11. Carbon Monoxide in LA
The Environmental Protection Agency (EPA) conducted a test to assess if the
population average carbon monoxide level in the downtown Los Angeles area is higher than 4.9 parts per
The hypotheses tested were: H
= 4.9 versus H
> 4.9 and a 5% significance level was used. The results
from a random sample of 25 carbon monoxide readings gave a sample mean of 5.40, a sample standard
deviation of 1.03, a test statistic value of 2.43 with a corresponding
-value of 0.011.
statements for including in the EPA report.
You have been asked to determine which
statements are appropriate to include (True) and which are not appropriate to include (False). Clearly circle
your answer for each statement. [1 point each]
The value of 5% represents the tolerable risk of concluding the population
The power of the test is the probability that the EPA correctly concludes
The standard normal distribution was used to calculate the
-value of 0.011 is the probability that the null hypothesis is true.
Based on the data, the carbon monoxide level in all areas in downtown
12. Memory Experiment
A researcher conducts an experiment on human memory and recruits 10 people to
participate in her study. She performs the experiment and analyzes the results. She obtains a
0.13. Which of the following is a reasonable interpretation of her results? Her significance level was 10%.