Chapter 9.1（课件）- 《统计学基础（英文版）》同步教学（人民大学版）

Chapter Correlation and Regression 9 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. 1 Larson/Farber 6th ed Chapter 1 Chapter Outline 9.1 Correlation 9.2 Linear Regression 9.3 Measures of Regression and Prediction Intervals 9.4 Multiple Regression . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Section 9.1 Correlation . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Section 9.1 Objectives An introduction to linear correlation, independent and dependent variables, and the types of correlation How to find a correlation coefficient How to test a population correlation coefficient ρ using a table How to perform a hypothesis test for a population correlation coefficient ρ How to distinguish between correlation and causation . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Correlation Correlation A relationship between two variables. The data can be represented by ordered pairs (x, y) x is the independent (or explanatory) variable y is the dependent (or response) variable . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Correlation In a scatter plot, the ordered pairs (x, y) are graphed as points in a coordinate plane. The independent (explanatory) variable x is measured on the horizontal axis, and the dependent (response) variable y is measured on the vertical axis. A scatter plot can be used to determine whether a linear (straight line) correlation exists between two variables. . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Correlation . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Example: Constructing a Scatter Plot An economist wants to determine whether there is a linear relationship between a country’s gross domestic product (GDP) and carbon dioxide (CO2) emissions. The data are shown in the table. Display the data in a scatter plot and describe the type of correlation. (Source: World Bank and U.S. Energy Information Administration) . 1 Copyright 2019, 2015, 2012, Pearson Education, Inc. Solution: Const