Interference

Study: School Attendance

A school district in a large city wants to boost student attendance rates. They identify 20,000 households, each containing exactly two enrolled students. In 10,000 randomly-chosen households, the parents receive no mail. In the remaining 10,000 households, the parents receive a letter about one of their two children, chosen at random. Attendance rates are then measured for the remainder of the school year for all children.

Measurement unit? Experimental Unit? Response? Factors? Design?

Study: School Attendance

  • Measurement unit: student
  • Experimental unit: student and household
  • Response: attendance rate
  • Experimental factor: mail (yes/no)
  • Design: Mix of cluster design (household is cluster) and CB (block is household).

This multistage design is specifically constructed to handle interference.

Question: How many potential outcomes are needed to represent this design?

3: \(Y_{ij}(1, 0), Y_{ij}(0, 1), Y_{ij}(0, 0)\)