Construct a 95% confidence interval to estimate the population
proportion with a sample proportion equal to
0.45 and a sample size equal to 120.
----- A 95% confidence interval estimates that the population
proportion is between a lower limit of
___ and an upper limit of ___
????
1 - A 95% confidence interval for a population
proportion was constructed using a sample proportion from a random
sample. Which of the following statements are correct? Select all
that apply.
A) We don't know if the 95% confidence interval actually does or
doesn't contain the population proportion.
B) The population proportion must lie in the 95% confidence
interval.
C) There is a 95% chance that the 95% confidence interval
actually contains the population proportion.
D) The sample proportion must...
We wish to create a 95% confidence interval for the proportion.
A sample of 50 gives a proportion of 0.2. Find the
upper value for the confidence interval. Round to
3 decimal places.
At a confidence level of 95% a confidence interval for a
population proportion is determined to be 0.65 to 0.75. If the
sample size had been larger and the estimate of the population
proportion the same, this 95% confidence interval estimate as
compared to the first interval estimate would be
A. the same
B. narrower
C. wider
Calculate a 95 percent confidence interval for the proportion of
interest. Make sure you check all conditions. (high interval) 0.397
and (low interval) 0.257 How do you do the success-failure
condition for number 5? (when checking to see if all conditions are
met).
QUESTION 10
What is the 95% confidence interval for the proportion of
smokers in the population (to 4 decimals)?
QUESTION 8
Question 8-10 are based on the following
information:
The Centers for Disease Control reported the percentage
of people 18 years of age and older who smoke (CDC website,
December 14, 2014). Suppose that a study designed to collect new
data on smokers and nonsmokers uses a preliminary estimate of the
proportion who smoke of .35.
How large a sample...
A smart phone manufacturer is interested in constructing a 95%
confidence interval for the proportion of smart phones that break
before the warranty expires. 80 of the 1669 randomly selected smart
phones broke before the warranty expired. Round answers to 4
decimal places where possible. a. With 95% confidence the
proportion of all smart phones that break before the warranty
expires is between and . b. If many groups of 1669 randomly
selected smart phones are selected, then a different...
A psychologist is interested in constructing a 95% confidence
interval for the proportion of people who accept the theory that a
person's spirit is no more than the complicated network of neurons
in the brain. 71 of the 811 randomly selected people who were
surveyed agreed with this theory. Round answers to 4 decimal places
where possible.
a. With 95% confidence the proportion of all people who accept
the theory that a person's spirit is no more than the complicated...
A newsgroup is interested in constructing a 95% confidence
interval for the proportion of all Americans who are in favor of a
new Green initiative. Of the 537 randomly selected Americans
surveyed, 368 were in favor of the initiative. a. With 95%
confidence the proportion of all Americans who favor the new Green
initiative is between and . b. If many groups of 537 randomly
selected Americans were surveyed, then a different confidence
interval would be produced from each group....
A smart phone manufacturer is interested in constructing a 95%
confidence interval for the proportion of smart phones that break
before the warranty expires. 92 of the 1695 randomly selected smart
phones broke before the warranty expired. Round answers to 4
decimal places where possible.
a. With 95% confidence the proportion of all smart phones that
break before the warranty expires is between and .
b. If many groups of 1695 randomly selected smart phones are
selected, then a different confidence...