[R-sig-Geo] Spatial filtering with glm with grid sampling

Sima Usvyatsov ghiaco at gmail.com
Thu Jan 11 17:53:27 CET 2018 

I had no idea this was coming up - can't believe it didn't come up in any
of my searches. Looks super useful, and I'm sure I'll be using it sooner
than later, whether on this analysis or not. The worked example is
ridiculously useful - so glad to have it.

If I'm reading the help page correctly (the autocorrelation bits,
struc(terms|group)) - to replicate the spatial autocorrelation within
Round, would I add this?

exp(site.Easting + site.Northing | RoundStart)

So something like this:

mod1 <- glmmTMB(Count ~ Stratum + SiteInStratum + ...other predictors +
# random variable
(1 | RoundStart) +
# autocorrelation
exp(site.Easting + site.Northing | RoundStart),

family = nbinom2, # or nbinom1 - I guess decide based on residuals?
correlation = corExp(form=~site.Easting + site.Northing + RoundStart)

Does that look like the twin of the glmmPQL specification I had (other than
family)? I can also email sig-ME if it's a better forum for this.

On Thu, Jan 11, 2018 at 8:33 AM, Roger Bivand <Roger.Bivand at nhh.no> wrote:

> On Thu, 11 Jan 2018, Sima Usvyatsov wrote:
>
> What other GLMM options do I have, under the restrictions of count data
>> with lots of zeroes and spatial autocorrelation? I was under the
>> impression
>> that glmmPQL was my only choice?
>>
>
> See for example:
>
> https://www.fromthebottomoftheheap.net/2017/05/04/compare-
> mgcv-with-glmmTMB/
>
> https://rjournal.github.io/archive/2017/RJ-2017-066/index.html
> (forthcoming)
>
> for surveys and discussions; maybe your current choice is the best bet for
> negbin.
>
>
> Roger
>
>
>> On Thu, Jan 11, 2018 at 8:18 AM, Roger Bivand <Roger.Bivand at nhh.no>
>> wrote:
>>
>> On Thu, 11 Jan 2018, Sima Usvyatsov wrote:
>>>
>>> Thank you so much for your response.
>>>
>>>>
>>>> Yes, I managed to muck up the fake data in 2 (!) ways - the 1,000 lons
>>>> and
>>>> the fact that the lon/lats weren't repeated. Here's the correct
>>>> structure.
>>>>
>>>> df <- data.frame(Loc = as.factor(rep(1:20, each = 5)), Lat =
>>>> rep(rnorm(20,
>>>> 30, 0.1), each = 5), Lon = rep(rnorm(20, -75, 1), each = 5), x =
>>>> rnegbin(100, 1, 1),
>>>> Stratum = rep(1:5, each = 20))
>>>>
>>>> In the meantime, I (somewhat) resolved the issue with the glmmPQL fixed
>>>> effects - my fault, of course.
>>>>
>>>> My current model is set up as follows:
>>>>
>>>> mod1 <- glmmPQL(Count ~ Stratum + SiteInStratum + ...other predictors,
>>>> random = ~ 1 |RoundStart,
>>>> family = quasipoisson,
>>>> correlation = corExp(form=~site.Easting + site.Northing + RoundStart)
>>>>
>>>> where RoundStart is the date/time of starting each count. I'm assuming
>>>> that
>>>> by "using a standard GLMM" you were thinking of MASS's glmmPQL()?
>>>> Does this look correct for specifying the full space/time dependence?
>>>> The
>>>> variogram and pacf look very decent, but one can never have too many
>>>> checks...
>>>>
>>>>
>>> I can't judge whether it really makes sense, but I think this is much
>>> more
>>> robust. I'd explore some other GLMMs too, to see what they contribute.
>>>
>>> Roger
>>>
>>>
>>>
>>> On Thu, Jan 11, 2018 at 5:01 AM, Roger Bivand <Roger.Bivand at nhh.no>
>>>> wrote:
>>>>
>>>> On Wed, 10 Jan 2018, Sima Usvyatsov wrote:
>>>>
>>>>>
>>>>> Hello,
>>>>>
>>>>>
>>>>>> I am running a negative binomial model (MASS) on count data collected
>>>>>> on a
>>>>>> grid. The dataset is large - ~4,000 points, with many predictors.
>>>>>> Being
>>>>>> counts, there are a lot of zeroes. All data are collected on a grid
>>>>>> with
>>>>>> 20
>>>>>> points, with high spatial autocorrelation.
>>>>>>
>>>>>> I would like to filter out the spatial autocorrelation. My question
>>>>>> is:
>>>>>> since I have very limited spatial info (only 20 distinct spatial
>>>>>> locations), is it possible to simplify ME() so that I don't have to
>>>>>> run
>>>>>> it
>>>>>> on the whole dataset? When I try to run ME() on a 100-point subset of
>>>>>> the
>>>>>> data, I get error in glm.fit: NA/NaN/Inf in 'x'. When I run it on a
>>>>>> single
>>>>>> instance of the grid, I "get away" with a warning ("algorithm did not
>>>>>> converge").
>>>>>>
>>>>>> Here's a fake dataset. It was grinding for a while but not throwing
>>>>>> errors
>>>>>> (like my original data would). Regardless, it demonstrates the
>>>>>> repeated
>>>>>> sampling at the same points and the large number of zeroes.
>>>>>>
>>>>>>
>>>>>> The data set has 1000 values in Lon, so is probably bigger than you
>>>>> intended, and when 100 is used is not autocorrelated. You seem to have
>>>>> a
>>>>> hierarchical model, with repeated measurements at the locations, so a
>>>>> multi-level treatment of some kind may be sensible. If you want to stay
>>>>> with ME-based spatial filtering, maybe look at the literature on
>>>>> spatial
>>>>> panel (repeated measurements are in time) with ME/SF, and on network
>>>>> autocorrelation (dyadic relationships with autocorrelation among
>>>>> origins
>>>>> and/or destinations). Both these cases use Kronecker products on the
>>>>> selected eigenvectors, I think.
>>>>>
>>>>> Alternatively, use a standard GLMM with a grouped iid random effect
>>>>> and/or
>>>>> a spatially structured random effect at the 20 location level. If the
>>>>> groups are repeated observations in time, you should model the whole
>>>>> (non-)separable space-time process.
>>>>>
>>>>> Hope this helps,
>>>>>
>>>>> Roger
>>>>>
>>>>>
>>>>> Any advice would be most welcome.
>>>>>
>>>>>>
>>>>>> library(spdep)
>>>>>> library(MASS)
>>>>>>
>>>>>> df <- data.frame(Loc = as.factor(rep(1:20, each = 5)), Lat =
>>>>>> rnorm(100,
>>>>>> 30,
>>>>>> 0.1), Lon = rnorm(1000, -75, 1), x = rnegbin(100, 1, 1))
>>>>>> coordinates(df) <- ~Lon + Lat
>>>>>> proj4string(df) <- CRS("+proj=longlat +ellps=WGS84 +datum=WGS84
>>>>>> +no_defs")
>>>>>> nb <- dnearneigh(x=coordinates(df), d1=0, d2=200,longlat = TRUE)
>>>>>> dists <- nbdists(nb, coordinates(df), longlat=TRUE)
>>>>>> glist <- lapply(dists, function(x) 1/x)
>>>>>> lw <- nb2listw(nb, glist,
>>>>>> <https://maps.google.com/?q=tw(nb,+glist,&entry=gmail&source=g>
>>>>>> style="W")
>>>>>> me <- ME(x ~ 1, data = df, family = "quasipoisson", listw = lw, alpha
>>>>>> =
>>>>>> 0.5)
>>>>>>
>>>>>>         [[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
>>>>>>
>>>>>>
>>>>>> --
>>>>>>
>>>>> Roger Bivand
>>>>> Department of Economics, Norwegian School of Economics,
>>>>> Helleveien 30, N-5045 Bergen, Norway.
>>>>> voice: +47 55 95 93 55; e-mail: Roger.Bivand at nhh.no
>>>>> Editor-in-Chief of The R Journal, https://journal.r-project.org/
>>>>> index.html
>>>>> http://orcid.org/0000-0003-2392-6140
>>>>> https://scholar.google.no/citations?user=AWeghB0AAAAJ&hl=en
>>>>>
>>>>>
>>>>>
>>>> --
>>> Roger Bivand
>>> Department of Economics, Norwegian School of Economics,
>>> Helleveien 30, N-5045 Bergen, Norway.
>>> voice: +47 55 95 93 55; e-mail: Roger.Bivand at nhh.no
>>> Editor-in-Chief of The R Journal, https://journal.r-project.org/
>>> index.html
>>> http://orcid.org/0000-0003-2392-6140
>>> https://scholar.google.no/citations?user=AWeghB0AAAAJ&hl=en
>>>
>>>
>>
> --
> Roger Bivand
> Department of Economics, Norwegian School of Economics,
> Helleveien 30, N-5045 Bergen, Norway.
> voice: +47 55 95 93 55; e-mail: Roger.Bivand at nhh.no
> Editor-in-Chief of The R Journal, https://journal.r-project.org/index.html
> http://orcid.org/0000-0003-2392-6140
> https://scholar.google.no/citations?user=AWeghB0AAAAJ&hl=en
>

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