log transformation

Previous Topic Next Topic
 
classic Classic list List threaded Threaded
2 messages Options
Reply | Threaded
Open this post in threaded view
|

log transformation

jarry

Hi,

I am reading an article in which, first, some given "p-results" are obtained, and, second, these are afterwards transformed and expressed as the "NEGATIVE base-10 logarithm of the p-value".

My question is if anyone could indicate how is such transformation achieved with R and how are they expressed exponentially, as in for example 1.8E-18.

Thank you!
Reply | Threaded
Open this post in threaded view
|

Re: log transformation

bbolker
jarry <jarryjarry58 <at> hotmail.com> writes:

>
>
> Hi,
>
> I am reading an article in which, first, some given "p-results" are
> obtained, and, second, these are afterwards transformed and expressed as the
> "NEGATIVE base-10 logarithm of the p-value".
>
> My question is if anyone could indicate how is such transformation achieved
> with R and how are they expressed exponentially, as in for example 1.8E-18.
>

  ?? presumably

 -log10(pvalue)

  ??

  so a p-value of 1.8e-18 (i.e., 1.8 times 10^-18) would correspond to
a value of 17.74

______________________________________________
[hidden email] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.