topic Re: Filled contours grid legend class values doesn't show up all class in the map in ArcGIS GeoStatistical Analyst Questions

Filled contours grid legend class values doesn't show up all class in the map

TahirTamba1 — Thu, 25 Sep 2014 15:08:51 GMT

Hi all,

I made a interpolation of contaminated soil data using ordinary kriging but the result of the grid prediction does not match the values displayed by the legend from the minimum value 0.023 to the maximum value 0.99 %. This values represent the measured variable (ratio of the volumes of area of contaminated soil).
For cons, I noticed that the values showned in the legend correspond to the measured values for the interpolation grid generated from the ordinary kriging, not the predicted values. I think the outline grid should reflect the predicted values?
If this is not the case, why the last two classes of the legend (measured values do not appear on the map).

However, when I convert the grid contour to raster map all the values of the map legend are represesented with the corresponding predicted values with a little difference from the last classe of the data range values. The max predicted values from the cross validation indicated a value less high than the one showned in the raster legend. Why?

See attached files of two maps below

Thank you to enlighten me on these issues.

Regards

Re: Filled contours grid legend class values doesn't show up all class in the map

EricKrause — Thu, 25 Sep 2014 22:15:14 GMT

Hi Tahir,

Please read this topic, as it explains the differences between the classification of geostatistical layers and rasters:

kriging results to raster

Quick summary: The classification of geostatistical layers is based on the values of the field that was used in the interpolation. After converting to raster, the classifications are based on the histogram of the raster.

Let me know if anything still is not clear.

Re: Filled contours grid legend class values doesn't show up all class in the map

TahirTamba1 — Fri, 26 Sep 2014 14:51:00 GMT

Hello Eric,

Thank you for answering to my question and for pointing me out to the right resources regarding this issue. I also read the document before that the explanations provided into this arereally clear. The explanation provided in the document helps to clarify the confusion about the difference observed between the results of the GA grid layer and raster.
However, my first question was related to the difference between the displayed ranges in the legend and the grid itself. On the first map, the legend displayed includes 10 ranges between the min and max values in the grid but only the first eight classes are displayed. But I got my answer linked is: http://support.esri.com/en/knowledgebase/techarticles/detail/25648.

Thank you again for allowing me to clarify this issue.