Explore adding a scale/resolution facet to the interface

[karenmajewicz]

Sometimes sorting through search results in the geoportal can be complicated by the number of maps and data that appear in the list but that are for a vastly different scale/resolution than are of interest. For example, if you are looking for maps of a small town, it can be distracting to have hundreds of maps show up that intersect with the area but are of the state, country, or world. This project would examine possible ways to filter by the extent of the map (we have some preliminary scripts for this) or resolution (this would be harder...)

[karenmajewicz]

Potential DCAT field options:

• dcat:spatialResolutionInMeters
• dqv:QualityMeasurement - more general

I looked at a few different web semantic schemas, but have not found much support for traditional cartography equivalent scale type measurements (i.e. 1:1000).

[karenmajewicz]

The SDOH project has developed a custom field: sdoh_spatial_resolution_sm. Values can be:

• "County"
• "State"
• "Census Tract"
• "Census Block"
• "Census Block Group
• "Zip Code Tabulation Area (ZCTA)"

The also add the field spatial_resolution_note for free text comments on the resolution.

[karenmajewicz]

I am working on a script to extract and calculate some values. If a projection is provided with the dataset, I can estimate the following:

Test adding dcat:spatialResolutionInMeters. "Spatial Resolution is the average distance between consecutive vertices in the dataset's geometries for vector data, measured in meters. This value provides an estimate of the minimum spatial separation resolvable in the dataset, indicating the level of detail in the representation of geographic features. For raster data, spatial resolution corresponds to the pixel size, calculated from the dimensions of each pixel along the x and y axes, representing the ground distance covered by one pixel in meters."

Test adding Dublin Core Extent. Here is a field definition: "The extent represents the total geographic area covered by the dataset. For vector data, this is calculated as the sum of the areas of all geometries in the dataset, converted to square kilometers using an equal-area projection to ensure accuracy. For raster data, the extent is calculated based on the pixel size and the total number of pixels, resulting in the total area covered by the raster, expressed in square kilometers."

These fields will both hold numbers representing area calculations in meters (or kilometers?). We could bucket these numbers the way we do the Time Period facet. Then, we could either replace them with strings, like "State-sized" or provide a rollover explanation of the area range of the bucket.