4.26 Assumptions: Exercise

Q: Below you find three examples for planned experiments. Discuss in groups of 2 or 3.
- What may lead to a violation of the independence assumption?
- What may lead to a violation of the SUTVA assumption?
Fertilizer (D_i) → plot yields (Y_i)
- Half of the plots on a corn field are randomly treated with fertilizer
Job-training programme (D_i) → Unemployment (Y_i)
- Half of Mannheim’s unemployed are randomly assigned to a job training program
AIDS drug (D_i) → survival (Y_i)
- 50% of the AIDS patients at a hospital are randomly assigned a drug in a placebo trial²⁶