Platform Layer: Foundation

LUCADictionary, The Foundation of Phoneme-Level Precision

LUCADictionary is a comprehensive database of 763,000+ grapheme-phoneme mappings that powers LUCA's phoneme-level speech recognition. Identification at the sound level, not just the word level.

Validated By:
NSF SBIRCarnegie MellonU.S. Patent

What is a Letter-Sound Mapping Database?

A letter-sound mapping database (also called a grapheme-phoneme mapping database) connects written letters (graphemes) to their spoken sounds (phonemes). LUCADictionary connects written symbols to their spoken sounds across the full complexity of English spelling, from simple consonants to complex vowel teams and Latin/Greek roots.

Ehri (2014) Research Foundation
The Precision Gap

Why Do Most Reading Tools Fall Short?

Word-level tools detect errors but can't identify them. They know a word is wrong but not why, leaving teachers guessing about which skill gaps to address.

Comparison: Reading "Ship" as "Sip"

Standard Word-Level Tools

Marks the word as incorrect. Full stop. No data on whether it was a speed error or a systematic digraph confusion.

LUCA + LUCADictionary

Identifies the specific /sh/ → /s/ substitution. Signals a clear skill gap in consonant digraph recognition that triggers targeted instruction.

Linguistic Depth

Grapheme Coverage

Every letter and combination encountered, simple consonants to complex vowel teams.

Context-Aware

Positional variations: the "c" in "cat" differs from "c" in "city". Exact phonetic modeling.

Sight Words

All Dolch and Fry sight words are fully mapped and integrated into the skill-identification layer.

Morphology

Prefixes, suffixes, and Latin/Greek roots mapped systematically for advanced word study.

Built on Peer-Reviewed Rigor

CredentialImpact
Carnegie Mellon PartnershipArchitecture developed with CMU's AI program for technical rigor.
NSF ValidationNSF SBIR funding (3% acceptance) validates innovation and impact.
Patent ProtectionU.S. Patent No. 12,394,332 B2 protects LUCA's mapping technology.
Ehri (2014) AlignmentBuilt to support orthographic mapping, mapping graphemes to phonemes.

Dictionary FAQ

Frequently Asked Questions

A grapheme is a letter combination that represents a sound; a phoneme is the sound itself. Mapping connects written symbols to spoken sounds. LUCADictionary contains 763,000+ of these, ensuring precision for any word a student reads.

Standard dictionaries define meanings. LUCADictionary maps the sound structure, connecting letters to sounds at the phoneme level. This is linguistic intelligence for skill identification, not just vocabulary lookup.

Word-level tools tell you a student missed a word but not why. Phoneme-level assessment reveals the pattern (e.g., /sh/ digraph confusion) that should guide intervention. NSF-funded research shows this detects 40% more errors.

Dyslexic readers often have specific sound substitutions that word-level tools miss. LUCADictionary identifies these patterns, ensuring intervention targets the actual skill gaps aligned with IDA best practices.

Yes. It supports orthographic mapping (Ehri, 2014) and was validated through NSF SBIR funding and built in collaboration with Carnegie Mellon researchers's AI program.

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