For Questions 1 – 2 use following data: According to the California Health Department, 24% of all delivered to ER residents had a car accident’s trauma. Research shown that out of information...

For Questions 1 – 2 use following data:

According to the California Health Department, 24% of all delivered to ER residents had a car accident’s trauma. Research shown that out of information collected in ER for 1,400 patients 320 had a car accident related trauma.

1.State the population parameter, and hypotheses.


2.
State the type I and type II errors in this case.
What type of error has worse consequences in this case?

3.
Local press reported that out of 32,600active cases of Coronavirus in Arkansas425 had fatal outcome. Nationally 1 out of 88 active cases have fatal outcome.CompleteHypothesis Testingat the 1% level. Consider distribution for sampling proportion as aNormal Distribution. UseTest Statistics z-value, and p-value to make the decision.

4.
Table belowshowsindex of growthfor somedesignated regionsin the United States.
CompleteHypothesis Testing at the 5% level to check if index of growth in these regions
isbelow 54 . Find Test Statistics, t-value, and p-value to make the decision.
Use t-Distribution.

5.
A serviceadvertises that it will take them in average 20 min to fix the problem.Independent contractor was hired to check how long it will really take to fix the common problem.Test was done nine times.
Table below shows collected results (sample data) in min.

Apply Hypothesis Testing at the 1% level to check if average time to fix the problem
takes 20 min.Find Test Statistics, t-value, and p-value to make the decision.

6.
Suppose you compute a confidence interval with a sample size of 100.What will happen to the confidence interval if the sample size decreases to 50? Explain your answer.