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 WAIS-IV, Figure Weights is a supplemental subtest of the Perceptual Reasoning Index (PRI). In WAIS-5, it becomes a primary subtest of the Fluid Reasoning Index (FRI), contributes to FSIQ, and is used with Arithmetic for the Quantitative Reasoning Index.
The person must translate the balance diagrams into quantitative relationships:
- understand that a balanced scale represents equal weight on both sides;
- treat figures with the same shape 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.
The relationship must be discovered from the figures and applied to another scale. Figure Weights measures quantitative fluid reasoning under a time limit. WAIS-IV and WAIS-5 compared explains the wider change in subtest roles.
What higher and lower Figure Weights scores can show
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.
This kind of processing is involved in choosing a combination that must satisfy several constraints and applying a relationship established in one step to the next decision.
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, Arithmetic, and Set Relations
| Subtest | How information is presented | Direct task |
|---|---|---|
| Figure Weights | Balanced scales containing 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-5 Set Relations | Explicit relational conditions | Derive a conclusion that is consistent with all of them |
BrainTypeIQ uses a similar quantitative-reasoning task format
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, figures with the same shape and color represent the same weight, and several conditions may need to be combined to derive an unknown relationship.
WAIS and BrainTypeIQ are different assessments, with different scoring systems, standardization, and purposes, so their scores are not interchangeable.
BrainTypeIQ combines Figure Weights with Matrix Reasoning so its fluid-reasoning domain reflects both deriving an answer from stated equivalences and discovering a rule in unfamiliar figures.