Final exam scores Math 13, winter ’17 75 students 52 47 96 62 42 53 76 41 80 51 70 66 81 71 82 79 49 83 73 89 78 65 56 68 95 58 72 74 63 90 23 44 91 85 30 54 48 69 87 40 77 75 36 88 55 Final exam scores Math 13, winter ’17 75 students Score out of 96

Summary: Table Class intervals: 0-16, 16-32, etc. Endpoint convention: Range of scores Frequency 0-16 16-32 2 32-48 10 48-64 20 64-80 27 80-96 16 Total 75 Class intervals: 0-16, 16-32, etc. Endpoint convention: Right endpoint included in interval

Summary: Histogram

“Drastic” Summary: Statistics Average: 65.4 Standard Deviation: 18.5

Distribution: Table

Distribution: Histogram

Histogram for discrete variable

Average as useful summary Age-specific average heights for men and women age 18-74 in HANES sample.

Average in Histogram

Are mean and SD useful?

SD versus quartiles Average: 65.4 SD: 18.5 Median: 69 Q1: 53 Q3: 79