In: Statistics and Probability
The health department of a large city has developed an
air pollution index
that measures the level of several air pollutants that cause
respiratory
distress in humans. The following table gives the pollution index
(on
a scale of 1 to 10, with 10 being the worst) for 7 randomly
selected
summer days and the number of patients with acute respiratory
problems
admitted to the emergency rooms of the city’s hospitals.
Air pollution index 4.5 6.7 8.2 5.0 4.6 6.1 3.0
Emergency admissions 53 82 102 60 39 42 27
Taking the air pollution index as an independent variable x and the
num-
ber of emergency admissions as a dependent variable y, we assume
a
probabilistic linear regression model given by
y = a + bx + ε.
(a) (3 points) Compute the least squares estimates ˆa and ˆb for a
and b,
respectively.
(b) (2 points) Compute SSE, i.e., the minimum achieved sum of
squares
of errors.