← All proof trees · WILLIAM MCKINLEY SCHOOL

1. 1
   What you seeWithheld by the publisher

   The publisher suppressed this cell (too few students to report). The site stores it as suppressed and never as zero.

   vs. peers

   —

   vs. citywide

   —

   unit

   percent

   direction

   higher is better

2. 2
   How it was computedvalue = published '% proficient or advanced' (accountability cohort by default)

   1. Unzip the district's PSSA/Keystone archive and read the accountability-cohort ('Acct') and all-tested ('Actual') school CSVs.
   2. Keep rows for the test, subject, grade, and subgroup this metric represents.
   3. Store the published '% proficient or advanced' as the value and the published number tested as the denominator; suppressed cells (asterisks/blanks) are stored as suppressed, not zero.
   4. Store the accountability-cohort cut as the default (population_cut = 'acct') and the all-tested cut alongside it ('actual').

   Note: stored percentiles are computed by a batch script after loads; a difference from the live reconstruction means a newer load changed the comparison set and the batch has not been re-run.

   Evidence: metric tree: 3rd grade ELA proficiency (PSSA)

3. 3
   The stored cellThe stored cell

   table

   philly_school_year_metrics

   value

   null

   denominator

   15

   suppressed

   true

   citywide_percentile

   null

   comparison_group_percentile

   null

   source_load_id

   96e07ea5-c26b-4f50-acf8-e159bd17d2e0

   Evidence: data model overview

4. 4
   The load that wrote itWritten on 2026-06-04 by sdp_pssa_keystone_2023-24.ts

   source id

   sdp_pssa_keystone_2023-24

   file URL

   https://cdn.philasd.org/offices/performance/Open_Data/School_Performance/PSSA_Keystone/2023_2024_PSSA_Keystone_All_Data.zip

   SHA-256 of the file read

   d89570e75caa9d30bd32f41de7a654b1df298e1a27a8bf6538f6dc4a6cfa9261Copy hash

   bytes

   802,929

   year covered

   2023-24

   code commit

   de835926d57d5e04d34ef3f4666df5b66fa57672

   To confirm you have the same file: download it from the URL above, then run shasum -a 256 <downloaded file> Copy command — the output should equal the hash above. If the publisher has since replaced the file, the hashes will differ, which is itself useful to know.

   Evidence: loader script · first-fetch findings for this file · source registry

5. 5
   The publisher's filePSSA & Keystone results, 2023-24

   School District of Philadelphia (Performance Office). Same structure as the 2024-25 file, one year earlier.

   format

   ZIP of CSVs

   join key

   id_eos (= ULCS Code)

   landing page

   https://opendataphilly.org/datasets/sdp-pssa-keystone-performance/

   • Same as the 2024-25 file.
6. 6
   How it was checkedChecks: 2 passed, 2 flagged

   • ✓ passedBase case: served cells vs an independent re-read of the ingested file
   • ✓ passedCompleteness: every source cell is served
   • ⚠ flaggedAccountability-cohort vs all-tested files are byte-identical after sorting in SDP's 2024-25 archive — a publisher defect, so this check cannot distinguish the two populations
   • ⚠ flaggedCross-publisher sanity check vs the state's Keystone results

   Checked at ±1: 0 mismatches, 0 cells served but absent from the file, 0 in the file but not served (ALL, acct, latest year).

   Evidence: Base case · Completeness · Accountability-cohort vs all-tested files are byte-identical after sorting in SDP's 2024-25 archive — a publisher defect, so this check cannot distinguish the two populations · Cross-publisher sanity check vs the state's Keystone results

7. 7
   Assumptions & caveatsAssumptions and caveats

   • The accountability cohort (students enrolled for the full year) is the intended canonical population. However, the two files SDP publishes for 2024-25 ('Acct' and 'Actual') are identical once sorted — 28,525 rows with no differing value or denominator — so the served 'acct' and 'actual' cuts carry the same numbers. We treat this as a publisher defect (one file published under two names) and cannot say which population the numbers describe.

   • District-run and alternative schools only from this file; charter schools' Keystone results come from the state's Future Ready file.

   Algorithms involved: Citywide and peer-group percentiles, Peer groups: 40 nearest neighbors on demographics