Glossary of Terms

Common terms used in facial analysis and symmetry research.

Bilateral Symmetry

The property of being divisible into symmetrical halves on either side of a unique plane. In humans, the left and right sides of the face.

Fluctuating Asymmetry (FA)

Small, random deviations from perfect symmetry in bilaterally paired traits. Often used in biology as a measure of developmental stability.

Golden Ratio (Phi)

A mathematical ratio (approximately 1.618) often found in nature and art, historically associated with aesthetic beauty and ideal proportions.

Rule of Thirds

A guideline in composition and aesthetics where an image is divided into nine equal parts. In facial analysis, it refers to horizontal division of the face into forehead, nose, and chin sections.

Change Blindness

A perceptual phenomenon occurring when a change in a visual stimulus is introduced and the observer does not notice it. Our Face Flip tool leverages this to highlight asymmetry.

Mere Exposure Effect

A psychological phenomenon by which people tend to develop a preference for things merely because they are familiar with them. This explains why we prefer our mirror image over our photo image.