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issues with krige function

4 messages · Adrienne Wootten, ONKELINX, Thierry

#
Greetings all,

Ran into a strange problem with the krige function from geoR.  The
problem that I am having is that while the krige function seems to
work well, the resulting predicted values are all NAs.  Given the size
of the datasets I am working with can't attach it, but I can provide
snippets of the datasets.
station year month day  obs         mpe        bias type      lat       lon
140  319147 2011     8  28 0.00 0.000000000  0.00000000 COOP 35.48667 -82.96833
141  319354 2011     8  28 0.02 0.001305799 -0.01869420 COOP 34.25722 -78.68722
142  319357 2011     8  28 0.00 0.045194085  0.04519409 COOP 34.40944 -78.79139
143  319440 2011     8  28 6.92 5.530313974 -1.38968603 COOP 35.85278 -77.03056
144  319461 2011     8  28 0.98 0.949224103 -0.03077590 COOP 34.14250 -77.87861
145  319467 2011     8  28 0.30 1.492852601  1.19285260 COOP 34.32083 -77.92056
146  319476 2011     8  28 2.95 3.284362345  0.33436235 COOP 35.69389 -77.94556
147  319555 2011     8  28 0.00 0.000000000  0.00000000 COOP 36.13083 -81.22750
148  319667 2011     8  28 0.00 0.014472943  0.01447294 COOP 35.85583 -80.36083
149  319675 2011     8  28 0.00 0.000000000  0.00000000 COOP 36.13056 -80.54806
[using ordinary kriging]
lon      lat var1.pred var1.var
1  -86.28771 33.91335       NaN      NaN
2  -86.27388 33.94722       NaN      NaN
3  -86.26003 33.98111       NaN      NaN
4  -86.24615 34.01500       NaN      NaN
5  -86.23225 34.04890       NaN      NaN
6  -86.21835 34.08280       NaN      NaN
7  -86.20441 34.11672       NaN      NaN
8  -86.19045 34.15064       NaN      NaN
9  -86.17648 34.18457       NaN      NaN
10 -86.16249 34.21851       NaN      NaN
lon              lat                 var1.pred        var1.var
 Min.   :-86.29   Min.   :30.51   Min.   : NA     Min.   : NA
 1st Qu.:-82.38   1st Qu.:33.73   1st Qu.: NA     1st Qu.: NA
 Median :-79.88   Median :35.22   Median : NA     Median : NA
 Mean   :-79.91   Mean   :35.26   Mean   :NaN     Mean   :NaN
 3rd Qu.:-77.48   3rd Qu.:36.76   3rd Qu.: NA     3rd Qu.: NA
 Max.   :-73.16   Max.   :40.16   Max.   : NA     Max.   : NA
                                               NA's   :44408   NA's   :44408


Any ideas are greatly appreciated, I'm not getting any warnings or
errors from krige, so this is perplexing to me.
#
My apologies to all, the package is gstat that I am using not geoR.
thanks!
A
On Tue, Oct 30, 2012 at 1:35 PM, Adrienne Wootten <amwootte at ncsu.edu> wrote:

  
    
#
Dear Adrienne,

What is the output of summary(casestudy) and summary(gridmeta)?

What happens if you set nmax to 10?
krige(formula=bias~1,locations=~lon+lat,data=casedata,newdata=gridmeta ,model=v.fit, nmax = 10)

ir. Thierry Onkelinx
Instituut voor natuur- en bosonderzoek / Research Institute for Nature and Forest
team Biometrie & Kwaliteitszorg / team Biometrics & Quality Assurance
Kliniekstraat 25
1070 Anderlecht
Belgium
+ 32 2 525 02 51
+ 32 54 43 61 85
Thierry.Onkelinx at inbo.be
www.inbo.be

To call in the statistician after the experiment is done may be no more than asking him to perform a post-mortem examination: he may be able to say what the experiment died of.
~ Sir Ronald Aylmer Fisher

The plural of anecdote is not data.
~ Roger Brinner

The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data.
~ John Tukey


-----Oorspronkelijk bericht-----
Van: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] Namens Adrienne Wootten
Verzonden: dinsdag 30 oktober 2012 18:36
Aan: r-help at r-project.org
Onderwerp: [R] issues with krige function

Greetings all,

Ran into a strange problem with the krige function from geoR.  The problem that I am having is that while the krige function seems to work well, the resulting predicted values are all NAs.  Given the size of the datasets I am working with can't attach it, but I can provide snippets of the datasets.
station year month day  obs         mpe        bias type      lat       lon
140  319147 2011     8  28 0.00 0.000000000  0.00000000 COOP 35.48667 -82.96833
141  319354 2011     8  28 0.02 0.001305799 -0.01869420 COOP 34.25722 -78.68722
142  319357 2011     8  28 0.00 0.045194085  0.04519409 COOP 34.40944 -78.79139
143  319440 2011     8  28 6.92 5.530313974 -1.38968603 COOP 35.85278 -77.03056
144  319461 2011     8  28 0.98 0.949224103 -0.03077590 COOP 34.14250 -77.87861
145  319467 2011     8  28 0.30 1.492852601  1.19285260 COOP 34.32083 -77.92056
146  319476 2011     8  28 2.95 3.284362345  0.33436235 COOP 35.69389 -77.94556
147  319555 2011     8  28 0.00 0.000000000  0.00000000 COOP 36.13083 -81.22750
148  319667 2011     8  28 0.00 0.014472943  0.01447294 COOP 35.85583 -80.36083
149  319675 2011     8  28 0.00 0.000000000  0.00000000 COOP 36.13056 -80.54806
[using ordinary kriging]
lon      lat var1.pred var1.var
1  -86.28771 33.91335       NaN      NaN
2  -86.27388 33.94722       NaN      NaN
3  -86.26003 33.98111       NaN      NaN
4  -86.24615 34.01500       NaN      NaN
5  -86.23225 34.04890       NaN      NaN
6  -86.21835 34.08280       NaN      NaN
7  -86.20441 34.11672       NaN      NaN
8  -86.19045 34.15064       NaN      NaN
9  -86.17648 34.18457       NaN      NaN
10 -86.16249 34.21851       NaN      NaN
lon              lat                 var1.pred        var1.var
 Min.   :-86.29   Min.   :30.51   Min.   : NA     Min.   : NA
 1st Qu.:-82.38   1st Qu.:33.73   1st Qu.: NA     1st Qu.: NA
 Median :-79.88   Median :35.22   Median : NA     Median : NA
 Mean   :-79.91   Mean   :35.26   Mean   :NaN     Mean   :NaN
 3rd Qu.:-77.48   3rd Qu.:36.76   3rd Qu.: NA     3rd Qu.: NA
 Max.   :-73.16   Max.   :40.16   Max.   : NA     Max.   : NA
                                               NA's   :44408   NA's   :44408


Any ideas are greatly appreciated, I'm not getting any warnings or errors from krige, so this is perplexing to me.

--
Adrienne Wootten
Graduate Research Assistant
State Climate Office of North Carolina
Department of Marine, Earth and Atmospheric Sciences North Carolina State University

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#
Thierry, To answer your first question

summary(casedata)
   station               year          month        day          obs
           mpe
 Length:236         Min.   :2011   Min.   :8   Min.   :28   Min.
:0.0000   Min.   :0.00000
 Class :character   1st Qu.:2011   1st Qu.:8   1st Qu.:28   1st
Qu.:0.0000   1st Qu.:0.00000
 Mode  :character   Median :2011   Median :8   Median :28   Median
:0.0000   Median :0.00000
                    Mean   :2011   Mean   :8   Mean   :28   Mean
:0.6119   Mean   :0.60163
                    3rd Qu.:2011   3rd Qu.:8   3rd Qu.:28   3rd
Qu.:0.0225   3rd Qu.:0.03953
                    Max.   :2011   Max.   :8   Max.   :28   Max.
:9.3600   Max.   :9.05766
      bias              type                lat             lon
     city
 Min.   :-4.75583   Length:236         Min.   :33.53   Min.   :-84.84
 Length:236
 1st Qu.: 0.00000   Class :character   1st Qu.:34.37   1st Qu.:-82.71
 Class :character
 Median : 0.00000   Mode  :character   Median :35.06   Median :-81.18
 Mode  :character
 Mean   :-0.01028      Mean   :35.18   Mean   :-81.00
 3rd Qu.: 0.00000        3rd Qu.:35.99   3rd Qu.:-79.37
 Max.   : 2.82117          Max.   :36.98   Max.   :-76.33
    state            preciptime
 Length:236         Length:236
 Class :character   Class :character
 Mode  :character   Mode  :character
lon              lat            xcell             ycell
     row              col
 Min.   :-86.29   Min.   :30.51   Min.   :1895112   Min.   :-6545105
Min.   :  1.00   Min.   :  1.0
 1st Qu.:-82.38   1st Qu.:33.73   1st Qu.:2184464   1st Qu.:-6330770
1st Qu.: 61.75   1st Qu.: 46.0
 Median :-79.88   Median :35.22   Median :2473816   Median :-6114053
Median :122.50   Median : 91.5
 Mean   :-79.91   Mean   :35.26   Mean   :2473816   Mean   :-6114053
Mean   :122.50   Mean   : 91.5
 3rd Qu.:-77.48   3rd Qu.:36.76   3rd Qu.:2763169   3rd Qu.:-5897337
3rd Qu.:183.25   3rd Qu.:137.0
 Max.   :-73.16   Max.   :40.16   Max.   :3052521   Max.   :-5683002
Max.   :244.00   Max.   :182.0


To answer your second question, I'm not quite sure why, but apparently
constraining nmax like that was exactly what it needed, because now it
is producing values.
v.fit = vgm(psill=1.2914,model="Mat",range=14.1611,nugget=0.23,kappa=83.1047)
krige.pred.out =
krige(formula=bias~1,locations=~lon+lat,data=casedata,newdata=gridmeta,model=v.fit)
summary(krige.pred.out)

      lon              lat                 var1.pred         var1.var
 Min.   :-86.29   Min.   :30.51   Min.   :-1.083   Min.   :0.253
 1st Qu.:-82.38   1st Qu.:33.73   1st Qu.:-0.044   1st Qu.:0.253
 Median :-79.88   Median :35.22   Median : 0.000   Median :0.253
 Mean   :-79.91   Mean   :35.26   Mean   :-0.051   Mean   :0.253
 3rd Qu.:-77.48   3rd Qu.:36.76   3rd Qu.: 0.000   3rd Qu.:0.253
 Max.   :-73.16   Max.   :40.16   Max.   : 1.252   Max.   :0.254
                                               NA's   :14925    NA's   :31483

Thanks for the help.

Adrienne


On Wed, Oct 31, 2012 at 10:28 AM, ONKELINX, Thierry
<Thierry.ONKELINX at inbo.be> wrote: