US ACS variables defaulting to 2015-2015 (1 year) timespan

[michellemho]

Problem: When querying for data across the entire United States using the current DO UI, many null values are returned. This is because the DO UI defaults to the latest timespan measurement '2015 - 2015' (a 1-year ACS estimate) and there is not full geographic coverage across the US for 1-year estimates.

Solution:

The timespan needs to be specified in OBS_GetMeasure. The most recent 5-year estimate ('2011 - 2015') should be the default.

select obs_getmeasure(the_geom, 'us.census.acs.B01003001', 'none', 'us.census.tiger.county', '2011 - 2015');

[juanignaciosl]

@michellemho I've unassigned @ethervoid and added it to Backend/DO triage in order to address this as soon as we can. I think that it's not blocking because you can specify the timespan. You can check our board to see ongoing tasks.

[michellemho]

Okay! No problem. I didn't think this problem was blocking either, but it came up in the channel #data-obs-help again, so I just wanted to log it in Github.

[antoniocarlon]

The timespan-collection.js queries OBS_GetAvailableTimespans and orders the result using the timespan name (ORDER BY timespan_name DESC). We would need to order the timespans using the timespan weight (ORDER BY timespan_weight DESC).

Also, the timespan_weight is always NULL in the table obs_meta_timespan so it needs to be calculated (now it's explicitly set to NULL).

The solution could be making the timespan a "full right member" of the model (obs_timespan table?) and computing the timespan weights on the ETL. The timespan_weight could be added to the obs_meta_timespan table using an OUTER JOIN.

[alrocar]

👋