RFT App

Relational frame

The comparison frame

Relating stimuli along a graded dimension: more, less, bigger.

What it looks like

Comparison is asymmetric in a way coordination is not. If A is bigger than B, the entailed relation is not that B is bigger than A but that B is smaller than A. The relation reverses rather than repeating.

Combinatorial entailment is strong and transitive: A bigger than B, B bigger than C, therefore A bigger than C, and C smaller than A.

Worked example

A learner is taught that coin A buys more than coin B, and that coin B buys more than coin C.

Without further teaching they derive that A buys more than C, and that C buys least of the three. Transformation of function follows: if buying more is currently valuable, A becomes the preferred coin even though its physical size may be smallest.

How to build a lesson for this frame

  1. Use a single dimension

    Fix one comparative dimension per lesson: size, quantity, or speed. Do not vary the dimension inside a trial block.

  2. Train adjacent pairs

    Teach A-to-B and B-to-C explicitly, both directions, so that the reversal is in repertoire before you probe.

  3. Probe transitivity

    Test the A-to-C relation and its reverse. This is the derived relation the lesson exists to produce.

  4. Probe function transfer

    Attach a function to one end of the scale and test whether preference reorganises across the untrained members.

Common pitfalls

Letting physical magnitude co-vary with the trained relation is the classic confound: if the bigger-valued item is also the physically larger picture, you have taught a non-arbitrary discrimination, not a relational frame. Randomise physical properties against the arbitrary relation.

Build a comparison lesson

Draft the trial structure in RFT App, then edit it into the program you actually want.

See how it works

Other relational frames

Coordination

Relating stimuli as the same or equivalent. The basis of naming.

Distinction

Relating stimuli as different, without specifying how.

Opposition

Relating stimuli as opposites along a shared dimension.

Hierarchical

Relating stimuli as member and category, part and whole.

Common questions

What is a comparison frame?
A relational frame that relates stimuli along a graded dimension such as more, less, bigger, or faster.
Why is comparison harder than coordination?
Because the entailed relation reverses rather than repeats. If A is bigger than B, the derived relation is that B is smaller than A, which requires tracking direction as well as relation.