1. Unit 3 Sections 10-1 & 10-2

2. What we will be able to do throughout this chapter…  Determine relationships between two or more variables  Determine strengths of relationships  Determine what types of relationships exist  Determine what kind of predictions can be made from the relationship Section 10-1

3.  Correlation – statistical measure used to determine whether a relationship between variables exists.  Regression – statistical measure used to describe the nature of the relationship between two variables.  Positive vs. Negative  Linear vs. Nonlinear Section 10-1

4. 10-2: Scatter Plots  Scatter plot – a graph of the ordered pairs (x, y) of numbers consisting of the independent variable x and the dependent variable y.  The independent variable is plotted on the horizontal axis.  The dependent variable is plotted on the vertical axis.  The scatter plot is a visual method for showing the relationship between the independent and dependent variables.

5. Constructing a Scatter Plot Section 10-2  Construct a scatter plot for the data obtained in a study of age and systolic blood pressure of six randomly selected subjects. SubjectAge (x)Pressure (y) A43128 B48120 C56135 D61143 E67141 F70152

6. Constructing a Scatter Plot Section 10-2  Construct a scatter plot for the data obtained in a study of the number of absences and the final grades of seven randomly selected students from a statistics class. Subject# of Absences (x)Final Grade (y) A682 B286 C1543 D974 E1258 F590 G878

7. Constructing a Scatter Plot Section 10-2  Construct a scatter plot for the data obtained in a study on the number of hours that nine people exercise each week and the amount of milk (in ounces) each person consumes per week. SubjectHours (x)Amount (y) A348 B08 C232 D564 E810 F532 G1056 H272 I148

8. Relationships  Example 1 – shows a positive relationship since as a person’s age increases their blood pressure tends to increase also.  Example 2 – shows a negative relationship since as the number of absences increases the final grade decreases.  Example 3 – shows no relationship since no pattern is discernable. Section 10-2

9. Homework:  Read and take notes on Section 10.3 (pg 533-541)  Pg 541: #1-6, 8, 9, 11  Pg 543: #15