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Student Response
Sample response:
1. The sign of the correlation coe cient matches the sign of the slope for the best t line. The closer the correlation coe cient value is to 0, the worse t for the best t line. The closer the correlation coe cient is to 1 or -1, the better the best t line ts the data.
2.
Student Lesson Summary
While residuals can help pick the best line to t the data among all lines, we still need a way to determine the strength of a linear relationship. Scatter plots of data that are close to the best t line are better modeled by the line than scatter plots of data that are farther from the line.
The correlation coe cient is a convenient number that can be used to describe the strength and direction of a linear relationship. Usually represented by the letter , the correlation coe cient can take values from -1 to 1. The sign of the correlation coe cient is the same as the sign of the slope for the best t line. The closer the correlation coe cient is to 0, the weaker the linear relationship. When the correlation coe cient is closer to 1 or -1, the linear model ts the data better.
since the data appears to be decreasing and a line is an okay t for the data, but not
perfect.
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Algebra