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Re: st: RE: RE: RE: adding to X to make ln(X) nonmissing [was BTSCS and Non-linear MLE programming]


From   aslihan arslan <aslihanarslan@yahoo.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: RE: RE: RE: adding to X to make ln(X) nonmissing [was BTSCS and Non-linear MLE programming]
Date   Sun, 4 Feb 2007 18:46:34 -0800 (PST)

Thank you for all your thoughts&suggestions, they are
very helpful...

Regards, 
aslihan

--- Nick Cox <n.j.cox@durham.ac.uk> wrote:

> Thanks for the suggestion and the reference. 
> 
> My help -transint-, referred to by Austin in his
> email 
> to which I replied, which remains in the material
> below, also 
> refers to this transformation. 
> 
> I agree that in general considering quite a
> different 
> transformation is part of the possibilities, but 
> it isn't really a solution to the specific question 
> I posed myself in the pseudo-FAQ I have below. 
> 
> Nick 
> n.j.cox@durham.ac.uk 
> 
> Benito, Andrew
> 
> > I wld suggest looking at the following reference
> > 
> >     Burbidge, J.B., Magee, L. and Robb, L. (1988),
> 
> > `Alternative Transformations to Handle Extreme
> Values of the 
> > Dependent Variable', Journal of the American
> Statistical 
> > Association, 83, 123-7.
> >     
> > It suggests using an Inverse hyperbolic sine
> function to 
> > replace the log in such cases. (related to Nick's
> point(d)). 
> > The functional form, with the dampening factor set
> to 1, is 
> > sinh⁻¹(x)=ln(n+√(1+x²)).  But more generally
> (ie without the 
> > dampening factor set in that way), it involves
> non-linear estimation.
> 
> Nick Cox
>  
> > Let me summarise the situation as I see it. This
> tries a 
> > slightly more general pitch than the current
> thread. 
> > 
> > I want to work with the logarithm of a variable,
> but that 
> > variable contains zero values. What should I do? 
> >
>
---------------------------------------------------------
> 
> < snip >  
>  
> Austin Nichols
>   
> > > In re: adding alpha to X to make ln(X)
> nonmissing Why does this 
> > > operation come up so often, when it is so often
> a bad idea?  I have 
> > > seen several papers this week that add some
> constant to X so that 
> > > ln(X) can be regressed on some variables, or
> some variable can be 
> > > regressed on it.  Wouldn't you be just as well
> off imputing
> > > 2*atan(X)-2*atan(1) or somesuch?  Is there a
> well-known 
> > good reference 
> > > on this subject?
> > > 
> > > Just now, when looking up the ref for an
> adjacent thread on 
> > btscs.ado, 
> > > I ran across Oneal & Russett (2001) which
> acknowledges that Beck, 
> > > Katz, and Tucker (1998) pointed out an error,
> and then replies to 
> > > another critique with this (p.480):
> > > "
> > > Before taking the logarithm [of trade volume in
> $millions] 
> > we assigned 
> > > a different value to the trade variable for
> dyads that report no 
> > > trade.  Some value must be imputed because the
> logarithm of zero is 
> > > undefined.  We use $100,000 [so really it was
> ln(0.1)]; Green, Kim, 
> > > and Yoon used $1.  It is this that accounts for
> most of the 
> > > differences between our results and theirs.
> > > "
> > > Oneal, John R. and Bruce Russett. 2001. Clear
> and Clean: The Fixed 
> > > Effects of the Liberal Peace. International
> Organization, 
> > Vol. 55, No.
> > > 2. (Spring, 2001), pp. 469-485.
> > >
>
http://links.jstor.org/sici?sici=0020-8183%28200121%2955%3A2%3
> > > C469%3ACACTFE%3E2.0.CO%3B2-A
> > > 
> > > Green, Donald P., Soo Yeon Kim, and David H.
> Yoon. 2001. 
> > "Dirty Pool."
> > > International Organization, Vol. 55, No. 2.
> (Spring, 2001), pp.
> > > 441-468.
> > >
>
http://links.jstor.org/sici?sici=0020-8183%28200121%2955%3A2%3
> > C441%3ADP%3E2.0.CO%3B2-N
> > 
> > Beck, Nathaniel, Jonathan N. Katz and Richard
> Tucker. 1998. 
> > Taking Time Seriously: Time-Series-Cross-Section
> Analysis 
> > with a Binary Dependent Variable. American Journal
> of 
> > Political Science, 42:
> > 1260-1288.
> > 
> > See also:
> > ssc install transint
> > h transint
> >
>
http://www.stata.com/statalist/archive/2006-11/msg00294.html
> > 
> 
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