The table gives 5 paired observations of x = hours studied and y = exam score. Use the least-squares line ŷ = a + b·x. Find the intercept a.
Linear regression & correlation worksheet with answers
The table gives 6 paired observations of x = car age in years and y = price in k€. Use the least-squares line ŷ = a + b·x. Find the slope b.
The table gives 6 paired observations of x = car age in years and y = price in k€. Find the coefficient of determination r² of the least-squares line.
The table gives 6 paired observations of x = advertising spend in k€ and y = sales in k€. Find Pearson's correlation coefficient r.
The table gives 6 paired observations of x = temperature in °C and y = ice creams sold. Use the least-squares line ŷ = a + b·x. A new observation (23, 111) is made. Find its residual e = y − ŷ.
The table gives 5 paired observations of x = load in kN and y = extension in mm. Use the least-squares line ŷ = a + b·x. For which value x does the line predict ŷ = 34?
Answer key
- 1. a = 41.5
- 2. b = −2.171
- 3. r² = 0.9846
- 4. r = 0.9903
- 5. e = −3.267
- 6. x = 8.973
Full step-by-step solutions: practise this topic on examproblems.com.