Question

Sparrowhawk colonies. One of nature’s patterns connects the percent of adult birds in a

colony that return from the previous year and the number of new adults that join the colony. It

is expected that the percent return of adult birds from the previous year can be used to predict

how many new adult birds will join a colony. The data set sparrowhawk.xlsx contains

information for 13 colonies of sparrowhawks. The variables are the percent of adult birds in a

colony that return from the previous year (Percent return) and the number of new adults that

join the colony (New adults).

(a) Using an appropriate graphical display and the summary statistics, describe the distribution

of the percent of adult birds in a colony that return from the previous year (Percent return).

(b) Using an appropriate graphical format, display AND describe the relationship between the

percent of adult birds in a colony that return from the previous year (Percent return) and

the number of new adults that join the colony (New adults).

(c) Find the sample correlation coefficient between the percent of adult birds in a colony that

return from the previous year (Percent return) and the number of new adults that join the

colony (New adults). Comment.

(d) Fit a least-squares line to the data. Write down the equation of the fitted line (model) and

interpret all parameters in the model

(e) Predict how many new adult birds will join the colony, when 30% and 70% of the adults

from the previous year return respectively

Percent return (%)	New adults
74	5
66	6
81	8
52	11
73	12
62	15
52	16
45	17
62	18
46	18
60	19
46	20
38	20

Answer 1