A medical researcher wishes to determine how the dosage (in mg) of a drug affects the heart rate of the patient. DosageHeart rate Find the correlation coefficient & interpret it. 2.Find & interpret the slope. 3.Find & interpret the y-intercept. 4.Give the least squares regression line.
A medical researcher wishes to determine how the dosage (in mg) of a drug affects the heart rate of the patient. DosageHeart rate
RESIDUALS Section 3.2B
Residuals
DosageHeart rate Find the predicted value for a dosage of 0.4 mg. 2.Find the residual for (0.4, 80).
DosageHeart rate * The sum of the residuals is always zero!
Residual Plot It is a scatterplot of the residuals vs the explanatory variable. They help us to assess how well a regression line fits the data. The residual plot should show no obvious pattern The residuals should be relatively small.
DosageHeart rate * The sum of the residuals is always zero!
Residual Plot
Height vs Shoe size – residual plot Good residual plot – show relatively no pattern.
Good or Bad
Standard Deviation of the Residuals
DosageHeart rate
Homework *Page 191 (43, 45, 55, 60, 62)