Provide guidance for how agencies should designate Geospatial data

[gbinal]

Since the 'geospatial' filter for data.gov pretty much drives what ends up on geoplatform.gov's data catalog, there's a need to enable agencies to trigger that.

This is a related but distinct issue from representing FGDC metadata in the schema and is more a question of simply how to trigger that flag.

[philipashlock]

Since the use of the spatial field is already required for all geospatial datasets, Kishore has proposed that any dataset where this field has been populated could be considered geospatial.

[torrin47]

That's a reasonable suggestion, but the specification (and ISO) allows "(4) a geographic feature from the GeoNames database." Would the GeoPlatform handle that gracefully?

The EPA's metadata catalog requires bounding boxes on all records, including non-geo ones, which default to the US extent.

What about adopting a standard keyword to denote geo records?

[mhogeweg]

most geospatial datasets will use a bounding box instead of a name to indicate the (spatial) extent of the dataset/service. since Data.gov harvests the vast majority of its content from existing agency catalogs that already have FGDC/ISO metadata, it would be preferred if the Data.gov catalog uses the existing elements in metadata to conclude if the data is to be considered spatial or not.

[smrgeoinfo]

I agree with Marten that looking for a bounding box makes the most sense, but there is a problem when systems default to some regional (US extent) or global (-90,-180, 90, 180) bounding box when its not specified. For the NGDS we try to get a keyword 'non-geographic' added to explicitly indicate resources that do not have a geospatial footprint. Unless there is some explicit indication, telling resources that have a meaningful extent from resources that really aren't associated with a specific location is a very difficult problem.

[gbinal]

It seems like there may not be a clear way of tying a metadata field from Project Open Data to whether FGDC wants to consider a dataset 'geospatial'. The status quo seems to be working, if imperfect, so there may not be a consensus to change this now.

[bsweezy]

It seems like there is a potential difference between two interpretations of "geospatial" in this conversation: (1) dataset contains attributes which describe location, (2) dataset is suitable to be included on geospatial.gov. It seems to me that (2) is a subset of (1). It would be confusing to try to handle both scenarios with one field, especially since providers may be unfamiliar with what is included on (2).

Ideally, our navigation/aggregator/inventory software could look at the actual data and make a "guess" about its geospatialness.

[gbinal]

I think that I may have been taking a solution and going in search of a problem. I'm inclined to close this issue for now.

[kvuppala]

@gbinal @philipashlock
this is still open and there is no way of marking a particular dataset as geospatial in the data.json files, some agencies and community/topic POCs have this question once in a while. how should we handle approach this?

[webmaven]

Is there any documentation or guidance on what distinguishes (2) from (1)?

[mhogeweg]

I would not go and try build a reasoning engine that reads the data and then decides whether it's Geospatial or not. There are two things imho:

• if the data.json has a footprint the data set should be discoverable using the spatial filter.
• if the data has a location attribute it is a spatial data set and it will also have a footprint (the tools agencies use to manage spatial data all generate such footprint automagically and insert it in their spatial metadata formats already).

[webmaven]

Ah, spatial footprint (associated with the set) vs. spatial data (associated with the rows), is a useful distinction.

An edge case occurs to me: If a set consists of multiple files, each of which has it's own different footprint (not location), a consolidated file will then have a footprint associated with each row. Would you consider the original unconsolidated set (which probably has a footprint that consists of a union of footprints of it's contained sets) to just have a footprint, or spatial data as well?

[mhogeweg]

One can have great discussions on this.. But mostly it comes down to doing what's practical and what makes common sense.

After all: What is the extent of a point data set? The points? A convex hull around the points or a bounding box? As long as our monitors and paper are rectangular people typically use a minimum bounding box.

Each state in the us has their own county data sets (an arbitrary example), then there are national county data sets that combine all in one. If both types are considered spatial data, I would consider the collection of state county data sets also a spatial data set.