2.5 correlation & best fitting lines
- 1. 2.5 Correlation & Best-Fitting Lines Today’s objectives: 1. I will use a scatter plot to identify the correlation shown by a set of data. 2. I will approximate the best- fitting line for a set of data.
- 2. Line of Best Fit Plot the data given in the table as ordered pairs on a coordinate plane. This is a scatter plot. Draw a line that models the data with the same # of points above and below the line. Choose two points on the line and estimate their coordinates. Don’t have to be original data points. Write the equation of the line.
- 3. Type of Correlation Positive Correlation: if the data fits a line with a positive slope, it represents positive correlation. Negative Correlation: if the data fits a line with a negative slope, it represents negative correlation. Relatively No Correlation: if the data doesn’t fit a line with a positive or negative slope, it represents relatively no correlation.
- 4. Correlation Strength: Correlation Coefficient (r) If r >0 but close to 1, there is a strong positive correlation. If r >0 but close to 0, there is a weak positive correlation. If r < 0 but close to -1, there is a strong negative correlation. If r < 0 but close to 0, there is a weak negative correlation.