Ratio
Definition
Proportional relationship between the heights of small letters, capitals and ascenders/descenders.
- Field
- Handwriting examination
- Measures
- Proportion between letter zones
- Zones compared
- Small letters, capitals, ascenders/descenders
- Use
- Individualising or class trait in a writing sample
Common questions
Why do examiners compare letter-height ratio rather than absolute letter size?+
Absolute size varies with the writing surface, pen, and even mood or posture, but the proportion between a writer's small-letter, capital, and ascender/descender heights tends to stay more consistent across different writing instances, making the ratio a more reliable comparison point.
Can ratio alone identify a writer?+
No single measurement like ratio is used in isolation. It is combined with other handwriting characteristics such as slant, spacing, pen pressure, and letter formation to build a fuller comparison between questioned and known writing.
Related terms
- ASTM E2290
- ASTM International standard guide for examination of handwritten items; lists the 21 discriminating elements that the examiner reports on.
- Baseline
- The imaginary line on which letters rest; can be straight, ascending, descending, convex, concave or undulating.
- Class Characteristic
- A feature shared by an entire group of objects (every shoe of one model has the same sole tread; every tire of...
- Exemplar (Standard)
- Authentic specimen writing of the suspect used for comparison. Two classes: request (taken under examiner control) and collected (pre-existing genuine writings).
- Handwriting
- A neuromuscular act in which graphic forms are produced on a surface; the product of motor memory built up through years of...
- 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...
- Pen Lift and Hiatus
- Pen lift is a deliberate stop and re-start within or between letters; hiatus is a gap left in a stroke that should...
- Retrace
- Re-tracing of a stroke back over its original path, common in letters like d, t and lower-loop closures.
- Slant
- Angle of letters relative to the baseline (right-slant, vertical, left-slant). A habit-driven class plus individual feature.