UCF QMB 3200 FINAL EXAM WITH COMPLETE 150 QUESTIONS AND CORRECT ANSWERS

UCF QMB 3200 FINAL EXAM WITH COMPLETE 150
QUESTIONS AND CORRECT ANSWERS

QUESTION: A simple random sample of size n from an infinite population is a sample selected such that -
ANSWER-each element is selected independently and is selected from the same population



QUESTION: 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 - ANSWER-central limit
theorem.



QUESTION: Cluster sampling is - ANSWER-a probability sampling method.



QUESTION: The central limit theorem states that - ANSWER-if the sample size n is large, then the
sampling distribution of the sample mean can be approximated by a normal distribution.

Doubling the size of the sample will - ANSWER-reduce the standard error of the mean



QUESTION: The sample mean is the point estimator of - ANSWER-U



QUESTION: A simple random sample of size n from an infinite population of size N is to be selected. Each
possible sample should have - ANSWER-the same probability of being selected



QUESTION: Which of the following statements regarding the sampling distribution of sample means is
incorrect? - ANSWER-The standard deviation of the sampling distribution is the standard deviation of
the population.



QUESTION: The value of the _____ is used to estimate the value of the population parameter - ANSWER-
sample statistic

,QUESTION: The sampling distribution of is the - ANSWER-probability distribution of all possible values of
the sample proportion.



QUESTION: Which of the following is not a symbol for a parameter? - ANSWER-S.



QUESTION: The sample statistic characteristic s is the point estimator of - ANSWER-σ..



QUESTION: The distribution of values taken by a statistic in all possible samples of the same size from
the same population is called a - ANSWER-sampling distribution.



QUESTION: Which of the following is a point estimator? - ANSWER-S.



QUESTION: As a rule of thumb, the sampling distribution of the sample proportion can be approximated
by a normal probability distribution when - ANSWER-n(1 - p) ≥ 5 and np ≥ 5.



QUESTION: A sample of 92 observations is taken from an infinite population. The sampling distribution
of is approximately - ANSWER-normal because of the central limit theorem.



QUESTION: The central limit theorem is important in Statistics because it enables reasonably accurate
probabilities to be determined for events involving the sample average - ANSWER-when the sample size
is large regardless of the distribution of the variable.



QUESTION: 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 - ANSWER-The sample



QUESTION: Which of these best describes a sampling distribution of a statistic? - ANSWER-It is the
distribution of all of the statistics calculated from all possible samples of the same sample size.

, QUESTION: The probability distribution of all possible values of the sample proportion is the - ANSWER-
sampling distribution of p.



QUESTION: 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 - ANSWER-four times as large as the original
sample size.



QUESTION: We can reduce the margin of error in an interval estimate of p by doing any of the following
except - ANSWER-increasing the planning value p* to .5.



QUESTION: 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? - ANSWER-0.50



QUESTION: 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? - ANSWER-A t distribution should be used because σ is unknown.



QUESTION: The z value for a 99% confidence interval estimation is - ANSWER-2.58



QUESTION: In an interval estimation for a proportion of a population, the critical value of z at 99%
confidence is - ANSWER-2.576.



QUESTION: In interval estimation, as the sample size becomes larger, the interval estimate - ANSWER-
becomes narrower.In general, higher confidence levels provide larger confidence intervals.



QUESTION: One way to have high confidence and a small margin of error is to - ANSWER-increase the
sample size.