[R] Calculate negative log of the E-Values in R

[John Sorkin]

Actually  E is not "just a computer way of saying 0". The E represents a power of 10, thus E-1 = 0.1 e-2=0.01; E therefore is not zero. Because computers generally can not perform exact calculations (for reasons including the fact that our number system is base 10 and a computer's is generally base 2) what might otherwise be a zero is often represented by a very small number such as the one you listed. 4E-108 would be 4x10^-108, a very small number indeed that is (for most but not all purposes) the same as zero.
John 

> John David Sorkin M.D., Ph.D.
> Professor of Medicine
> Chief, Biostatistics and Informatics
> University of Maryland School of Medicine Division of Gerontology and Geriatric Medicine
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> On Feb 26, 2016, at 12:29 PM, Francesco Romano <francescobryanromano at gmail.com> wrote:
> 
> Sema, E is just a computer way of saying 0. For the purpose of statistical
> analysis, if you can't compute a calculation with E values (i.e. 0),
> substitute all E values with a usable constant, say 50. I stumbled across a
> few websites lately that did this.
> 
> Frank Romano Ph.D.
> 
> *Academia.edu*
> https://sheffield.academia.edu/FrancescoRomano
> 
> 
> On Fri, Feb 26, 2016 at 10:53 AM, Sema Atasever <s.atasever at gmail.com>
> wrote:
> 
>> Dear Authorized Sir / Madam,
>> 
>> If you don't mind, I want to ask how can i calculate negative log of the
>> E-Values in R.
>> 
>> *For Example: *
>> What is the negative log of the 4e-108?
>> 
>> I would appreciate if you could advise me some methods.
>> 
>> Thanks in advance.
>> 
>>        [[alternative HTML version deleted]]
>> 
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>> 
> 
> 
> 
> --
> 
>    [[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
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