Practice Final
1
Problem 1 Identifying elements of a study and appropriate statistical inference
From January 5 to 7, 2015, Hart Research Associates conducted a national survey on the issue of the federal minimum
wage. Interviews were conducted online among a representative national sample of 1,002 adults.
Respondents
answered the following question:
“Do you support raising the federal minimum wage to $15.00/hour over the next 5
years?”.
The only options were "Support" and "Do not support".
The
survey results showed that 63% of those who
responded supported this proposal.
1.1
What kind of study is this?
a)
Cross-sectional survey
b)
Prospective longitudinal cohort
c)
Case-control study
d)
Cross-sectional experiment
e)
None of the above

1.2
What is the population parameter of interest?

1.3
What is the distribution of the individual-level outcome in the population?

1.4
What is the distribution of the combination of outcomes in the population?

1.5
What is the sample estimate of the
population parameter, and what is its
approximate sampling distribution?
(formula with expected value and
standard deviation)
𝑝̂ ~ ? (𝑝,
√
𝑝(1 − 𝑝)
?
)
1.6
How do we define the sampling
distribution of the estimate for testing
the null hypothesis
𝐻
0
: 𝑝 = 𝑝
0
? (𝑝
0
,
√
𝑝
0
(1 − 𝑝
0
)
?
)
?

Practice Final
2
1.7
How do we define the sampling
distribution of the estimate for
constructing a confidence interval?
1.8
Plug in the values for the expected

value and variance you would use for a
confidence interval.
The poll was reported to have a margin of error of ± 3.1%.
What is the formula they used to calculate this
value, and what values would you plug in to obtain a 95% confidence interval?
√

Practice Final
3