20.06.2013 Views

Binary Models with Endogenous Explanatory Variables 1 ... - Cemfi

Binary Models with Endogenous Explanatory Variables 1 ... - Cemfi

Binary Models with Endogenous Explanatory Variables 1 ... - Cemfi

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Local average treatment effects (LATE) Considerthecasewhere<br />

X = 1 (π0 + π1Z + V ≥ 0)<br />

and Z is a scalar 0—1 instrument, so that there are only two potential values of X:<br />

X (1) = 1 (π0 + π1 + V ≥ 0)<br />

X (0) = 1 (π0 + V ≥ 0) .<br />

Suppose <strong>with</strong>out lack of generality that π1<br />

depending on an individual’s value of V :<br />

≥ 0. Then we can distinguish three subpopulations<br />

• Never-takers: Units <strong>with</strong> V < −π0 − π1. They have X (1) = 0 and X (0) = 0. Their mass is<br />

Φ (−π0 − π1) =1− Φ (π0 + π1).<br />

• Compliers: Units <strong>with</strong> V ≥−π0 − π1 but V

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!