extracting p-values in scientific notation
One point to note, for information, in this discussion is that cor.test() has apparently returned the P-value as an exact zero: x$p.value == 0 # [1] TRUE identical(x$p.value, 0) # [1] TRUE (which, by the way, I was led to after trying log10(x$p.value) and getting -Inf). Perhaps a more interesting question is how cor.test computes the P-value! Ted.
On 03-Oct-11 08:48:31, Kenn Konstabel wrote:
is(x)
[1] "htest"
# take a look at stats:::print.htest format.pval(x$p.value)
[1] "< 2.22e-16" Does that answer your question? KK On Mon, Oct 3, 2011 at 10:53 AM, Liviu Andronic <landronimirc at gmail.com> wrote:
Dear all How does print.htest display the p-value in scientific notation?
(x <- cor.test(iris[[1]], iris[[3]]))
_ _ _ _Pearson's product-moment correlation data: _iris[[1]] and iris[[3]] t = 21.65, df = 148, p-value < 2.2e-16 alternative hypothesis: true correlation is not equal to 0 95 percent confidence interval: _0.8270 0.9055 sample estimates: _ cor 0.8718 Above the p-value comes as '< 2.2e-16', while inspecting the object I get a good old '0'.
x$p.value
[1] 0 I tried to inspect print.htest but couldn't find it. I also played with format, round and the like to no avail. Any pointers? Regards Liviu -- Do you know how to read? http://www.alienetworks.com/srtest.cfm http://goodies.xfce.org/projects/applications/xfce4-dict#speed-reader Do you know how to write? http://garbl.home.comcast.net/~garbl/stylemanual/e.htm#e-mail
______________________________________________ R-help at r-project.org 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.
______________________________________________ R-help at r-project.org 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.
-------------------------------------------------------------------- E-Mail: (Ted Harding) <ted.harding at wlandres.net> Fax-to-email: +44 (0)870 094 0861 Date: 03-Oct-11 Time: 10:05:50 ------------------------------ XFMail ------------------------------