Actually, the issue is that the left hand side of the model formula should be the name of the variable under consideration. If you write y ~ 1 there had better be a "y", but without the renaming you could also have used H_to_fit.Height ~ 1.
-pd > On 10 Mar 2016, at 19:03 , John Hillier <j.hill...@lboro.ac.uk> wrote: > > Dear Peter, > > Thank you. Apolgies for not looking closer. It is the end of a long day. > Fixed now, and I have learnt more about correctly interpreting R's manual > pages. > > For the record .... > > Summary: If input to truncpareto() is not explicitly called 'y' it can > produce error messages about the values 'lower', which might be confusing. > So, ensure input is called 'y', and that 'lower' and 'upper' are just outside > the range of y. > > John > > ------------------------- > Dr John Hillier > Senior Lecturer - Physical Geography > Loughborough University > 01509 223727 > > ________________________________________ > From: peter dalgaard <pda...@gmail.com> > Sent: 10 March 2016 17:49 > To: John Hillier > Cc: r-help@r-project.org > Subject: Re: [R] truncpareto() - doesn't like my data and odd error message > > Look closer.... > > -pd > > >> On 10 Mar 2016, at 18:41 , John Hillier <j.hill...@lboro.ac.uk> wrote: >> >> Thank you Peter, >> >> Yes, it seems to do the same even if I simultaneously make that change. >> Output below. >> >>> pdataH <- data.frame(y = H_to_fit$Height) >>> summary(pdataH) >> y >> Min. :2000 >> 1st Qu.:2281 >> Median :2666 >> Mean :2825 >> 3rd Qu.:3212 >> Max. :4794 >>> fit3 <- vglm(y ~ 1, truncpareto(1999, 4794), data = pdataH, trace = TRUE) >> Error in eval(expr, envir, enclos) : >> the value of argument 'upper' is too low (requires 'max(y) < upper') >> >> ------------------------- >> Dr John Hillier >> Senior Lecturer - Physical Geography >> Loughborough University >> 01509 223727 >> >> ________________________________________ >> From: peter dalgaard <pda...@gmail.com> >> Sent: 10 March 2016 09:36 >> To: John Hillier >> Cc: r-help@r-project.org >> Subject: Re: [R] truncpareto() - doesn't like my data and odd error message >> >> Also if you simultaneously change the 2000 to say 1999? >> >> -p >> >> On 10 Mar 2016, at 09:22 , John Hillier <j.hill...@lboro.ac.uk> wrote: >> >>> Thank you Peter, >>> >>> I believe this might be the way the error message is hard coded (i.e. it's >>> always y to describe the input). Anyway, I changed the first line to >>>> pdataH <- data.frame(y = H_to_fit$Height) >>> This makes the input 'y' instead of 'H_to_fit.Height', but makes no >>> difference to the outcome/error message. >>> >>> John >>> >>> ------------------------- >>> Dr John Hillier >>> Senior Lecturer - Physical Geography >>> Loughborough University >>> 01509 223727 >>> >>> ________________________________________ >>> From: peter dalgaard <pda...@gmail.com> >>> Sent: 09 March 2016 19:58 >>> To: John Hillier >>> Cc: r-help@r-project.org >>> Subject: Re: [R] truncpareto() - doesn't like my data and odd error message >>> >>>> On 09 Mar 2016, at 18:52 , John Hillier <j.hill...@lboro.ac.uk> wrote: >>>> >>>> Dear All, >>>> >>>> >>>> I am attempting to describe a distribution of height data. It appears >>>> roughly linear on a log-log plot, so Pareto seems sensible. However, the >>>> data are only reliable in a limited range (e.g. 2000 to 4800 m). So, I >>>> would like to fit a Pareto distribution to the reliable (i.e. truncated) >>>> section of the data. >>>> >>>> >>>> I found truncpareto(), and implemented one of its example uses >>>> successfully. Specifically, the third one at >>>> http://www.inside-r.org/packages/cran/vgam/docs/paretoff (also see p.s.). >>>> >>>> >>>> When I try to run my data, I get the output below. Inputs shown with >>>> chevrons. >>>> >>>> >>>>> pdataH <- data.frame(H_to_fit$Height) >>>>> summary(pdataH) >>>> H_to_fit.Height >>>> Min. :2000 >>>> 1st Qu.:2281 >>>> >>>> Median :2666 >>>> Mean :2825 >>>> 3rd Qu.:3212 >>>> Max. :4794 >>>>> fit3 <- vglm(y ~ 1, truncpareto(2000, 4794), data = pdataH, trace = TRUE) >>>> Error in eval(expr, envir, enclos) : >>>> the value of argument 'lower' is too high (requires '0 < lower < min(y)') >>>> >>>> >>>> This is odd as the usage format is - truncpareto(lower, upper), and >>>> varying 2000 to 1900 and 2100 makes no difference. Neither do smaller or >>>> larger variations. From the summary I think that my lowest input is 2000, >>>> which I am taking as min(y). I have also played with the upper limit. >>>> pdataH has 2117 observations in it. >>>> >>>> >>>> Is this a data format thing? i.e. of pdataH (a tried a few things, but to >>>> no avail) >>>> >>> >>> Umm, it doesn't seem to have a column called "y"? >>> >>> -- >>> Peter Dalgaard, Professor, >>> Center for Statistics, Copenhagen Business School >>> Solbjerg Plads 3, 2000 Frederiksberg, Denmark >>> Phone: (+45)38153501 >>> Office: A 4.23 >>> Email: pd....@cbs.dk Priv: pda...@gmail.com >>> >>> >>> >>> >>> >>> >>> >>> >>> >> >> -- >> Peter Dalgaard, Professor, >> Center for Statistics, Copenhagen Business School >> Solbjerg Plads 3, 2000 Frederiksberg, Denmark >> Phone: (+45)38153501 >> Office: A 4.23 >> Email: pd....@cbs.dk Priv: pda...@gmail.com >> > > -- > Peter Dalgaard, Professor, > Center for Statistics, Copenhagen Business School > Solbjerg Plads 3, 2000 Frederiksberg, Denmark > Phone: (+45)38153501 > Office: A 4.23 > Email: pd....@cbs.dk Priv: pda...@gmail.com > > > > > > > > > -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Office: A 4.23 Email: pd....@cbs.dk Priv: pda...@gmail.com ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
