The table gives 5 paired observations of x = temperature in °C and y = ice creams sold. Use the least-squares line ŷ = a + b·x. Find the intercept a.
Linear regression & correlation worksheet with answers
1.Easy
n = 5
a =
2.Easy
The table gives 6 paired observations of x = hours studied and y = exam score. Use the least-squares line ŷ = a + b·x. Find the slope b.
n = 6
b =
3.Medium
The table gives 6 paired observations of x = hours studied and y = exam score. Find Pearson's correlation coefficient r.
n = 6
r =
4.Medium
The table gives 6 paired observations of x = advertising spend in k€ and y = sales in k€. Find Pearson's correlation coefficient r.
n = 6
r =
5.Hard
The table gives 6 paired observations of x = hours studied and y = exam score. Use the least-squares line ŷ = a + b·x. Predict ŷ for x = 4.5.
n = 6x = 4.5
ŷ =
6.Hard
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. Predict ŷ for x = 1.5.
n = 6x = 1.5
ŷ =
Answer key
- 1. a = −5.6
- 2. b = 3.086
- 3. r = 0.9884
- 4. r = 0.9724
- 5. ŷ = 64.17
- 6. ŷ = 26.91
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