Q2. Hypothesis Testing with a Z Test (7.5 points)

According to the CDC report, the mean life expectancy in the US population is currently () 78.2 years with a standard deviation () of 9.6. A researcher examined the age of death of 70 people recently recorded in several Vermont hospitals and calculated the mean to be 81.3 years old. He runs a two-tailed Z test with = .05 to see if Vermont has a significantly different life expectancy compared to the US population. Because the researcher is not predicting a direction, the hypotheses should be non-directional, and the test should be two-tailed.

Q2a. What is the dependent variable in this research question? [.5 point]

Q2b. What should the null and alternative hypotheses? State each hypothesis using both words and statistical symbol notation. [2 points] 1 for each hypothesis: 0.5 for written, 0.5 for notation

	Written	Symbolic Symbol bank for copy & pasting: = < > m
Null		H0:
Alternative		H1:

Q2c. Calculate standard error (SE, which is the standard deviation of the sampling distribution) Round the result to the hundredth (2^nd place to the right of the decimal). [1 point] 0.5 if the process is correct but the result was calculated incorrectly

Q2d. Calculate the Z statistic (which indicates where our sample mean is located on the sampling distribution) Round the result to the hundredth (2^nd place to the right of the decimal). [1 point] 0.5 if the process is correct but the result was calculated incorrectly

Q2e. Determine the critical Z value(s). Explain how you find the answer. [1 point] 0.5 for the Z value, 0.5 for the rationale, deduct 0.5 if only one Z value is mentioned

Q2f. Compare the Z statistic with the appropriate critical Z value and then draw a conclusion about the result of the hypothesis test. What is the answer to the research question now?

- Do you "reject" or "fail to reject" the null hypothesis? [0.5 point]

- What is the answer to the research question? [0.5 point]

Q2g. Calculate the standardized effect size. Round the result to the hundredth (2^nd place to the right of the decimal). [1 point total] deduct 0.5 if the process is correct but the result was calculated incorrectly