}{Pct. Compliant} \)`

We need to observe compliance to estimate the *LATE*

???

If we expect noncompliance, we need to measure it

Otherwise all we can estimate is the ITT

This is easy if the treatment is a phone call, we can record compliance easily

This is harder if the treatment is something that we don't actually administer (e.g., drugs taken at home)


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## Two-sided noncompliance

 1. This is more complex analytically
 
 2. Stronger assumptions are required to analyze it
   - Especially *monoton