Table 2.
Responder Behaviour W.
| W | Type | R(0) | R(1) |
|---|---|---|---|
| a | Always-respond (never drops out) | 1 | 1 |
| t | Test-only responder (drops out only if zi = 0) | 0 | 1 |
| c | Control-only responder (drops out only if zi = 1) | 1 | 0 |
| n | Never-responder (always drops out) | 0 | 0 |
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