Significance level to test the claim that with garlic treatment
1. Consider a drug that is used to help prevent blood clots in certain patients. In clinical trials, among
5798 patients treated with this drug,
157 developed the adverse reaction of nausea. Use a
0.10 significance level to test the claim that
3% of users develop nausea. Does nausea appear to be a problematic adverse reaction?
2.Suppose
221 subjects are treated with a drug that is used to treat pain and
55 of them developed nausea. Use a
0.01 significance level to test the claim that more than
20% of users develop nausea.
3.Consider a drug testing company that provides a test for marijuana usage. Among
326 tested subjects, results from
26 subjects were wrong (either a false positive or a false negative). Use a
0.10 significance level to test the claim that less than
10 percent of the test results are wrong.
4.A 9-year-old girl did a science fair experiment in which she tested professional touch therapists to see if
they could sense her energy field. She flipped a coin to select either her right hand or her left hand, and
then she asked the therapists to identify the selected hand by placing their hand just under her hand
without seeing it and without touching it. Among
288 trials, the touch therapists were correct
118 times. Use a
0.01 significance level to test the claim that touch therapists use a method equivalent to random guesses.
Do the results suggest that touch therapists are effective?
5.In one study of smokers who tried to quit smoking with nicotine patch therapy,
36 were smoking one year after treatment and
35 were not smoking one year after the treatment. Use a
0.10 significance level to test the claim that among smokers who try to quit with nicotine patch therapy,
the majority are smoking one year after the treatment. Do these results suggest that the nicotine patch
therapy is not effective?
6. A data set includes data from student evaluations of courses. The summary statistics are n
=
85,
x
=
3.44, s
=
0.59. Use a
0.05 significance level to test the claim that the population of student course evaluations has a mean
equal to
3.50. Assume that a simple random sample has been selected. Identify the null and alternative
hypotheses, test statistic, P-value, and state the final conclusion that addresses the original claim.
7. In a test of the effectiveness of garlic for lowering cholesterol,
49 subjects were treated with raw garlic. Cholesterol levels were measured before and after the
treatment. The changes (before minus after) in their levels of LDL cholesterol (in mg/dL) have a mean of
0.4 and a standard deviation of
2.46. Use a
0.01 significance level to test the claim that with garlic treatment, the mean change in LDL cholesterol is
greater than
0. What do the results suggest about the effectiveness of the garlic treatment? Assume that a simple
random sample has been selected. Identify the null and alternative hypotheses, test statistic, P-value, and
state the final conclusion that addresses the original claim.
8. A data set lists earthquake depths. The summary statistics are n
=
500,
x
=
4.37 km, s
=
4.24 km. Use a
0.01 significance level to test the claim of a seismologist that these earthquakes are from a population
with a mean equal to
4.00. Assume that a simple random sample has been selected. Identify the null and alternative
hypotheses, test statistic, P-value, and state the final conclusion that addresses the original claim.
9. Listed below are the lead concentrations in
μg/g measured in different traditional medicines. Use a
0.01 significance level to test the claim that the mean lead concentration for all such medicines is less
than
16
μg/g. Assume that the sample is a simple random sample.
13.5 11 5.5 22.5 18 22 2.5 21.5 4.5 5
10. Assume that a simple random sample has been selected from a normally distributed population and
test the given claim. Identify the null and alternative hypotheses, test statistic, P-value, and state the final
conclusion that addresses the original claim.
A safety administration conducted crash tests of child booster seats for cars. Listed below are results from
those tests, with the measurements given in hic (standard head injury condition units). The safety
requirement is that the hic measurement should be less than 1000 hic. Use a
0.01 significance level to test the claim that the sample is from a population with a mean less than 1000
hic. Do the results suggest that all of the child booster seats meet the specified requirement?