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dssg / land-bank

Analytics tool to help the Cook County Land Bank acquire vacant and abandoned properties strategically.
http://dssg.io/projects#landbank
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Import USPS vacancy data #41

Closed tplagge closed 11 years ago

tplagge commented 11 years ago

I've downloaded and parsed the USPS vacancy data into CSV files. They live in /mnt/ebs/data/usps/*.cook.csv. Now they just need to be imported into the database.

tplagge commented 11 years ago

According to Sarah, the parcel-level vacancy data are pretty hairy. They actually drove around and looked at properties, and found that when they compared 311 vacancy, USPS vacancy, and on-the-ground data gathering, only the latter seemed reliable. For the USPS data, one of the sticky issues is that a property can be labeled vacant or no-stat even if it's not vacant in the sense that we care about--let's say the owner lives there part-time and has forwarded her mail to her permanent address, for example.

However, the aggregate data are definitely worth using, since it's fairly timely (quarterly release) and fairly reliable.

A key issue is the distinction between vacant address and no-stat addresses. In built-out neighborhoods, "vacant" generally means "between tenants" while "no-stat" means "boarded up and abandoned." In neighborhoods with construction activity, "no-stat" can mean "under construction." "Vacant" can also apply to vacation homes, which could be important along the lakefront near the Loop.

tplagge commented 11 years ago

...And just to further complicate things, comparison over time is complicated by the fact that the USPS has changed its methodology at least once. It's definitely a fair comparison between neighborhoods at a given time, but the time series for a given neighborhood may be more difficult to interpret.