I have a question regarding the directory tree for Weekly Places Patterns. As for Weekly Places Patterns (for data from 2020-06-15 to 2020-11-30), I thought the corresponding weeks are 2020-06-24, 2020-07-01, and etc. at the first glance, but it turns out the starting date in 2020/06/24/16/patterns-part1.csv.gz is 2020-06-15. Therefore, what is actual meaning for the tree-like directory structure (e.g., 2020/06/24/16/)?
This looks like this is part of the old release - Firstly, I recommend using the Weekly Places Patterns Backfill for Dec 2020 and Onward Release instead as it covers the same time period in 2020 but using the most up-to-date POI and geometry information from Dec 2020.
In general, we have a Weekly Patterns product which is released every Wednesday (6/24, 7/1, etc.) and covers the previous Mon-Sun week. This is why the file which was then-delivered on 6/24 covers 6/15-6/21 in terms of data. The Weekly Places Patterns (for data from 2020-11-30 to Present) dataset will follow this Wednesday file structure as well, except for the on one or two rare occasions files get delivered Thursdays.
However, since we are constantly making updates to things like geometries and POIs, this means more recent months have the benefit of these changes. To propogate those changes into our historical data, every 6 months we will hindcast all of the historical Patterns data using the most up-to-date changes. This is what we call a “backfill”, and the most recent backfill was done in Dec 2020. So for datasets which have “backfill” in the title, the file paths will indeed start on the Monday (e.g., 6/15, 6/22, etc).
In short, the file to which you’re referring was delivered on the Wednesday schedule, but I recommend you use the backfill data for the same period instead since it is the most up-to-date, and there the file paths will be the Mondays as expected.