How This Works

Each card describes a real published study that used Regression Discontinuity Design. Read the scenario, then ask yourself:

• Running variable — What continuous variable determines who gets treated?
• Cutoff — At what value does treatment switch on?
• Treatment — What changes when you cross the cutoff?
• Outcome — What is being measured?

Click any box to check your answer, or click "Show Answer" to reveal everything — including a detailed explanation of why the RDD works, what the researchers found, and what makes the study interesting.