In: Statistics and Probability
Below are the average heights for American boys in 1990.
Age (years) | Height (cm) |
---|---|
birth | 50.8 |
2 | 83.8 |
3 | 91.4 |
5 | 106.6 |
7 | 119.3 |
10 | 137.1 |
14 | 157.5 |
d) Calculate the least squares line. Put the equation in the form of: ŷ = a + bx. (Round your answers to three decimal places.)
ŷ =____+____x
e) Find the correlation coefficient r. (Round your answer to four decimal places.)
r =_____
f) Find the estimated average height for a one-year-old. (Use your equation from part (d). Round your answer to one decimal place.)
_____cm
Find the estimated average height for a eleven-year-old. (Use your
equation from part (d). Round your answer to two decimal
places.)
_____cm
i) Use the least squares line to estimate the average height for a fifty-four-year-old man. (Use your equation from part (d). Round your answer to one decimal place.)
_____cm
f) What is the slope of the least squares (best-fit) line? (Round your answer to three decimal places.)
_____
Interpret the slope. (Round your answer to three decimal
places.)
As age increases by one year, the average height _____ by _____ centimeters.