Midnumbers

Midnumbers are numbers that lie at the exact midpoint between two reference values on a numeric scale. The term is used in several disciplines to denote a central, neutral, or baseline value. In mathematics, a midnumber for endpoints a and b (a ≤ b) is m = (a + b) / 2. If one considers a finite set S, the set of midnumbers consists of all values that can be expressed as (x + y) / 2 with x, y in S. In metric spaces this generalizes to the midpoint between two points.

In measurement and data analysis, midnumbers align with the idea of a neutral point on a scale, such as the central value on a Likert-type survey (for example, 3 on a 1–5 scale). They are not statistical summaries like the median, but rather fixed central reference points determined by the scale endpoints. Midnumbers can be used in interpolation, calibration, and contexts such as color or audio signal processing where a linear blend is desired.

Characteristics of midnumbers include being uniquely determined by a pair of endpoints and preserving symmetry about the midpoint. On evenly spaced scales, midnumbers appear at regular half-step positions and provide a straightforward means of representing a central value without reference to the data distribution.

Applications of midnumbers span survey design, computer graphics (color interpolation via linear blending), digital audio (midpoint sampling), and numerical methods that employ linear interpolation. The term is descriptive rather than standardized and is often used interchangeably with notions of midpoint or neutral value in applied contexts.