[STATSGRASS] kriging results not within range of original data

[Carlos "Guâno" Grohmann]

Hello,

I'm dong some kriging of SRTM data, and noted that the kriged results
don't lie within the range of the original data. It is not too far
from the original, but there is a difference.

original dem:

Data attributes:
     band1
 Min.   : 634.0
 1st Qu.: 759.0
 Median : 814.0
 Mean   : 856.5
 3rd Qu.: 923.0
 Max.   :1312.0

resampled dem:
   var1.pred
 Min.   : 633.2
 1st Qu.: 759.2
 Median : 814.3
 Mean   : 856.4
 3rd Qu.: 923.5
 Max.   :1307.4


I konw thatt small deviations from the values range can occur, but I
was looking for some deeper explanation on this. If someone could
point me out any literature I can refer to, I will be thankful.

Carlos

-- 
+-----------------------------------------------------------+
              Carlos Henrique Grohmann - Guano
  Geologist M.Sc  - Doctorate Student at IGc-USP - Brazil
Linux User #89721  - carlos dot grohmann at gmail dot com
+-----------------------------------------------------------+
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