Quizzes

Question 1

Calculate the Sample Average Treatment Effect (SATE) for the following data

Unit Treatment Outcome Group
1 1 20 T
2 1 15 T
3 1 25 T
4 0 4 C
5 0 5 C
6 0 6 C

Answer 1

Yt = (20+15+25)/3 = 60/3 = 20
Yc = (4+5+6)/3 = 15/3 = 5

SATE = 20-5 = 15

Question 2

If you were interested in having the most realistic experiment, which type of experiment would you pick and why?

Answer 2

Field experiment: gives a real-life setting that is the most realistic because it is out in the world and has randomized control trials

Question 3

What is a regression discontinuity design? Explain it in words and draw the graph.

Answer 3

key: a continuous score variable (x) and there’s an arbitrary cutoff that as-if randomly assigns observations to treatment (above cutoff) or control (below cutoff)

assumptions: cutoff’s arbitrary and well-enforced; no sorting w/ = # of treatment and control obs; covariates (2) won’t derail the effect

basically seeing if there is a jump at the cutoff and looking for a huge gap

Question 4

What are the dimensions of external validity?

Answer 4

Mechanism:
Setting, Treatment, Outcome, Unit, Time

Question 5

What is a mechanism?

Answer 5

Mechanisms represent the causal path through which our independent variable (𝑋) affects our dependent
variable (𝑌 ): that is, 𝑋 → 𝑀 → 𝑌 .
If researchers are unclear about the mechanism (𝑀 ), it is very hard to say that the inference is externally valid.