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      Layer Data Stats

      Intterra’s Layers Menu includes the Layer Stats Tool that provides users with the ability to extract basic stats from a map layer for a specific area of interest (AOI). 

      The tool fills a need for an emergency manager completing a FEMA FMAG application, ops planning an evacuation, a PIO pulling together numbers for a press release, a prevention specialist needing specific information about values at risk and more.

      NEW! You can now use an existing layer boundary, in addition to the drawing a 'lasso' area, to establish an area for stats calculations!

      Videos:

      Overview

      Expanding on the popular wildfire ‘lasso’ tools used for generating preformatted incident summaries and home risk reports, this tool provides users the flexibility to choose the best map layer and data attribute to answer the question being asked.  You can draw a lasso for an AOI or simply use the map view extent and return a count or total value. 
       The Layer Stats Tool is available on specific layers as determined by the client's point of contract. 
       There are three query types currently available -
      • Total Count - returns the total count of features for the selected sublayer. Example - Count of building footprints to get # of structures.
      • Sum of Feature Values -  returns the sum (total) for a numeric data field of your choice for the selected layer. Example - sum of a population field a Demographics sublayer to determine the population to be evacuated, sum of assessed value from parcel data.
      • Grouped Feature Count - returns the total count of features for the selected sublayer grouped by a data field of your choice. Example - Count of structure points grouped by a structure type field - # of residence, # of commercial, # of agricultural, etc.
      NOTE:  Depending on the selected Layer, and the data available within that layer, the Sum and Count options may not be available.

      Steps 

      To access the tool - 
      1. With the Layers Menu open, determine the layer that you need stats for.
      2. Click on the V icon to the right of the layer name to open Stats, Details, and view the sublayers.
      3. Click on STATS.
       To config the stats - 
      1. If not already highlighted blue, click on the Beaker icon to configure the analytics.
      2. Select a Sublayer from the dropdown list to perform your stats on (if only 1 sublayer is available, it will be defaulted for you). 
      3. Select the Query Type from the dropdown.
      4. If Sum of Feature Values or Grouped Feature Count, select a Data Field.
      5. Click on Submit to return results for the current map view extent
      6. View the results. Grab a screen shot and/or Copy and paste into a document as needed.
       To refine your results to a specific Area of Interest - 
       

      There are two options

      1. Draw an area using Lasso
        1. Select the 'Lasso' tool.
        2. Click on Draw.
        3. Draw the area of interest.
        4. View the results.  Grab a screen shot and/or Copy and paste into a document as needed.  From here, you can draw new boundaries, go back the the stats config and chose new stats, or go select another layer to do stats on. 
      2. Use an existing Map Polygon (NEW!)
        1. Select the 'Map' tool.
        2. Click on Select.
        3. Click on the map
        4. Select the map polygon feature to use
        5. View the results.   

      Important Considerations

      • The tool offers considerable user flexibility, but that requires some thought and understanding of the data that is being queried, especially for finding the correct Data Field for Sum of Feature Values or Grouped Feature Count queries and understanding data gaps and quality. To help understand the data
        • Selecting features on the map and viewing the info pane lets users see the data fields and related populated or missing values. 
        • Copy and pasting the layer source (link to the layer source doc - tbd) into a browser often provides much more detail. 
      • When selecting a line or polygon sublayer, the results include the entire feature(s) that intersects the lasso or map extent.  For example, a sum of population from Demographics (EJSCREEN) will return the population for the entire polygon, not just the portion within the users AOI.
       Limitations
      Layers - the tool will not work with the following file formats: kml/kmz, raster/grid or and user added layers.

      Here are few tips for use:

      • Wait to 'submit' your query until you have defined your area of interest using the lasso or selecting a boundary.  Submitting on the define query tab queries the entire area of your screen.

      • When using boundaries to define your area of interest, avoid large or complex features with many vertices.  

      • For determining population for larger urban populated areas, consider using the EJScreen layer for the Stats - using sum and select the field that you want.  This is not a good option for small query areas or in areas in rural populations.

       More...