In: Statistics and Probability
Q2. A company wishes to survey how the customer satisfaction
rate for auto-insurance
companies in a state has changed over the years. In 2018, the
company randomly selected
200 car-owners from that state and 162 of them mentioned that they
are satisfied with
their auto-insurance providers. In 2019, the company randomly
selected 188 car-owners
from that state and 145 of them mentioned satisfaction with
auto-insurance. Based on this
data, answer the following questions. [4+3 = 7 points]
(a) Suppose, the company wants to test the claim that the customer
satisfaction rate was
different in these two years. Write the ToH in the context of the
problem and, using the CR
method, conclude at 5% level.
(b) Suppose, the company wants to test the claim that the customer
satisfaction rate has
reduced in 2019 relative to 2018, in that state. Write the ToH in
the context of the problem
and, using the p-value method, conclude at 5% level.