[R-sig-Geo] problem with enveloped test in spatstat

[Nicholas Bradley]

Good morning

I hope you are well

I have a question regarding the persp and perspPoints functions

I have the x and y spatial coordinates and also the altitude of all these
coordinates. However, despite consulting several manuals, I have as yet
been unable to create a terrain elevation plot and also to plot the points.
I have only managed to create a persp image showing density

I would therefore appreciate very much if anyone could be so kind as to help

Thank you very much

Kind regards

Nicholas

On 22 April 2018 at 08:46, David Unwin <ubfa915 at mail.bbk.ac.uk> wrote:

> Many thanks.  It is a superb book and amazing value for money.  My only
> excuse is that I have not as yet got to page 392.  Plotting the functions
> also makes it a lot clearer.
> Dave
>
> On 21 April 2018 at 22:50, Marcelino de la Cruz Rot <
> marcelino.delacruz at urjc.es> wrote:
>
> > Hi David,
> >
> > This is very clearly explained in page 393 of Baddeley et al. 2015.
> >
> > Basically, the MAD test is affected by transformations of the summary
> > function, with the L-function providing more powerful tests because of
> its
> > stabilization of the variance.
> >
> > If you are interested in point pattern analysis I would recommend you to
> > get a copy of this nice book.
> >
> >
> > Cheers,
> >
> > Marcelino
> >
> >
> > Adrian Baddeley, Ege Rubak, Rolf Turner (2015). Spatial Point Patterns:
> > Methodology and Applications with R. London: Chapman and
> >   Hall/CRC Press.
> > http://www.crcpress.com/Spatial-Point-Patterns-Methodology-
> > and-Applications-with-R/Baddeley-Rubak-Turner/9781482210200/
> >
> >
> >
> >
> >
> >
> > El 21/04/2018 a las 18:05, David Unwin escribió:
> >
> >> Can any *spatstat* user explain to me why the two p-values obtained
> below
> >> for an envelope test against CSR are so different?
> >>
> >>
> >>
> >> data(swedishpines)
> >>> d<-swedishpines
> >>> plot(d)
> >>> mad.test(d,Kest,nsim=999,verbose=F)
> >>>
> >>
> >>
> >>          Maximum absolute deviation test of CSR
> >>
> >>          Monte Carlo test based on 999 simulations
> >>
> >>          Summary function: K(r)
> >>
> >>          Reference function: theoretical
> >>
> >>          Alternative: two.sided
> >>
> >>          Interval of distance values: [0, 24] units (one unit = 0.1
> >> metres)
> >>
> >>          Test statistic: Maximum absolute deviation
> >>
> >>          Deviation = observed minus theoretical
> >>
> >>
> >>
> >> data:  d
> >>
> >> mad = 150.69, rank = 216, p-value = *0.216*
> >>
> >>
> >>
> >> mad.test(d,*Lest*,nsim=999,verbose=F)
> >>>
> >>
> >>
> >>          Maximum absolute deviation test of CSR
> >>
> >>          Monte Carlo test based on 999 simulations
> >>
> >>          Summary function: L(r)
> >>
> >>          Reference function: theoretical
> >>
> >>          Alternative: two.sided
> >>
> >>          Interval of distance values: [0, 24] units (one unit = 0.1
> >> metres)
> >>
> >>          Test statistic: Maximum absolute deviation
> >>
> >>          Deviation = observed minus theoretical
> >>
> >>
> >>
> >> data:  d
> >>
> >> mad = 2.9921, rank = 9, p-value = *0.009*
> >>
> >>
> >>
> >> *!!!*
> >>
> >>
> >>
> >> These data are dispersed relative to CSR:
> >>
> >> kl<-envelope(d,Kest,nsim=999,correction="border")
> >>> plot(kl)
> >>>
> >>
> >> Dave Unwin
> >>
> >>         [[alternative HTML version deleted]]
> >>
> >> _______________________________________________
> >> R-sig-Geo mailing list
> >> R-sig-Geo at r-project.org
> >> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
> >> .
> >>
> >>
> > --
> > Marcelino de la Cruz Rot
> > Depto. de Biología y Geología
> > Física y Química Inorgánica
> > Universidad Rey Juan Carlos
> > Móstoles España
> >
> >
>
>
> --
>
>
> David J. Unwin
> Professor Emeritus in Geography
> Birkbeck, University of London
> Phone  +44(0)1604 686526 Mobile: +44(0)7840 297239 (text preferred)
> SKYPE: david.unwin99
>
>         [[alternative HTML version deleted]]
>
> _______________________________________________
> R-sig-Geo mailing list
> R-sig-Geo at r-project.org
> https://stat.ethz.ch/mailman/listinfo/r-sig-geo
>



-- 
Kind regards

Nicholas Bradley

PhD Candidate
School of International Relations
University of St Andrews

	[[alternative HTML version deleted]]