Cross Validation (Geostatisical Analyst)
サマリ
Removes one data location and then predicts the associated data using the data at the rest of the locations. The primary use for this tool is to compare the predicted value to the observed value in order to obtain useful information about some of your model parameters.
使用法
When using this tool in Python, the result object contains both a feature class and a CrossValidationResult, which has the following properties;
- Count—Total number of samples used.
- Mean Error—The averaged difference between the measured and the predicted values.
- Root Mean Square Error—Indicates how closely your model predicts the measured values. The smaller this error, the better.
- Average Standard Error—The average of the prediction standard errors.
- Mean Standardized Error—
- Root Mean Square Standardized Error—This should be close to one if the prediction standard errors are valid. If the root-mean-squared standardized error is greater than one, you are underestimating the variability in your predictions. If the root mean square standardized error is less than one, you are overestimating the variability in your predictions.
The fields in the optional output feature class are described in GA Layer To Points.
構文
CrossValidation_ga (in_geostat_layer, {out_point_feature_class})
パラメータ | 説明 | データ タイプ |
in_geostat_layer |
The geostatistical layer to be analyzed. | Geostatistical Layer |
out_point_feature_class (オプション) |
Stores the cross-validation statistics at each location in the geostatistical layer. | Feature Class |
コードのサンプル
CrossValidation example 1 (Python window)
Perform cross validation on an input geostatistical layer.
import arcpy arcpy.env.workspace = "C:/gapyexamples/data" cvResult = arcpy.CrossValidation_ga("C:/gapyexamples/data/kriging.lyr") print "Root Mean Square error = " + str(cvResult.rootMeanSquare)
CrossValidation example 2 (stand-alone script)
Perform cross validation on an input geostatistical layer.
# Name: CrossValidation_Example_02.py # Description: Perform cross validation on an input geostatistical layer. # Requirements: Geostatistical Analyst Extension # Import system modules import arcpy # Set environment settings arcpy.env.workspace = "C:/gapyexamples/data" # Set local variables inLayer = "C:/gapyexamples/data/kriging.lyr" # Check out the ArcGIS Geostatistical Analyst extension license arcpy.CheckOutExtension("GeoStats") # Execute CrossValidation cvResult = arcpy.CrossValidation_ga(inLayer) print "Root Mean Square error = " + str(cvResult.rootMeanSquare)
関連項目
ライセンス情報
ArcView: 必須 Geostatistical Analyst
ArcEditor: 必須 Geostatistical Analyst
ArcInfo: 必須 Geostatistical Analyst
7/10/2012