Dear Group,
I am using the ecdf function as follows:
cawa.cdp <- ecdf(cawaocc$LEFF80)
summary(cawa.cdp)
Empirical CDF: 223 unique values with summary
Min. 1st Qu. Median Mean 3rd Qu. Max.
0.07918 1.35700 1.68600 1.61000 1.91200 2.70000
I can see by the summary that the y-value for the 3rd quartile is 1.912.
How can I obtain the x-value for a specified y-value (e.g., 0.8)?
Thank you!
--
Benjamin Zuckerberg
Doctoral Candidate
State University of New York
College of Environmental Science and Forestry
Illick 244A, 1 Forestry Drive
Syracuse, New York 13210
Tele: (315) 470-6985
E-mail: bzuckerb at syr.edu
try this: knots(cawa.cdp) -- Henrique Dallazuanna Curitiba-Paran?-Brasil 25? 25' 40" S 49? 16' 22" O On 18/11/2007, Benjamin Zuckerberg <bzuckerb at syr.edu> wrote:> > Dear Group, > > I am using the ecdf function as follows: > > cawa.cdp <- ecdf(cawaocc$LEFF80) > > summary(cawa.cdp) > > Empirical CDF: 223 unique values with summary > Min. 1st Qu. Median Mean 3rd Qu. Max. > 0.07918 1.35700 1.68600 1.61000 1.91200 2.70000 > > I can see by the summary that the y-value for the 3rd quartile is 1.912. > > How can I obtain the x-value for a specified y-value (e.g., 0.8)? > > > Thank you! > > > -- > Benjamin Zuckerberg > Doctoral Candidate > State University of New York > College of Environmental Science and Forestry > Illick 244A, 1 Forestry Drive > Syracuse, New York 13210 > Tele: (315) 470-6985 > E-mail: bzuckerb at syr.edu > > ______________________________________________ > 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. >
That would give the x-values. He asked for the y-values at a particular x. Instead he might try: quantile(cawaocc$LEFF80, probs=0.8) or quantile(knots(Fn), probs=0.8) -- David Winsemius Henrique Dallazuanna wrote:> try this: > > knots(cawa.cdp) > >On 18/11/2007, Benjamin Zuckerberg <bzuckerb at syr.edu> wrote:> > > > Dear Group, > > > > I am using the ecdf function as follows: > > > > cawa.cdp <- ecdf(cawaocc$LEFF80) > > > > summary(cawa.cdp) > > > > Empirical CDF: 223 unique values with summary > > Min. 1st Qu. Median Mean 3rd Qu. Max. > > 0.07918 1.35700 1.68600 1.61000 1.91200 2.70000 > > > > I can see by the summary that the y-value for the 3rd quartile is 1.912. > > > > How can I obtain the x-value for a specified y-value (e.g., 0.8)?