<p>The paper computes the value of your coefficient $\gamma$ on its own with comparison to $\alpha +\gamma$<sup>1</sup>.</p>

<p>The interpretation in this context, would be that there is a limit of the returns to <strong>RightShare</strong> given the presence of observations existing contemporaneously with <strong>RightPM</strong> and <strong>InRange</strong>.</p>

<hr>

<p><sub>1. this of course assumes that $z=1$</sub></p>

CC BY-SA 3.0
2017-12-31T17:17:58.937Z
2017-12-31T17:17:58.937Z
EconJohn
<p>I'm reading a paper that tries to estimate the following model:
$$y = \alpha x+\beta z+\gamma xz+\epsilon$$
where x,z are dummy variables and y isn't. 
The estimated coefficient of $\alpha$ is positive (0.02), and the sum of $\alpha+\gamma$ is negative (-0.01,insignificant). The writer examines the marginal effect of x, conditional on z and finds a positive (0.01, with significant of 90%). 
My question is what is the difference in interpretation of marginal effect VS. $\alpha+\gamma$?</p>

<p>The paper is "Terrorism and Voting: The Effect of Rocket Threat on Voting in Israeli Elections" by Anna Getmansky and Thomas Zeitzoff (link: <a href="https://www.zeitzoff.com/uploads/2/2/4/1/22413724/zeitzoff_getmank_rockets_main.pdf" rel="nofollow noreferrer">https://www.zeitzoff.com/uploads/2/2/4/1/22413724/zeitzoff_getmank_rockets_main.pdf</a>).
The marginal analysis is on page 11.</p>

CC BY-SA 3.0
2017-12-31T16:22:29.297Z
can you include a link to the paper you are referencing?
EconJohn
CC BY-SA 3.0
2017-12-31T17:02:57.210Z
I added a link.
Neta_1990
CC BY-SA 3.0
2017-12-31T17:20:21.660Z
Wow, I didn't know they did quantitative work on this. Seems like a little bit of a wild topic to be researching.
EconJohn
CC BY-SA 3.0
2017-12-31T19:22:09.197Z
@Neta_1990 I edited the title of your question. Please edit the title again if you feel my edit was inaccurate.
Theoretical Economist
<econometrics>
Marginal Effects Interpretation
Neta_1990
# Marginal Effects Interpretation

(Asked by: username_0 on 2017-12-29)

I'm reading a paper that tries to estimate the following model:
$$y = \alpha x+\beta z+\gamma xz+\epsilon$$
where x,z are dummy variables and y isn't.
The estimated coefficient of $\alpha$ is positive (0.02), and the sum of $\alpha+\gamma$ is negative (-0.01,insignificant). The writer examines the marginal effect of x, conditional on z and finds a positive (0.01, with significant of 90%).
My question is what is the difference in interpretation of marginal effect VS. $\alpha+\gamma$?

The paper is "Terrorism and Voting: The Effect of Rocket Threat on Voting in Israeli Elections" by Anna Getmansky and Thomas Zeitzoff (link: <https://www.zeitzoff.com/uploads/2/2/4/1/22413724/zeitzoff_getmank_rockets_main.pdf>).
The marginal analysis is on page 11.

**Tags:** econometrics

> **Comments:**
> **username_1**: can you include a link to the paper you are referencing?  
> **username_0**: I added a link.  
> **username_1**: Wow, I didn't know they did quantitative work on this. Seems like a little bit of a wild topic to be researching.  
> **username_2**: @username_0 I edited the title of your question. Please edit the title again if you feel my edit was inaccurate.  

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## 1 answers

### Answer by username_1 on 2017-12-31. Score: 1

The paper computes the value of your coefficient $\gamma$ on its own with comparison to $\alpha +\gamma$1.

The interpretation in this context, would be that there is a limit of the returns to **RightShare** given the presence of observations existing contemporaneously with **RightPM** and **InRange**.

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1. this of course assumes that $z=1$


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