STAT 211 EXAM ALL QUESTIONS AND 100%
CORRECT ANSWERS!!
Which of these statements correctly interprets what it means to be "95% confident"?
A. 95% of the sample is in the confidence interval.
B. 95% of samples will produce a confidence interval that captures the true proportion.
C. 95% of the time, the sample proportion will be in the interval.
B. 95% of samples will produce a confidence interval that captures the true proportion.
A research company polled a random sample of
646 teens about Internet use 50% of those teens reported that they had misrepresented
their age online to gain access to websites and online services.
Explain the meaning of p^=0.50 in the context of this situation.
A. The meaning of p=0.50 is that the researchers have 95% confidence that 50% of all U.S.
teens would say that they have misrepresented their age online.
B. The meaning of p=0.50 is that the researchers have 95% confidence that 50% of the 646
teens in the sample said they have misrepresented their age online.
C. The meaning of p=0.50 is that 50% of the 646 teens in the sample said they have
misrepresented their age online. This is the researchers' best estimate of p, the proportion
of all U.S. teens who would say they have done so.
D. The meaning of p=0.50 is that 50% of the 646 teens in the sample said they have
misrepresented their age online. This is the researchers' best estimate of p, the proportion
of the 646
teens in the sample who said they had done so.
C. The meaning of p=0.50 is that 50% of the 646 teens in the sample said they have
misrepresented their age online. This is the researchers' best estimate of p, the proportion of all
U.S. teens who would say they have done so.
A research company polled a random sample of
646 teens about Internet use 50% of those teens reported that they had misrepresented
their age online to gain access to websites and online services. SE (P^) = .020 Explain what
this standard error means in the context of this situation.
, A. The standard error is the best estimate of the margin of error of the poll. The
researchers can be confident that the difference between p and p is not greater than the
standard error.
B. The standard error is the best estimate of the standard deviation of the sampling
distribution of the proportions, which measures the amount of variation in the sample and
population proportions.
C. The standard error is the best estimate of the standard deviation of the sampling
distribution of the proportions, which measures the amount of variation in the sample
proportion expected to be seen from sample to sample when 646 teens are asked the polling
question.
D. The standard error is the best estimate of the margin of error of the poll, which
measures the amount of variation in the sample size expected to be seen from sample to
sample when 646 teens are asked the polling question.
C. The standard error is the best estimate of the standard deviation of the sampling distribution of
the proportions, which measures the amount of variation in the sample proportion expected to be
seen from sample to sample when 646 teens are asked the polling question.
Reaching out 2 standard errors on either side of the sample proportion makes us
__________ confident that the true proportion is captured within the interval.
95%
Of 575 broiler chickens purchased from various kinds of food stores in different regions of
a country and tested for types of bacteria that cause food-borne illnesses, 36% were
infected with a particular bacterium. 95% CI = 32.1% - 39.9% What does the confidence
interval say about chicken sold in the country?
A. There is a 95% chance that the true proportion of broiler chickens infected with the
bacterium is in the interval.
B. In 95% of samples of broiler chickens sold in the country, the proportion infected with
the bacterium will be in the interval.
C. We are 95% confident that the interval captures the true proportion of all broiler
chickens sold in the country that are infected with the bacterium.
CORRECT ANSWERS!!
Which of these statements correctly interprets what it means to be "95% confident"?
A. 95% of the sample is in the confidence interval.
B. 95% of samples will produce a confidence interval that captures the true proportion.
C. 95% of the time, the sample proportion will be in the interval.
B. 95% of samples will produce a confidence interval that captures the true proportion.
A research company polled a random sample of
646 teens about Internet use 50% of those teens reported that they had misrepresented
their age online to gain access to websites and online services.
Explain the meaning of p^=0.50 in the context of this situation.
A. The meaning of p=0.50 is that the researchers have 95% confidence that 50% of all U.S.
teens would say that they have misrepresented their age online.
B. The meaning of p=0.50 is that the researchers have 95% confidence that 50% of the 646
teens in the sample said they have misrepresented their age online.
C. The meaning of p=0.50 is that 50% of the 646 teens in the sample said they have
misrepresented their age online. This is the researchers' best estimate of p, the proportion
of all U.S. teens who would say they have done so.
D. The meaning of p=0.50 is that 50% of the 646 teens in the sample said they have
misrepresented their age online. This is the researchers' best estimate of p, the proportion
of the 646
teens in the sample who said they had done so.
C. The meaning of p=0.50 is that 50% of the 646 teens in the sample said they have
misrepresented their age online. This is the researchers' best estimate of p, the proportion of all
U.S. teens who would say they have done so.
A research company polled a random sample of
646 teens about Internet use 50% of those teens reported that they had misrepresented
their age online to gain access to websites and online services. SE (P^) = .020 Explain what
this standard error means in the context of this situation.
, A. The standard error is the best estimate of the margin of error of the poll. The
researchers can be confident that the difference between p and p is not greater than the
standard error.
B. The standard error is the best estimate of the standard deviation of the sampling
distribution of the proportions, which measures the amount of variation in the sample and
population proportions.
C. The standard error is the best estimate of the standard deviation of the sampling
distribution of the proportions, which measures the amount of variation in the sample
proportion expected to be seen from sample to sample when 646 teens are asked the polling
question.
D. The standard error is the best estimate of the margin of error of the poll, which
measures the amount of variation in the sample size expected to be seen from sample to
sample when 646 teens are asked the polling question.
C. The standard error is the best estimate of the standard deviation of the sampling distribution of
the proportions, which measures the amount of variation in the sample proportion expected to be
seen from sample to sample when 646 teens are asked the polling question.
Reaching out 2 standard errors on either side of the sample proportion makes us
__________ confident that the true proportion is captured within the interval.
95%
Of 575 broiler chickens purchased from various kinds of food stores in different regions of
a country and tested for types of bacteria that cause food-borne illnesses, 36% were
infected with a particular bacterium. 95% CI = 32.1% - 39.9% What does the confidence
interval say about chicken sold in the country?
A. There is a 95% chance that the true proportion of broiler chickens infected with the
bacterium is in the interval.
B. In 95% of samples of broiler chickens sold in the country, the proportion infected with
the bacterium will be in the interval.
C. We are 95% confident that the interval captures the true proportion of all broiler
chickens sold in the country that are infected with the bacterium.
