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NYCPlanning / db-pluto

🔭 PLUTO and MapPLUTO
https://nycplanning.github.io/db-pluto
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Research: change historic district update to use district file, not lot-based file #344

Open AmandaDoyle opened 2 years ago

AmandaDoyle commented 2 years ago

LS request: LPC data - change historic district update to use district file, not lot-based file

What would the implications be of changing the LPC source data from lpc_historic_districts: LPC Individual Landmark and Historic District Building Database to lpc_historic_district_areas: Historic Districts

How will the results change in PLUTO? What logic would need to change?

Dig into previous issues because AD remembers debating this at length and coming to a decision.

Oysters1874 commented 2 years ago

By comparing the spatial join results using the new area-based file (lpc_historic_district_areas) and the results of the original lot-based file, we observed several changes that may lead to further concerns.

Firstly, the new area-based file cannot capture the information of individual landmark. If using the new file to assign BBL with a historic district, some individual landmarks will be assigned to a particular district, which shouldn't be the case.

Secondly, there are some overlapped historical districts, such as there are 2 polygons of Carnegie Hill Historic District located within the polygon of the larger Expanded Carnegie Hill Historic District. Also, both "Central Park West-West 73rd - 74th Street Historic District" and "Central Park West-76th Street Historic District" are located within the larger "Upper West Side/Central Park West Historic District". Therefore, if we are switching to the new area-based dataset, we need extra steps to limit the scope when assigning BBLs with historic districts. Probably, just assign them with the smaller geometry.

Thirdly, by manually checking, there are 2 BBLs are switching from West 71st Street Historic District to West End-Collegiate Historic District Extension. Both of them are locating on the boundary of two districts. By eyeballing, they do belong to the latter, which means the new area-based file is correct in terms of this. Not sure whether there is any error in the lot-based file, lpc_historic_districts.

Also, the naming of historic districts are incoherent between the two files in terms of spelling, plural/single form, whitespaces near punctuations, etc. If we are using the area-based file, it may be necessary to make the naming coherent in order to keep track of changes.

Oysters1874 commented 2 years ago
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