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Human legal review of the upstream rights chain is required.","Do not assert a redistribution right until the Infochimps-to-dwyl rights chain has been reviewed by a human.","Dialect or scope: unspecified"],"redistribution_status":"pending","source_class":"broad-orthographic-list","source_id":"dwyl-english-words","source_version":"git:8179fe68775df3f553ef19520db065228e65d1d3","url":"https://raw.githubusercontent.com/dwyl/english-words/8179fe68775df3f553ef19520db065228e65d1d3/words_alpha.txt"},{"artifact_sha256":"d3fbe8485022088fcf527edcde2fbdc18b4bbc141ac58123c9adb462e086eaf7","attribution":"ENABLE (Enhanced North American Benchmark Lexicon); exact reuse terms are pending legal review","establishes":["source-membership","surface-spelling-as-listed"],"legal_review_status":"pending","licence_name":"Licence terms not stated by the source","licence_url":"https://www.wordgamedictionary.com/enable/","limitations":["The downloaded artifact is content-pinned by SHA-256, but it contains no licence notice and the configured source page does not state reuse terms.","The artifact is reproducibly pinned but no affirmative reuse grant has been located; redistribution approval remains pending.","Dialect or scope: North-American-oriented; exact edition metadata unavailable"],"redistribution_status":"pending","source_class":"historical-game-word-list","source_id":"enable","source_version":"artifact-sha256:d3fbe8485022088fcf527edcde2fbdc18b4bbc141ac58123c9adb462e086eaf7","url":"https://www.wordgamedictionary.com/enable/download/enable.txt"},{"artifact_sha256":"ee2d83651fbb91642bbed2bd30ead404c2cfbdfece01dacf284af6ea47795811","attribution":"first20hours/google-10000-english, derived from the Google Web Trillion Word Corpus and Peter Norvig's compilation","establishes":["source-membership","source-order"],"legal_review_status":"pending","licence_name":"No explicit licence grant in pinned repository metadata","licence_url":"https://raw.githubusercontent.com/first20hours/google-10000-english/bdf4c221bc120b0b7f6c3f1eff1cc1abb975f8d8/LICENSE.md","limitations":["The exact pinned LICENSE.md describes provenance but contains no explicit public-domain dedication or licence grant. Human review is required.","The pinned repository documents provenance but does not supply an affirmative licence grant; do not describe it as public domain.","Dialect or scope: USA no-swears variant"],"redistribution_status":"pending","source_class":"ranked-web-corpus-derived-list","source_id":"google-10000-english","source_version":"git:bdf4c221bc120b0b7f6c3f1eff1cc1abb975f8d8","url":"https://raw.githubusercontent.com/first20hours/google-10000-english/bdf4c221bc120b0b7f6c3f1eff1cc1abb975f8d8/google-10000-english-usa-no-swears.txt"},{"artifact_sha256":"5351ff405b1126ef555791dd4d9798a48e3e9a501a9fc481a9da957752cfb458","attribution":"FrequencyWords content derived from OpenSubtitles, licensed CC BY-SA 4.0","establishes":["source-token-observation","source-token-count"],"legal_review_status":"pending","licence_name":"CC BY-SA 4.0 (content)","licence_url":"https://raw.githubusercontent.com/hermitdave/FrequencyWords/525f9b560de45753a5ea01069454e72e9aa541c6/README.md","limitations":["The exact pinned README states MIT for code and CC BY-SA 4.0 for content. Human review is required for attribution and ShareAlike obligations on compiled and derived data.","Content is declared CC BY-SA 4.0. Attribution and ShareAlike treatment of the compiled frequency evidence and derived tiers require human approval.","Dialect or scope: unspecified"],"redistribution_status":"pending","source_class":"subtitle-derived-token-frequency","source_id":"frequencywords-en-2018","source_version":"git:525f9b560de45753a5ea01069454e72e9aa541c6; corpus-release:2018","url":"https://raw.githubusercontent.com/hermitdave/FrequencyWords/525f9b560de45753a5ea01069454e72e9aa541c6/content/2018/en/en_50k.txt"},{"artifact_sha256":"81917843c7f44ce2b094ac63873c2c7a4cf802040792c455ba3ca406891c3d22","attribution":"CMU Pronouncing Dictionary, Copyright 1993-2015 Carnegie Mellon University, BSD-2-Clause","establishes":["source-membership","arpabet-pronunciation-variant"],"legal_review_status":"pending","licence_name":"BSD-2-Clause","licence_url":"https://raw.githubusercontent.com/cmusphinx/cmudict/74790861f652b15e4ac49015a90074ad62a27690/LICENSE","limitations":["The exact pinned commit includes BSD-2-Clause redistribution terms. Human approval of the production attribution and binary-distribution obligations is still required.","BSD-2-Clause terms are present at the pin; retain copyright and licence notices. Production approval remains a recorded human decision.","Dialect or scope: primarily North American English"],"redistribution_status":"pending","source_class":"pronunciation-dictionary","source_id":"cmudict","source_version":"git:74790861f652b15e4ac49015a90074ad62a27690","url":"https://raw.githubusercontent.com/cmusphinx/cmudict/74790861f652b15e4ac49015a90074ad62a27690/cmudict.dict"},{"artifact_sha256":"ef70bc128a3ae67c23c5a4e31ec6b0ef3780e94881faa3adf9b73c2f7f684b4d","attribution":"The Word Index first-party content-safety exclusion policy","establishes":["content_filter","search_results","result_counts"],"legal_review_status":"pending","licence_name":"Reuse terms not yet approved","licence_url":null,"limitations":["This bounded policy list cannot determine whether every usage is offensive or benign."],"redistribution_status":"pending","source_class":"first-party-content-safety-policy","source_id":"offensive-term-policy","source_version":"2026.07-review-pending.2","url":"/about/data"}],"study_build_id":"cbbdba7067eaa6317e060c5795ae8c7db9b641eea209d5ef5825773634508b5e","study_id":"study.spelling-difficulty","study_version":"1.0.1","tables":[{"caption":"The exact population used by this version of the analysis.","column_ids":["stage","record_count"],"dataset_id":"study.spelling-difficulty.population","heading":"Population and exclusions","note":null,"row_ids":["raw","policy-excluded","safe","analysis"],"table_id":"study.spelling-difficulty.population-table"},{"caption":"Every value derives from the declared integer scoring formula.","column_ids":["metric","record_count","denominator","share_percent","score_value"],"dataset_id":"study.spelling-difficulty.summary","heading":"Headline formula-score results","note":null,"row_ids":["covered-tier-1-2","tier-1-2-at-least-6","highest-tier-1-2-score","highest-all-score"],"table_id":"study.spelling-difficulty.summary-table"},{"caption":"Bands partition the integer score; tier cohorts are build-specific ranking bands, not usage claims.","column_ids":["band","score_range","all_record_count","all_share_percent","common_record_count","common_share_percent"],"dataset_id":"study.spelling-difficulty.bands","heading":"Formula-score bands by ranking cohort","note":null,"row_ids":["band-0","band-1-2","band-3-5","band-6-9","band-10-plus"],"table_id":"study.spelling-difficulty.bands-table"},{"caption":"The scan is deterministic: longest declared grapheme wins per position.","column_ids":["grapheme","weight","record_count","share_percent"],"dataset_id":"study.spelling-difficulty.graphemes","heading":"Declared vowel graphemes and their prevalence","note":null,"row_ids":["grapheme-ae","grapheme-aigh","grapheme-augh","grapheme-ea","grapheme-eau","grapheme-ei","grapheme-eigh","grapheme-eou","grapheme-ie","grapheme-ieu","grapheme-igh","grapheme-iou","grapheme-oe","grapheme-ou","grapheme-ough","grapheme-ue","grapheme-ui"],"table_id":"study.spelling-difficulty.grapheme-table"},{"caption":"A computed exemplar limited to 20 rows; ties break alphabetically.","column_ids":["rank","spelling","length","phoneme_count","letters_per_phoneme","letter_phoneme_count_surplus","vowel_sequence_points","doubled_letter_count","formula_score"],"dataset_id":"study.spelling-difficulty.highest-scoring-tier-1-2","heading":"Highest-scoring tier 1-2 spellings","note":null,"row_ids":["rank-1","rank-2","rank-3","rank-4","rank-5","rank-6","rank-7","rank-8","rank-9","rank-10","rank-11","rank-12","rank-13","rank-14","rank-15","rank-16","rank-17","rank-18","rank-19","rank-20"],"table_id":"study.spelling-difficulty.exemplar-table"}],"title":"Declared spelling-form score: a reproducible three-component formula","transformation_steps":[{"description":"Compare normalized letter counts with the primary retained variant's phoneme count; each surplus letter contributes three declared points.","deterministic":true,"limitations":["A count surplus cannot identify silent letters or align individual letters to phonemes."],"transformation_id":"spelling-difficulty.surplus-v1"},{"description":"Scan each spelling left to right against the declared vowel-sequence list, longest sequence first, summing declared weights.","deterministic":true,"limitations":["The scan counts spelling shapes only; it does not verify each grapheme's pronunciation."],"transformation_id":"spelling-difficulty.grapheme-scan-v1"},{"description":"Count adjacent identical letter pairs; each pair contributes two declared points.","deterministic":true,"limitations":[],"transformation_id":"spelling-difficulty.doubling-v1"},{"description":"Partition total formula scores into five declared numeric bands and rank the tier 1-2 exemplar by score with alphabetical tie-breaks, limited to 20 rows.","deterministic":true,"limitations":["Band boundaries are declared editorial cut points on an integer scale."],"transformation_id":"spelling-difficulty.banding-v1"}],"update_history":[{"data_version":"2026.07-lexical.4","effective_date":"2026-07-19","result_sha256":"adc8445a55a61610b21469db2ed536e3cefe2c9e88918eaf0393117ac084bc1c","review_status":"machine-validated","reviewer":null,"study_version":"1.0.0","summary":"Initial reproducible heuristic difficulty release."},{"data_version":"2026.07-lexical.5","effective_date":"2026-07-25","result_sha256":"adc8445a55a61610b21469db2ed536e3cefe2c9e88918eaf0393117ac084bc1c","review_status":"machine-validated","reviewer":null,"study_version":"1.0.0","summary":"Rebound byte-identical results to the 2026.07-lexical.5 data release; no numeric changes."},{"data_version":"2026.07-lexical.6","effective_date":"2026-07-26","result_sha256":"adc8445a55a61610b21469db2ed536e3cefe2c9e88918eaf0393117ac084bc1c","review_status":"machine-validated","reviewer":null,"study_version":"1.0.0","summary":"Rebound byte-identical results to the 2026.07-lexical.6 data release; no numeric changes."},{"data_version":"2026.07-lexical.6","effective_date":"2026-08-01","result_sha256":"1b87194a7f3663f2b5ca7ee6b94144f819f8cb6255d4a16bfa295dc50e567151","review_status":"machine-validated","reviewer":null,"study_version":"1.0.1","summary":"Reframed the output as an unvalidated declared formula score, renamed its fields and bands, and limited instructional claims."}],"user_relevance":"Shows exactly how the declared formula ranks tier 1-2 spellings in this build; the score is an audit and exploration measure, not validated spelling difficulty or teaching guidance."}