Difference between revisions of "Hornbeck (2010)"

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imported>Moshe
imported>Moshe
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Since <math>\frac{\partial P}{\partial C_{p}} < 0</math> we know that an estimate of <math>\frac{\partial I}{\partial C_{p}}</math> is informative about the sign of <math>\frac{\partial I}{\partial P}</math>
 
Since <math>\frac{\partial P}{\partial C_{p}} < 0</math> we know that an estimate of <math>\frac{\partial I}{\partial C_{p}}</math> is informative about the sign of <math>\frac{\partial I}{\partial P}</math>
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So, we can think of <math>\frac{\partial I}{\partial C_{p}}</math> as the "reduced form" where marginal cost of protection is an instrumental variable.  Since we do not have data on protection levels, we can not estimate the "first stage" and recover <math>\frac{\partial I}{\partial P}</math>.
  
 
===  How does the author test the hypothesis? ===
 
===  How does the author test the hypothesis? ===

Revision as of 23:53, 15 May 2012

Return to BPP Field Exam Papers 2012

Empirical Questions:

What is the author's topic and hypothesis?

This paper examines the impact on agricultural development from a decrease in the cost of protecting farmland. Barbed wire appears to have had a substantial impact on agriculture development in the US and in particular, this may reflect an important role for protecting land and securing farmers' full bundle of property rights.

Theoretical Framework: [math]\frac{\partial I}{\partial C_{p}}=\frac{\partial I}{\partial P} \cdot \frac{\partial P}{\partial C_{p}}[/math]

The effect on Investment from a change in cost of protection equals the change in Investment from a change in protection multiplied by the change in protection from a change in cost of protection.

Since [math]\frac{\partial P}{\partial C_{p}} \lt 0[/math] we know that an estimate of [math]\frac{\partial I}{\partial C_{p}}[/math] is informative about the sign of [math]\frac{\partial I}{\partial P}[/math]

So, we can think of [math]\frac{\partial I}{\partial C_{p}}[/math] as the "reduced form" where marginal cost of protection is an instrumental variable. Since we do not have data on protection levels, we can not estimate the "first stage" and recover [math]\frac{\partial I}{\partial P}[/math].

How does the author test the hypothesis?

What do the authors tests achieve?

How could the tests be improved on? Strengths? Weaknesses?

What are some alternative empirical strategies

How does the author rule out alternative hypotheses?