Statistics Exam 3 with Complete Solutions
Question : a
CORRECT ANSWER : The symbol for level of significance
(probability of a type I error).
Question : Alternative hypothesis
CORRECT ANSWER : The hypothesis that the researcher
wants to prove or verify; a statement about the value of a parameter that is either "less than," "greater than," "not equal to."
Question : B
CORRECT ANSWER : The probability of failing to reject a
false null hypothesis (probability of a type II error).
Question : Conditions
CORRECT ANSWER : The basic premises for inferential
procedures. If the conditions are not met, the results may not be valid.
Question : Confidence Interval
CORRECT ANSWER : An estimate of the value of a
parameter in interval form with an associated level of confidence; in other words, a list of reasonable or plausible values for the parameter based on the value of a statistic.
Question : Confidence level
CORRECT ANSWER : The percent of the time that the
confidence interval estimation procedure will give you intervals containing the value of the parameter being estimated.
Question : Degrees of freedom
CORRECT ANSWER : A characteristic of the t-distribution
(e.g. n - 1 for a one-sample t); a measure of the amount of information available for estimating σ using s.
Question : Fail to Reject Ho
CORRECT ANSWER : The appropriate statistical
conclusion when the P- value is greater than α.
Question : Hypothesis testing (Test of Significance)
CORRECT ANSWER : assessing evidence provided by the
data in favor of or against some claim about the population
Question : Inference
CORRECT ANSWER : Using results about sample statistics
to draw conclusions about population parameters.
Question : Interval estimation
CORRECT ANSWER : estimate an unknown parameter
using an interval of values that is likely to contain the true value of that parameter
Question : Level of significance (symbolized by α)
CORRECT ANSWER : The probability of rejecting a true
null hypothesis; equivalently, the largest risk a researcher is willing to take of rejecting a true null hypothesis.
Question : Margin of error for 95% confidence
CORRECT ANSWER : The maximum amount that a
statistic value will differ from the parameter value for the middle 95% of the distribution of all possible statistics.
Question : Matched pairs
CORRECT ANSWER : Either two measurements are taken
on each individual such as pre and post OR two individuals are matched by a third variable (different from the explanatory variable and the response variable) such as identical twins.
Question : Matched pairs t test
CORRECT ANSWER : The hypothesis testing method for
matched pairs data. The typical null hypothesis is H0:μd = 0
where μd is the mean difference between treatments. For this test, a difference is computed within every pair. The mean and standard deviation of these differences are computed and used in computing the test statistics.