<p>I had a look at the data, and it is like @denesp says in his comment: e.g. a $2.60\%=0.0261$ population growth rate is written as $2.60$, a $24\%=0.24$ investment-to-output ratio is written like $24.0$, etc. 
So they must be divided by $100$.</p>

CC BY-SA 3.0
2016-03-30T12:46:36.730Z
Thanks Alecos. You're right. I don't know how I missed that ... =D
An old man in the sea.
CC BY-SA 3.0
2016-03-29T23:46:41.710Z
2016-03-29T23:46:41.710Z
Alecos Papadopoulos
<p>I'm trying to replicate the regression of the <a href="http://dx.doi.org/10.2307/2118477" rel="nofollow">MRW 1992</a> paper.
(<a href="https://www.nuffield.ox.ac.uk/teaching/economics/bond/mrw.dta" rel="nofollow">Here's</a> the data, if you're interested)</p>

<p>In the same page where the data set is available, there's this <a href="https://www.nuffield.ox.ac.uk/teaching/economics/bond/OLS%20Regression%20Using%20Stata.pdf" rel="nofollow">handout</a> explaining how to replicate the results. In page 2 of this handout, we can see two simple stata commands: </p>

<pre><code>li_y=ln(i_y/100) 
 g lpop=ln(0.05+popgrowth/100)
</code></pre>

<p>My question is why the variables <code>i_y</code> (this is Investment over GDP), and <code>popgrowth</code>(this is an averaged population growth rate between 1960-1985) are divided by 100?</p>

<p>Nowhere in the MRW 1992 paper, do I read something telling me that it's necessary to divide it by 100, or do I?</p>

<p>Any help would be appreciated</p>

CC BY-SA 3.0
2016-03-29T23:05:26.933Z
Perhaps in the data they are given as percentage points?
Giskard
CC BY-SA 3.0
2016-03-31T04:05:16.123Z
It's just a scaling factor get everything as a decimal.
D J Sims
CC BY-SA 3.0
2016-05-08T16:48:15.323Z
Are you aware of the [2013 replication](http://replication.uni-goettingen.de/wiki/index.php/Is_newer_better%3F_Penn_World_Table_Revisions_and_their_impact_on_growth_estimates_(JME_2013))?
Jan Höffler
<macroeconomics>
A doubt on the Regression of Mankiw, Romer, Weil 1992 paper
An old man in the sea.
# A doubt on the Regression of Mankiw, Romer, Weil 1992 paper

(Asked by: username_0 on 2016-03-29)

I'm trying to replicate the regression of the MRW 1992 paper.
(Here's the data, if you're interested)
In the same page where the data set is available, there's this handout explaining how to replicate the results. In page 2 of this handout, we can see two simple stata commands: 
li_y=ln(i_y/100) 
 g lpop=ln(0.05+popgrowth/100)

My question is why the variables i_y (this is Investment over GDP), and popgrowth(this is an averaged population growth rate between 1960-1985) are divided by 100?
Nowhere in the MRW 1992 paper, do I read something telling me that it's necessary to divide it by 100, or do I?
Any help would be appreciated

**Tags:** macroeconomics

> **Comments:**
> **username_1**: Perhaps in the data they are given as percentage points?  
> **username_2**: It's just a scaling factor get everything as a decimal.  
> **username_3**: Are you aware of the [2013 replication](http://replication.uni-goettingen.de/wiki/index.php/Is_newer_better%3F_Penn_World_Table_Revisions_and_their_impact_on_growth_estimates_(JME_2013))?  

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## 1 answers

### Answer by username_4 on 2016-03-29. Score: 2 | Accepted answer

I had a look at the data, and it is like @denesp says in his comment: e.g. a $2.60\%=0.0261$ population growth rate is written as $2.60$, a $24\%=0.24$ investment-to-output ratio is written like $24.0$, etc.
So they must be divided by $100$.

> **Comments:**
> **username_0**: Thanks Alecos. You're right. I don't know how I missed that ... =D  

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