# Re: st: RE: RE: Simulation: marginal effect at the 5th percentile

 From "Supnithadnaporn, Anupit" To statalist@hsphsun2.harvard.edu Subject Re: st: RE: RE: Simulation: marginal effect at the 5th percentile Date Tue, 2 Dec 2008 21:01:39 -0500 (EST)

```Hello all,

----- "Martin Weiss" <martin.weiss1@gmx.de> wrote:
> On the occasion of this thread: Is capitalization in the names of
> returned results really advisable? - e(Xmfx_dydx)- may be used less frequently,
> but I remember being bitten by -r(var)- as opposed to -r(Var)- after -sum-.
> What is the benefit of a capitalized "V" here?

Thank you Martin. Your code -loc ap5 = r(p5)- after -sum a, detail- works fine.
Also, I really appreciate your careful looking at my code and finding about typos
In fact, I got an error from -r(var)- exactly like you just told me. Well, I made all the typos here because I did not copy my code exactly from my program. I try
to simplify and focus on my problem.

Also, thank you Marrten for your suggestion. I will try out your suggestion
next.

help educate me about Stata programming.

1) For the 2 ways of coding, which one is faster in terms of simulating time.
Also, for the first way, -r(p5)- has a specific reference to the 5th percentile
from the -sum, detail- command, right? When I look at -r(r1)-, how and what
would this refer to?

1st way:  sum a, detail
loc ap5 = r(p5)

2nd way: _pctile a, p(5)
loc ap5 = r(r1)

2) I have tried to run your suggested program (copy and paste it in the do and
run). I got an error saying

class system failure
class system failure
class system failure
class system failure
class system failure
class system failure
--more--

I did -set trace on- and see a lot of red characters in many places. Also the
-trace- output seems very long. I am not sure I should post it here.
What would be the problem here?

Thank you very much,
Anupit

PS I am using Stata SE 9 on Window Vista Home

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