Untuk kuliah Statistika serta Statistika & Probabilitas

1. Introduction to Probability and Statistics Eleventh Edition Robert J. Beaver • Barbara M. Beaver • William Mendenhall Presentation designed and written by: Barbara M. Beaver with minor change by Joon Jin Song

2. Introduction to Probability and Statistics Eleventh Edition Chapter 1 Describing Data with Graphs Some graphic screen captures from Seeing Statistics ® Some images © 2001-(current year) www.arttoday.com

10. Basic Concept Population: the set of all measurements of interest to the investigator Sample: a subset of measurements selected from the population of interest

14. How many variables have you measured? 14 Bus Jr F 2.6 5 15 Eng Fr M 2.7 4 17 Eng So M 2.9 3 15 Math So F 2.3 2 16 Psy Fr F 2.0 1 # of units Major Year Gender GPA Student

15. Types of Variables Qualitative Quantitative Discrete Continuous

21. Graphs Bar Chart: How often a particular category was observed Pie Chart: How the measurements are distributed among the categories

26. Example The prices ($) of 18 brands of walking shoes: 90 70 70 70 75 70 65 68 60 74 70 95 75 70 68 65 40 65 4 0 5 6 5 8 0 8 5 5 7 0 0 0 5 0 4 0 5 0 8 9 0 5 4 0 5 6 0 5 5 5 8 8 7 0 0 0 0 0 0 4 5 5 8 9 0 5 Reorder

29. Interpreting Graphs: Shapes Mound shaped and symmetric (mirror images) Skewed right: a few unusually large measurements Skewed left: a few unusually small measurements Bimodal: two local peaks

36. 4% 2/50 = .04 2 11 65 to < 73 14% 7/50 = .14 7 1111 11 57 to < 65 18% 9/50 = .18 9 1111 1111 49 to < 57 26% 13/50 = .26 13 1111 1111 111 41 to < 49 28% 14/50 = .28 14 1111 1111 1111 33 to < 41 10% 5/50 = .10 5 1111 25 to < 33 Percent Relative Frequency Frequency Tally Age

37. Shape? Outliers? What proportion of the tenured faculty are younger than 41? What is the probability that a randomly selected faculty member is 49 or older? Skewed right No. (14 + 5)/50 = 19/50 = .38 (8 + 7 + 2)/50 = 17/50 = .34 Describing the Distribution