UCF QMB 3200 MAKEUP EXAM (MOD
2-5) QUESTIONS & ANSWERS
stratified random sampling - Correct Answers -A form of probability sampling; a random
sampling technique in which the researcher identifies particular demographic categories
of interest and then randomly selects individuals within each category.
Parameter - Correct Answers -A numerical characteristic of a population, such as a
population mean μ, a population standard deviation σ, a population proportion p, and so
on.
Target Population - Correct Answers -The population for which statistical inferences
such as point estimates are made. It is important for the target population to correspond
as closely as possible to the sampled population.
Sampled Population - Correct Answers -The population from which the sample is taken.
Sampling distribution - Correct Answers -A probability distribution consisting of all
possible values of a sample statistic.
sampled statistic - Correct Answers -A sample characteristic, such as a sample mean
x¯, a sample standard deviation s, a sample proportion p¯, and so on.
finite population correction factor - Correct Answers -Definition: The term (N-n)/(N-1)
that is used in the formulas for σx¯ and σp¯ whenever a finite population, rather than an
infinite population, is being sampled. The generally accepted rule of thumb is to ignore
the finite population correction factor whenever n/N≤.05.
simple random sampling - Correct Answers -A simple random sample of size n from a
finite population of size N is a sample selected such that each possible sample of size n
has the same probability of being selected.
standard error - Correct Answers -The standard deviation of a point estimator.
point estimator - Correct Answers -The sample statistic, such as x¯, s, or p¯, that
provides the point estimate of the population parameter.
, Central Limit Theorem - Correct Answers -A theorem that enables one to use the
normal probability distribution to approximate the sampling distribution of x¯ whenever
the sample size is large.
point estimate unbiased - Correct Answers -A property of a point estimator that is
present when the expected value of the point estimator is equal to the population
parameter it estimates.
confidence interval - Correct Answers -Another name for an interval estimate.
margin of error - Correct Answers -The ± value added to and subtracted from a point
estimate in order to develop an interval estimate of a population parameter.
Confidence coefficient - Correct Answers -The confidence level expressed as a decimal
value. For example, .95 is the confidence coefficient for a 95% confidence level.
degrees of freedom - Correct Answers -A parameter of the t distribution. When the t
distribution is used in the computation of an interval estimate of a population mean, the
appropriate t distribution has n − 1 degrees of freedom, where n is the size of the
sample.
confidence level - Correct Answers -The confidence associated with an interval
estimate. For example, if an interval estimation procedure provides intervals such that
95% of the intervals formed using the procedure will include the population parameter,
the interval estimate is said to be constructed at the 95% confidence level.
null hypothesis - Correct Answers -The hypothesis tentatively assumed true in the
hypothesis testing procedure.
two-tailed test - Correct Answers -A hypothesis test in which rejection of the null
hypothesis occurs for values of the test statistic in either tail of its sampling distribution.
alternative hypothesis - Correct Answers -The hypothesis concluded to be true if the null
hypothesis is rejected
p-value - Correct Answers -A probability that provides a measure of the evidence
against the null hypothesis provided by the sample.
Type I error - Correct Answers -The error of rejecting H0 when it is true.
level of significance - Correct Answers -The probability of making a Type I error when
the null hypothesis is true as an equality.
Type II error - Correct Answers -Definition: The error of accepting H0 when it is false.
2-5) QUESTIONS & ANSWERS
stratified random sampling - Correct Answers -A form of probability sampling; a random
sampling technique in which the researcher identifies particular demographic categories
of interest and then randomly selects individuals within each category.
Parameter - Correct Answers -A numerical characteristic of a population, such as a
population mean μ, a population standard deviation σ, a population proportion p, and so
on.
Target Population - Correct Answers -The population for which statistical inferences
such as point estimates are made. It is important for the target population to correspond
as closely as possible to the sampled population.
Sampled Population - Correct Answers -The population from which the sample is taken.
Sampling distribution - Correct Answers -A probability distribution consisting of all
possible values of a sample statistic.
sampled statistic - Correct Answers -A sample characteristic, such as a sample mean
x¯, a sample standard deviation s, a sample proportion p¯, and so on.
finite population correction factor - Correct Answers -Definition: The term (N-n)/(N-1)
that is used in the formulas for σx¯ and σp¯ whenever a finite population, rather than an
infinite population, is being sampled. The generally accepted rule of thumb is to ignore
the finite population correction factor whenever n/N≤.05.
simple random sampling - Correct Answers -A simple random sample of size n from a
finite population of size N is a sample selected such that each possible sample of size n
has the same probability of being selected.
standard error - Correct Answers -The standard deviation of a point estimator.
point estimator - Correct Answers -The sample statistic, such as x¯, s, or p¯, that
provides the point estimate of the population parameter.
, Central Limit Theorem - Correct Answers -A theorem that enables one to use the
normal probability distribution to approximate the sampling distribution of x¯ whenever
the sample size is large.
point estimate unbiased - Correct Answers -A property of a point estimator that is
present when the expected value of the point estimator is equal to the population
parameter it estimates.
confidence interval - Correct Answers -Another name for an interval estimate.
margin of error - Correct Answers -The ± value added to and subtracted from a point
estimate in order to develop an interval estimate of a population parameter.
Confidence coefficient - Correct Answers -The confidence level expressed as a decimal
value. For example, .95 is the confidence coefficient for a 95% confidence level.
degrees of freedom - Correct Answers -A parameter of the t distribution. When the t
distribution is used in the computation of an interval estimate of a population mean, the
appropriate t distribution has n − 1 degrees of freedom, where n is the size of the
sample.
confidence level - Correct Answers -The confidence associated with an interval
estimate. For example, if an interval estimation procedure provides intervals such that
95% of the intervals formed using the procedure will include the population parameter,
the interval estimate is said to be constructed at the 95% confidence level.
null hypothesis - Correct Answers -The hypothesis tentatively assumed true in the
hypothesis testing procedure.
two-tailed test - Correct Answers -A hypothesis test in which rejection of the null
hypothesis occurs for values of the test statistic in either tail of its sampling distribution.
alternative hypothesis - Correct Answers -The hypothesis concluded to be true if the null
hypothesis is rejected
p-value - Correct Answers -A probability that provides a measure of the evidence
against the null hypothesis provided by the sample.
Type I error - Correct Answers -The error of rejecting H0 when it is true.
level of significance - Correct Answers -The probability of making a Type I error when
the null hypothesis is true as an equality.
Type II error - Correct Answers -Definition: The error of accepting H0 when it is false.
