PAC Research Methodologies & Data Analysis 2

Question 1

A policy analyst wants to determine whether a new job training program caused a reduction in unemployment. Which research design best establishes causality?

Accepted Answer

Randomized controlled trial with treatment and control groups

Answer

Randomized controlled trials (RCTs) are the gold standard for establishing causality because random assignment eliminates selection bias.

Question 2

When conducting a difference-in-differences (DiD) analysis, what is the key assumption that must hold?

Accepted Answer

Both groups would have followed parallel trends absent the intervention

Answer

The parallel trends assumption holds that in the absence of treatment, the average outcomes for treatment and control groups would have followed the same trend over time.

Question 3

A dataset on household income contains values ranging from $20,000 to $500,000 with several extreme outliers above $2 million. Which measure of central tendency best represents the typical household income?

Accepted Answer

Median

Answer

The median is resistant to extreme outliers, making it the best measure of central tendency for skewed income distributions.

Question 4

In regression analysis, multicollinearity occurs when two or more independent variables are highly correlated. What is the primary problem this causes?

Accepted Answer

It makes coefficient estimates unstable and difficult to interpret

Answer

Multicollinearity inflates the standard errors of correlated predictors, making individual coefficient estimates unreliable even if the overall model fits well.

Question 5

A policy researcher uses a Likert scale (1–5) to measure public satisfaction with government services. This type of data is best classified as:

Accepted Answer

Ordinal

Answer

Likert scale data is ordinal because responses have a meaningful order, but the intervals between points are not necessarily equal.

(PAC) Policy Analyst Certification Practice Test

(PAC) Policy Analyst Certification Practice Test

PAC Research Methodologies & Data Analysis 2