Records on a fleet of trucks reveal that the average life of a set of spark plugs is
normally distributed with a mean of 22,100 miles. The fleet owner purchased 18 sets
and found that the sample average life was 23,400 miles; the sample standard deviation
was 1,412 miles. What is the test statistic?
A survey of property owners’ opinions about a street-widening project was taken to
determine if owners’ opinions were related to the distance between their home and the
street. A randomly selected sample of 100 property owners was contacted and the
results are shown next.
What is the alternative hypothesis?
In a graph of the uniform distribution, probabilities are represented by ___________.
The null hypothesis in the goodness-of-fit test is __________.
Provide two examples when a paired t-test can be used to test a hypothesis of no
difference between population means.
Six people have declared their intentions to run for a seat on the school board in the
next local election. A poll is conducted during the campaign among 1,020 randomly
sampled voters to determine if there is any clear preference among the voters. The
responses are shown next.
What is the alternative hypothesis?
The shape of the chi-square distribution is _________________.
Chebyshev’s Theorem is valid for any ________.
A machine cuts steel to length for nails. The mean length of a nail is 43 millimeters.
There is concern that the settings of the machine producing the nails have changed. To
test the claim, 12 nails (n = 12) were sampled. The mean of the sample is 41.5 and the
standard deviation is 1.784. To test the claim at the 0.02 significance level, what is the
critical value?
We are interested in knowing if the following frequency distribution is normally
distributed. The population mean and standard deviation are 600 and 160, respectively.
To test the hypothesis that the frequency distribution is normally distributed, what are
the degrees of freedom for the chi-square statistic?
The “lowest” level of measurement is ___________.
In multiple regression, the ________ is used to test the global hypothesis.
A survey of property owners’ opinions about a street-widening project was taken to
determine if owners’ opinions were related to the distance between their home and the
street. A randomly selected sample of 100 property owners was contacted and the
results are shown next.
What is the computed value of chi-square?
The minimum and maximum of values of an F statistic are _______ and ______.