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  • 1.  Census block IDs in LODES are inconsistent with the shapefiles provided by the U.S. Census Bureau

    Posted 06-09-2023 03:36 PM

    Hello,

    Sorry about posting a question on LODES here, but I do not know any other forums for census data use that I can post this question on. Please let me know if you know a better place where I can post this question. Thank you.

    I am currently using "ca_od_main_JT01_2019.csv", which is the main Origin-Destination file of Primary Jobs in 2019 for California. My concern is that some Census block IDs in LODES are inconsistent with the shapefiles provided by the U.S. Census Bureau at https://www.census.gov/geographies/mapping-files/time-series/geo/tiger-line-file.html. For example, there are census blocks whose IDs start with "06037265521" and "06037265522" in LODES, which cannot be found in the shapefiles provided by the U.S. Census Bureau. There are also census blocks whose IDs start with "06037265520" in the shapefiles provided by the U.S. Census Bureau, which cannot be found in LODES.
    I was wondering if there is a correspondence table that documents the inconsistency in census block IDs between LODES and the shapefiles provided by the U.S. Census Bureau.
    Thank you for your time.


  • 2.  RE: Census block IDs in LODES are inconsistent with the shapefiles provided by the U.S. Census Bureau

    Posted 06-09-2023 04:13 PM

    The Census Bureau puts out new versions of block boundary shapefiles with each annual TIGER/Line release. Maybe the LODES blocks use a different "vintage" of block definitions than the shapefile you're using? To my knowledge, there are very few official changes in block definitions between censuses, but there were a small number of county, tract & block group changes that could cause discrepancies in the IDs of blocks from one vintage to another, and blocks might get split as new boundaries are added to reflect changes in other larger areas. There are also many major changes between 2010 and 2020 block definitions.



  • 3.  RE: Census block IDs in LODES are inconsistent with the shapefiles provided by the U.S. Census Bureau

    Posted 06-09-2023 05:59 PM

    Hello Jonathan,

    Thank you so much for your reply. I just realized that the LODES file I downloaded is enumerated by 2020 census blocks, while the shapefiles from the census bureau are enumerated by the 2010 census blocks, which is the reason why there is inconsistency.