Figure Weights asks which figure will balance a scale
In the WAIS Figure Weights subtest, the person examines the types and numbers of shapes on balanced scales and chooses the option that would balance another scale within the time limit. Identical shapes are treated as having equal weight, and the missing weight must be derived from the equality between the two sides.
In the Japanese WAIS-IV, Figure Weights is a supplemental Perceptual Reasoning Index, or PRI, subtest used for ages 16–69. PRI is ordinarily calculated from the core subtests Block Design, Matrix Reasoning, and Visual Puzzles. A Japanese WAIS-IV report can therefore include a Figure Weights scaled score even when that score was not used to calculate PRI or FSIQ.
Figure Weights became a primary fluid-reasoning subtest in the 2024 US WAIS-5
In the 2024 US WAIS-5, the former WAIS-IV PRI is replaced by separate Visual Spatial and Fluid Reasoning indexes. Figure Weights is a primary Fluid Reasoning Index, or FRI, subtest alongside Matrix Reasoning and is also used to calculate FSIQ.
The US WAIS-5 also uses Figure Weights with Arithmetic to calculate the Quantitative Reasoning Index, or QRI, and includes Figure Weights in the Expanded Fluid Index. Although the task presents a visual balance scale, its current US role emphasizes solving unfamiliar problems through quantitative relationships.
WAIS-IV and WAIS-5 compared explains the wider change in indexes and subtest roles.
Figure Weights requires quantitative reasoning across several equivalence conditions
The person must translate the balance-scale diagrams into quantitative relationships:
- understand that a balanced scale represents equal weight on both sides;
- treat shapes with the same form and color as equal weights;
- identify substitution relationships among shapes across several scales;
- combine the available conditions to derive the quantity needed in the missing position; and
- select the option that satisfies all the conditions.
This is not a calculation problem in which numbers are inserted into a familiar formula. The central demand is to discover the quantitative relationship from the figures and apply it to another scale.
Time affects performance, but Figure Weights is not a Processing Speed Index subtest. It examines quantitative fluid reasoning, or Gf, under a time limit.
What higher and lower Figure Weights scores can show
In the Japanese WAIS-IV, a higher scaled score indicates that, compared with people of the same age, the person was strong at treating figures as quantities and deriving an unknown relationship from several equivalences. Even without an equation being provided, they could organize the visual conditions and apply the same relationship to a new scale.
A lower score means that greater demand arose in matching the two sides, representing figures as quantities, retaining several conditions, selecting the relevant relationship, or choosing an answer within the time limit.
If Figure Weights is clearly higher than Matrix Reasoning, deriving a quantity from equivalence may be a relative strength compared with inducing a visual rule from changes among figures. If it is higher than Arithmetic, visual quantitative relationships may be easier to handle than retaining a spoken problem and calculating mentally. How to read WAIS results explains how to interpret these differences within the whole profile.
How Figure Weights differs from Matrix Reasoning and Arithmetic
| Subtest | How information is presented | Direct task |
|---|---|---|
| Figure Weights | Balance scales and figures | Derive an unknown quantity from equivalence |
| Matrix Reasoning | A matrix or sequence of figures | Discover a rule from spatial arrangements and changes |
| Arithmetic | A spoken quantitative problem | Retain the problem, translate its relationships into an operation, and calculate mentally |
WAIS and BrainTypeIQ use related Figure Weights formats with separate scoring
BrainTypeIQ Figure Weights also asks the person to identify weight relationships among figures on balanced scales and choose the figure needed in a missing position. In both tasks, shapes with the same form and color represent the same weight, and several conditions may need to be combined to derive an unknown relationship.
BrainTypeIQ uses its own items, online administration, timing, scoring, and comparison norms. This makes Figure Weights a strong quantitative-reasoning task within BrainTypeIQ's Gf domain and five-domain cognitive profile without treating it as the same subtest or score as WAIS Figure Weights.