Busn ch 9
Of the two types of statistical errors, the one that decision makers have most control over is Type I error.
True
The following is an appropriate statement of the null and alternate hypotheses for a test of a population mean: H0 : μ = 45 HA : μ < 50
True
) A local medical center has advertised that the mean wait for services will be less than 15 minutes. In an effort to test whether this claim can be substantiated, a random sample of 100 customers was selected and their wait times were recorded. The mean wait time was 17.0 minutes. Based on this sample result, there is sufficient evidence to reject the medical center's claim.
False
) If the sample data lead the decision maker to reject the null hypothesis, the alpha level is the maximum probability of committing a Type II error.
False
2) In hypothesis testing, the null hypothesis is the hypothesis that the researcher believes is true and
False
A conclusion to "not reject" the null hypothesis is the same as the decision to "accept the null hypothesis".
False
If a hypothesis test leads to incorrectly rejecting the null hypothesis, a Type II statistical error has been made.
False
The null and alternate hypotheses must be opposites of each other.
True
Whenever possible, in establishing the null and alternative hypotheses, the research hypothesis should be made the alternative hypothesis.
True
local medical center has advertised that the mean wait for services will be less than 15 minutes. Given this claim, the hypothesis test for the population mean should be a one-tailed test with the rejection region in the lower (left-hand) tail of the sampling distribution.
True
A report recently submitted to the managing partner for a market research company stated "the hypothesis test may have resulted in either a Type I or a Type II error. We won't know which one occurred until later." This statement is one that we might correctly make for any hypothesis that we have conducted.
False
Hypothesis testing and confidence interval estimation are essentially two totally different statistical procedures and share little in common with each other.
False
In a hypothesis test, the p-value measures the probability that the alternative hypothesis is true
False
In a one-tailed hypothesis test, the larger the significance level, the greater the critical value will be.
False
When using the t-distribution in a hypothesis test, the population does not need to be assumed normally distributed.
False
) The significance level in a hypothesis test corresponds to the maximum probability that a Type I error will be committed.
True
14) In a two-tailed hypothesis test the area of both tails in the rejection region is equal to α.
True
In conducting a hypothesis test where the conclusion is to reject the null hypothesis, then either a correct decision has been made or else a Type I error.
True
In testing a hypothesis, statements for the null and alternative hypotheses as well as the selection of the level of significance should precede the collection and examination of the data.
True
When the decision maker has control over the null and alternative hypotheses, the alternative hypotheses should be the "research" hypothesis.
True