28 Mar Ask someone to make a ‘guess’ about the mean number (μ ) of the positivity rate of COVID-19 cases from the state that you chose in Phase 1
Use the data/information from Phases 1, 2 and 3 to complete this project. For the purposes of this
assignment, assume that the population is approximately normally distributed.
1. a. Ask someone to make a ‘guess’ about the mean number (μ ) of the positivity rate of COVID-19 cases from the state that you chose in Phase 1. Clearly state the claim about the mean of your population in words with the “guess (μ )” from the person you asked. For example, “It is believed that the mean positivity rate of COVID- 19 cases in (state) is less than/greater than/different than (the guess).”
Calculate and write the population standard deviation, the sample standard deviation and sample mean for the positivity rate of the 40 randomly chosen counties you obtained in Phase 1. You can get this information by using your calculator’s statistical feature or by using the appropriate formula. [3 pts]
b. Perform a left-tailed hypothesis test at the 0.01 level of significance. Be creative and write out a scenario that will lead up to the claim based on the test to be performed. You will use the rejection region method to draw the conclusion. Use the population standard deviation.
[8 pts]
c. Perform a right-tailed hypothesis test at the 0.05 level of significance. Be creative and write out a scenario that will lead up to the claim based on the test to be performed. You will use the p-value method to draw the conclusion. Use the sample standard deviation. [9 pts]
d. Perform a two-tailed hypothesis test at the 0.01 level of significance. Be creative and write out a scenario that will lead up to the claim based on the test to be performed. You can use the rejection region or the p-value method to draw the conclusion. Use the sample standard
deviation.
2. Ask someone to make a ‘guess’ about the percentage of more than 900 COVID-19 cases in your chosen state. Clearly state the claim about the proportion of your population in words with the “guess (p)” from the person you asked. The guess will be used as the population proportion (p). Be creative and write out a scenario that will lead up to the claim that the proportion is different.
Using the sample proportion that you had in Phase 3 – 5(a) as p. [2 pts]
Perform a two-tailed hypothesis test at the 0.02 level of significance. You can use the rejection
region or the p-value method to draw the conclusion. [9 pts]
For each, use the four steps that have been discussed in class, clearly and neatly showing all your work and diagrams. Don’t forget to interpret your conclusions in context.
