Chapter 2.1（课件）- 《统计学基础（英文）》同步教学（人民大学·第7版）

Elementary Statistics Seventh Edition Chapter 2 Descriptive Statistics Copyright 2019, 2015, 2012, Pearson Education, Inc. Slide 1 Slide ‹#› Copyright 2019, 2015, 2012, Pearson Education, Inc. If this PowerPoint presentation contains mathematical equations, you may need to check that your computer has the following installed: 1) MathType Plugin 2) Math Player (free versions available) 3) NVDA Reader (free versions available) 1 Chapter Outline 2.1 Frequency Distributions and Their Graphs 2.2 More Graphs and Displays 2.3 Measures of Central Tendency 2.4 Measures of Variation 2.5 Measures of Position Slide ‹#› Copyright 2019, 2015, 2012, Pearson Education, Inc. 2 Section 2.1 Frequency Distributions and Their Graphs Copyright 2019, 2015, 2012, Pearson Education, Inc. Slide ‹#› Slide ‹#› Copyright 2019, 2015, 2012, Pearson Education, Inc. Section 2.1 Objectives How to construct a frequency distribution including limits, midpoints, relative frequencies, cumulative frequencies, and boundaries How to construct frequency histograms, frequency polygons, relative frequency histograms, and ogives Slide ‹#› Copyright 2019, 2015, 2012, Pearson Education, Inc. 4 Frequency Distribution (1 of 3) Frequency Distribution A table that shows classes or intervals of data with a count of the number of entries in each class. The frequency, f, of a class is the number of data entries in the class. Class Frequency, f 1 - 5 5 6 - 10 8 11 - 15 6 16 - 20 8 21 - 25 5 26 - 30 4 Slide ‹#› Copyright 2019, 2015, 2012, Pearson Education, Inc. 5 Frequency Distribution (2 of 3) Each class has a lower class limit, which is the least number that can belong to the class, and an upper class limit, which is the greatest number that can belong to the class. Class Frequency, f 1 - 5 5 6 - 10 8 11 - 15 6 16 - 20 8 21 - 25 5 26 - 30 4 Lower class limits Upper class limits Slide ‹#› Copyright 2019, 2015, 2012, Pearson Education, Inc. 6 Frequency Distribution (3 of 3) The class width is the