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At this point, you can see all of the violent crime locations, along with the half-mile school buffers, but much of the map is so densely covered with overlapping points that it becomes difficult to tell exactly how many points there are and to see the underlying school buffers. In addition, while you can see the spatial distribution of the points, you are not provided with any sort of useful summary of the data. Performing a spatial join will allow you to discover exactly how many violent crimes occurred within a half mile of each school in 2010.

The goal of performing a this spatial join is to add a numeric field to the end of the school buffer attribute table that tells you how many crime points are contained within each school buffer.

1. In the Contents pane, right-click the HISDElemSchools_HalfMileBuffer layer and select Joins and Relates > Spatial Join.

The Spatial Join tool will open within the Geoprocessing pane. For 'Target Features', the HISDElemSchools_HalfMileBuffer is already selected, since that is the layer from which you launched the tool.

1. For ‘Join Features’, use the drop-down box to select the HPDCrime2010_HISD layer.For ‘Merge Rule,’ use he drop-down menu to select Count.
2. For ‘Output Feature Class,’ rename the feature class from Join_Output to from HISDElemSchools_HalfMileBuff to “HISDElemSchools_HalfMileBuffer_WithCrimeStats".

The 'Field Map of Join Features' describes how the features will be summarized as they are joined. The first half of the list of fields displays the attributes of the school buffer layer, ending with the Shape_Area field. The second half of the list of fields, beginning with the Date field, displays the attributes of the crime layer. A count field showing how many crime points intersect with each half-mile buffer will automatically be provided, but, since many crimes will be appended to each school buffer, it does not make sense to generate summary statistics about the rest of the crime fields, since things like offense type, premise code, and address cannot be averaged. Therefore, you will remove the 

1. Ensure Ensure that your Spatial Join tool Parameters tab appears as shown below and click Run.

The new layer should appear at the top of your Contents pane. 

1. Right-click the In the Contents pane, right-click the new HISDElemSchools_HalfMileBuffer_WithCrimeStats layer and selectAttribute Table.

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