# Sinhala Dyslexic Writing Pattern Taxonomy

This document defines the interpretable dyslexic writing-pattern taxonomy used in this project.

The taxonomy is derived from surface-level orthographic and phonetic deviations observed in Sinhala dyslexic writing.

---

## 1. Orthographic Instability

**Definition:**  
Inconsistent or incorrect written forms of characters without strong phonetic substitution.

**Surface Signals:**

- Character omission
- Character addition
- Diacritic loss
- Inconsistent spelling

**Example:**

- Clean: රුපියල් දෙදාහක් තියෙනවා
- Dyslexic: රුපියල් දෙදාහක් තියනව

---

## 2. Phonetic Confusion

**Definition:**  
Errors that reflect confusion between phonologically similar sounds.

**Surface Signals:**

- Character substitution
- Phonetically similar replacements

**Example:**

- Clean: ගණිත
- Dyslexic: ගනිත

---

## 3. Word Boundary Confusion

**Definition:**  
Difficulty maintaining correct word segmentation.

**Surface Signals:**

- Word merges
- Extra spaces
- Missing spaces

---

## 4. Mixed Dyslexic Pattern

**Definition:**  
Presence of multiple dyslexic patterns within the same sentence or essay.

**Criteria:**

- More than one dominant surface error type

---

## 5. No Dominant Pattern

**Definition:**  
No consistent dyslexic pattern detected or very low error density.

---

## Notes

- Patterns are assigned using rule-based dominance logic.
- This system prioritizes explainability over raw accuracy.