The table gives 6 paired observations of x = advertising spend in k€ and y = sales in k€. Use the least-squares line ŷ = a + b·x. Find the intercept a.
Linear regression & correlation worksheet with answers
1.Easy
n = 6
a =
2.Easy
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 intercept a.
n = 6
a =
3.Medium
The table gives 5 paired observations of x = car age in years and y = price in k€. Find Pearson's correlation coefficient r.
n = 5
r =
4.Medium
The table gives 6 paired observations of x = temperature in °C and y = ice creams sold. Find Pearson's correlation coefficient r.
n = 6
r =
5.Hard
The table gives 5 paired observations of x = hours studied and y = exam score. Use the least-squares line ŷ = a + b·x. Predict ŷ for x = 4.
n = 5x = 4
ŷ =
6.Hard
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. Predict ŷ for x = 3.
n = 5x = 3
ŷ =
Answer key
- 1. a = 40.15
- 2. a = 25
- 3. r = −0.9333
- 4. r = 0.9263
- 5. ŷ = 65.6
- 6. ŷ = 8.6
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