UCF QMB 3200 Final Exam UPDATED
Questions and CORRECT Answers
Doubling the size of the sample will - CORRECT ANSWER- ✔✔reduce the standard error of
the mean
The sample mean is the point estimator of - CORRECT ANSWER- ✔✔U
A simple random sample of size n from an infinite population of size N is to be selected.
Each possible sample should have - CORRECT ANSWER- ✔✔the same probability of being
selected
Which of the following statements regarding the sampling distribution of sample means is
incorrect? - CORRECT ANSWER- ✔✔The standard deviation of the sampling distribution is
the standard deviation of the population.
A simple random sample of size n from an infinite population is a sample selected such that -
CORRECT ANSWER- ✔✔each element is selected independently and is selected from the
same population
The fact that the sampling distribution of sample means can be approximated by a normal
probability distribution whenever the sample size becomes large is based on the - CORRECT
ANSWER- ✔✔central limit theorem.
Cluster sampling is - CORRECT ANSWER- ✔✔a probability sampling method.
The central limit theorem states that - CORRECT ANSWER- ✔✔if the sample size n is large,
then the sampling distribution of the sample mean can be approximated by a normal
distribution.
The value of the _____ is used to estimate the value of the population parameter - CORRECT
ANSWER- ✔✔sample statistic
,The sampling distribution of is the - CORRECT ANSWER- ✔✔probability distribution of all
possible values of the sample proportion.
Which of the following is not a symbol for a parameter? - CORRECT ANSWER- ✔✔S.
The sample statistic characteristic s is the point estimator of - CORRECT ANSWER- ✔✔σ..
The distribution of values taken by a statistic in all possible samples of the same size from the
same population is called a - CORRECT ANSWER- ✔✔sampling distribution.
Which of the following is a point estimator? - CORRECT ANSWER- ✔✔S.
As a rule of thumb, the sampling distribution of the sample proportion can be approximated
by a normal probability distribution when - CORRECT ANSWER- ✔✔n(1 - p) ≥ 5 and np ≥
5.
A sample of 92 observations is taken from an infinite population. The sampling distribution
of is approximately - CORRECT ANSWER- ✔✔normal because of the central limit theorem.
The central limit theorem is important in Statistics because it enables reasonably accurate
probabilities to be determined for events involving the sample average - CORRECT
ANSWER- ✔✔when the sample size is large regardless of the distribution of the variable.
The distribution of values taken by a statistic in all possible samples of the same size from the
same population is the sampling distribution of - CORRECT ANSWER- ✔✔The sample
Which of these best describes a sampling distribution of a statistic? - CORRECT ANSWER-
✔✔It is the distribution of all of the statistics calculated from all possible samples of the
same sample size.
The probability distribution of all possible values of the sample proportion is the -
CORRECT ANSWER- ✔✔sampling distribution of p.
, For a fixed confidence level and population standard deviation, if we would like to cut our
margin of error in half, we should take a sample size that is - CORRECT ANSWER- ✔✔four
times as large as the original sample size.
We can reduce the margin of error in an interval estimate of p by doing any of the following
except - CORRECT ANSWER- ✔✔increasing the planning value p* to .5.
When computing the sample size needed to estimate a proportion within a given margin of
error for a specific confidence level, what planning value of p should be used when no
estimate of p is available? - CORRECT ANSWER- ✔✔0.50
A statistics teacher started class one day by drawing the names of 10 students out of a hat and
asked them to do as many pushups as they could. The 10 randomly selected students
averaged 15 pushups per person with a standard deviation of 9 pushups. Suppose the
distribution of the population of number of pushups that can be done is approximately
normal. Which of the following statements is true? - CORRECT ANSWER- ✔✔A t
distribution should be used because σ is unknown.
The z value for a 99% confidence interval estimation is - CORRECT ANSWER- ✔✔2.58
In an interval estimation for a proportion of a population, the critical value of z at 99%
confidence is - CORRECT ANSWER- ✔✔2.576.
In interval estimation, as the sample size becomes larger, the interval estimate - CORRECT
ANSWER- ✔✔becomes narrower.In general, higher confidence levels provide larger
confidence intervals.
One way to have high confidence and a small margin of error is to - CORRECT ANSWER-
✔✔increase the sample size.
From a population that is normally distributed, a sample of 30 elements is selected and the
standard deviation of the sample is computed. For the interval estimation of μ, the proper
distribution to use is the - CORRECT ANSWER- ✔✔t distribution with 29 degrees of
freedom.
Questions and CORRECT Answers
Doubling the size of the sample will - CORRECT ANSWER- ✔✔reduce the standard error of
the mean
The sample mean is the point estimator of - CORRECT ANSWER- ✔✔U
A simple random sample of size n from an infinite population of size N is to be selected.
Each possible sample should have - CORRECT ANSWER- ✔✔the same probability of being
selected
Which of the following statements regarding the sampling distribution of sample means is
incorrect? - CORRECT ANSWER- ✔✔The standard deviation of the sampling distribution is
the standard deviation of the population.
A simple random sample of size n from an infinite population is a sample selected such that -
CORRECT ANSWER- ✔✔each element is selected independently and is selected from the
same population
The fact that the sampling distribution of sample means can be approximated by a normal
probability distribution whenever the sample size becomes large is based on the - CORRECT
ANSWER- ✔✔central limit theorem.
Cluster sampling is - CORRECT ANSWER- ✔✔a probability sampling method.
The central limit theorem states that - CORRECT ANSWER- ✔✔if the sample size n is large,
then the sampling distribution of the sample mean can be approximated by a normal
distribution.
The value of the _____ is used to estimate the value of the population parameter - CORRECT
ANSWER- ✔✔sample statistic
,The sampling distribution of is the - CORRECT ANSWER- ✔✔probability distribution of all
possible values of the sample proportion.
Which of the following is not a symbol for a parameter? - CORRECT ANSWER- ✔✔S.
The sample statistic characteristic s is the point estimator of - CORRECT ANSWER- ✔✔σ..
The distribution of values taken by a statistic in all possible samples of the same size from the
same population is called a - CORRECT ANSWER- ✔✔sampling distribution.
Which of the following is a point estimator? - CORRECT ANSWER- ✔✔S.
As a rule of thumb, the sampling distribution of the sample proportion can be approximated
by a normal probability distribution when - CORRECT ANSWER- ✔✔n(1 - p) ≥ 5 and np ≥
5.
A sample of 92 observations is taken from an infinite population. The sampling distribution
of is approximately - CORRECT ANSWER- ✔✔normal because of the central limit theorem.
The central limit theorem is important in Statistics because it enables reasonably accurate
probabilities to be determined for events involving the sample average - CORRECT
ANSWER- ✔✔when the sample size is large regardless of the distribution of the variable.
The distribution of values taken by a statistic in all possible samples of the same size from the
same population is the sampling distribution of - CORRECT ANSWER- ✔✔The sample
Which of these best describes a sampling distribution of a statistic? - CORRECT ANSWER-
✔✔It is the distribution of all of the statistics calculated from all possible samples of the
same sample size.
The probability distribution of all possible values of the sample proportion is the -
CORRECT ANSWER- ✔✔sampling distribution of p.
, For a fixed confidence level and population standard deviation, if we would like to cut our
margin of error in half, we should take a sample size that is - CORRECT ANSWER- ✔✔four
times as large as the original sample size.
We can reduce the margin of error in an interval estimate of p by doing any of the following
except - CORRECT ANSWER- ✔✔increasing the planning value p* to .5.
When computing the sample size needed to estimate a proportion within a given margin of
error for a specific confidence level, what planning value of p should be used when no
estimate of p is available? - CORRECT ANSWER- ✔✔0.50
A statistics teacher started class one day by drawing the names of 10 students out of a hat and
asked them to do as many pushups as they could. The 10 randomly selected students
averaged 15 pushups per person with a standard deviation of 9 pushups. Suppose the
distribution of the population of number of pushups that can be done is approximately
normal. Which of the following statements is true? - CORRECT ANSWER- ✔✔A t
distribution should be used because σ is unknown.
The z value for a 99% confidence interval estimation is - CORRECT ANSWER- ✔✔2.58
In an interval estimation for a proportion of a population, the critical value of z at 99%
confidence is - CORRECT ANSWER- ✔✔2.576.
In interval estimation, as the sample size becomes larger, the interval estimate - CORRECT
ANSWER- ✔✔becomes narrower.In general, higher confidence levels provide larger
confidence intervals.
One way to have high confidence and a small margin of error is to - CORRECT ANSWER-
✔✔increase the sample size.
From a population that is normally distributed, a sample of 30 elements is selected and the
standard deviation of the sample is computed. For the interval estimation of μ, the proper
distribution to use is the - CORRECT ANSWER- ✔✔t distribution with 29 degrees of
freedom.
