MGSC291 Test 2
True or False: Given a right tailed hypothesis test, if the value of this test statistic is 1.82 and the critical value is 1.645, then we fail to reject the null hypothesis.
False
we do not reject the null hypothesis when the p-value is
_> a
when examining the possible outcome of an election, what type of confidence interval is most suitable for estimating the current support for a candidate?
confidence interval for the population proportion
each t distribution is identified by its
degrees of freedom
whenever we construct a confidence interval for the population mean, the margin of error includes the standard error of x(bar) and the
desired level of confidence
when estimating a population mean, the t(df) distribution is used when the
population variance is unknown
The mean and standard deviation are often used to describe ____ data, while the proportion is a descriptive measure that can also be used for ____ data.
quantitative, qualitative
when the population standard deviation is unknown the standard error for the sample mean is calculated as
s / √n
the critical value of a hypothesis test is
separates the rejection region from the non-rejection region
Which of the following is necessary for creating confidence intervals for the population mean?
Normality of the estimator
suppose you are constructing a confidence interval for the population mean. For a given sample size and population standard deviation, how will the width of the interval change as the confidence level increases?
it gets larger
in order to derive a confidence interval for m, the estimator x(bar) must have a
normal sampling distribution
A two tailed test of the population mean is conducted at a=.10. The calculated test statistic is z=1.55 and P(z>1.55)=0.0606. The null hypothesis should ____.
not be rejected bc the p-value = 0.1212 > 0.10
which of the following is a descriptive measure for a qualitative variable? Proportion Median Standard Deviation Mean
Proportion
True or False: A confidence interval provides a range of values that should contain a population parameter with a certain level of confidence
True
A 95% confidence interval for the population mean implies that
for repeated samples, 95% of the sample means with fall within the interval
the most practical way to reduce the margin of error is
increase the sample size
Suppose you and constructing a confidence interval for the population mean. for a given confidence level and sample size, the width of the interval is wider for
larger standard deviation
when constructing a confidence interval for the population mean, the factors that affect the width of the confidence interval for a given standard deviation are
the confidence level and the sample size
Suppose you and constructing a confidence interval for the population mean. For a given sample size and standard deviation, the width of the confidence interval is ____ for a greater confidence level
wider