— Cognitive science

Floor Effect

Term

test floor

Domain

Cognitive psychology

First introduced

20th century

IQ relevance

Direct

Floor Effect (test floor) refers to the inability of a test to discriminate among very low scorers. The concept is central to modern cognitive psychology and psychometrics — particularly to how IQ is theorized, measured, and interpreted.

What floor effect actually means

In cognitive psychology, floor effect is operationalized as the inability of a test to discriminate among very low scorers. It is distinct from related constructs in that it specifically captures a distinct, measurable aspect of cognitive function.

How it's measured

Measured through standardized testing batteries and laboratory paradigms specific to the construct.

Relationship to IQ

Floor Effect is integrated into the broader theory of IQ and cognitive function. It contributes to and is partially measured by composite IQ scores.

Test your floor effect and 5 other cognitive axes

Core Brain's 20-minute test decomposes IQ into six cognitive components so you see your specific profile.

Why this matters

Understanding floor effect is foundational for anyone trying to interpret an IQ score meaningfully. The single composite IQ number conceals significant variation across cognitive functions; understanding the components is how you go from "I scored 130" to "I scored 130, with particular strength in [X] and relative weakness in [Y]."

Frequently asked

What is floor effect?

Floor Effect (test floor) refers to the inability of a test to discriminate among very low scorers. It is a central concept in cognitive psychology and IQ measurement.

How is floor effect different from general IQ?

Composite IQ is a weighted aggregate of multiple cognitive abilities. Floor Effect is one specific component or property that contributes to but is not identical to the IQ score.

Can floor effect be improved?

Generally limited room for improvement in trait-level cognitive properties; significant variability in measured performance day-to-day.