[R] truncpareto() - doesn't like my data and odd error message

[peter dalgaard]

Also if you simultaneously change the 2000 to say 1999?

-p

On 10 Mar 2016, at 09:22 , John Hillier <J.Hillier at 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$Height)
> This makes the input 'y' instead of 'H_to_fit.Height', but makes no difference to the outcome/error message.
> 
> John
> 
> -------------------------
> Dr John Hillier
> Senior Lecturer - Physical Geography
> Loughborough University
> 01509 223727
> 
> ________________________________________
> From: peter dalgaard <pdalgd at gmail.com>
> Sent: 09 March 2016 19:58
> To: John Hillier
> Cc: r-help at r-project.org
> Subject: Re: [R] truncpareto() - doesn't like my data and odd error message
> 
>> On 09 Mar 2016, at 18:52 , John Hillier <J.Hillier at lboro.ac.uk> wrote:
>> 
>> Dear All,
>> 
>> 
>> I am attempting to describe a distribution of height data.  It appears roughly linear on a log-log plot, so Pareto seems sensible.  However, the data are only reliable in a limited range (e.g. 2000 to 4800 m). So, I would like to fit a Pareto distribution to the reliable (i.e. truncated) section of the data.
>> 
>> 
>> I found truncpareto(), and implemented one of its example uses successfully.  Specifically, the third one at http://www.inside-r.org/packages/cran/vgam/docs/paretoff (also see p.s.).
>> 
>> 
>> When I try to run my data, I get the output below. Inputs shown with chevrons.
>> 
>> 
>>> pdataH <- data.frame(H_to_fit$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.mes at cbs.dk  Priv: PDalgd at 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.mes at cbs.dk  Priv: PDalgd at gmail.com