Allograph
Definition
The abstract mental representation of a letter form. Different people may share the same allograph (from copybook training) but execute it with different motor programmes.
- Level of representation
- Abstract, mental letter form
- Origin
- Copybook or school training
- Contrasted with
- Motor execution (individual handwriting)
- Field
- Forensic document examination
Common questions
If two writers share the same allograph, does that mean their handwriting looks identical?+
No, the allograph is only the shared template both learned in school; the actual pen movements, pressure, and proportions that produce it vary by writer and are what document examiners compare, not the underlying letter concept.
How does this concept explain individuality in handwriting?+
Because many writers start from the same taught allograph, similarity at that level carries little weight. Individuality emerges from how consistently a specific writer deviates from the copybook form, which is the class-versus-individual-characteristic distinction examiners rely on.
Related terms
- Ballistic Execution
- The phase of a motor stroke that runs to completion without real-time feedback correction. Ballistic strokes are the most consistent within a...
- CEDAR Study (Srihari 2002)
- The first large-scale statistical study of handwriting individuality; measured 512 micro-features across 1,500 writers and found inter-writer variability significantly exceeding intra-writer variability,...
- Class Characteristic
- A feature shared by an entire group of objects (every shoe of one model has the same sole tread; every tire of...
- Copybook System
- The institutionally taught handwriting model a writer was trained on in school: Palmer (US), Vere Foster (UK), Bharati Patrachari (India, Devanagari), Sutterlin/DIN...
- Individual Characteristic
- A characteristic unique to a specific typewriter unit arising from manufacturing variation or service wear; used to identify or eliminate a specific...
- Line Quality
- The overall fluency, rhythm and pressure variation of a stroke. Genuine writing has smooth, rhythmic, pressure-modulated lines; forgeries show tremor, blunt starts...
- Motor Programme
- The stored neuromuscular sequence that controls handwriting execution. Once stable in adulthood, it runs largely automatically, making handwriting consistent and individuating.
- Natural Variation
- The normal within-writer fluctuation in individual features across repetitions of the same letter or writing task; an examiner assesses whether questioned-writing variation...
- NIST 2020 Handwriting Report
- The National Institute of Standards and Technology's evaluation of forensic handwriting examination and human factors; confirmed examiner accuracy above chance but identified...