Defining layer and class weights

Layer and class weights are defined as part of the model to indicate the level of importance the layer and the classes within it have in relation to the project you are planning. Weights are assigned to layers by defining a percentage for each one to be included in the model. The percentage assigned to a model indicates the amount of weight it will have in the analysis.

The classes provide a way to give weight to different types of information represented by the layer. For instance, you can assign the Critical Habitat layer 40 percent for the analysis and assign the Noncritical Habitat and Critical Habitat classes different weight values.

Next to each class, you can view its cell value range. The range includes the lowest value and is exclusive of the highest value for the classification field. This value indicates the field values that correlate with each layer's class.

Some of the data that you will see in Landscape Modeler contains NoData values. When one layer in an analysis contains NoData values, the output from the analysis will also contain NoData values in the same location, regardless of whether other layers included in the analysis also have NoData values at the same location. The best way to determine where NoData values exist in one or more of your input layers is to use the Preview button on the Select Layers panel. Areas that are completely transparent are areas where the pixel values are NoData. You can still use the slider to reclassify the NoData values.

Note:

Reclassifying the NoData values does not affect the output analysis. These areas will still be considered NoData, regardless of the reclassification value applied.

Steps:

1. If necessary, sign in to Landscape Modeler by doing the following:
   1. Start a web browser and open the Landscape Modeler page.

      A sign-in page appears.

   2. Type your user name in the Username text box.
   3. Type your password in the Password text box.
   4. Click Sign In.
2. If necessary, click Select Layers.

   The Select Layers properties appear.

3. Check the check boxes next to the layers to be included in the model and uncheck the check boxes next to the layers to be excluded in the model.
4. Click the Design Model tab.
5. Type percent values in the text boxes to the right of each layer name.

   The percentages must total 100 percent or the model cannot run.

6. Click the arrow to the left of the layer name to view the classes.
7. Type a weight value in the text box or use the slider to indicate the weight for each class and press the Tab key.
8. Repeat steps 5 and 6 for each layer with weights to be defined.
9. Click Run Model to see the results.