The competition-among-relations-in-nominals theory of conceptual combination: implications for stimulus class formation and class expansion.
Old pairings predict new learning speed, so script your teaching sets by relation history.
01Research in Context
What this study did
Taylor (2002) built a math-style theory called CARIN.
It says the more often a learner has seen two things linked before, the faster they will glue new things together.
The paper uses word pairs like 'mountain goat' to show how old links guide new learning.
What they found
The theory predicts exact numbers.
If a child has heard 'mountain' paired with 'goat' many times, they will quickly learn that 'mountain goat' is a new animal.
The same math works for ABA stimulus classes.
How this fits with other research
Weissman-Fogel et al. (2015) tested the idea with college students.
They first taught five extra conditional relations to one abstract shape.
Class formation jumped from a large share to a large share, matching CARIN's claim that richer relation history speeds learning.
Fields et al. (2012) added one meaningful picture to a class and saw the same boost.
Ayres-Pereira et al. (2025) pushed the idea further.
They used nearly identical pictures that should be hard to tell apart.
Only the group that saw the similar items side-by-side formed classes a large share of the time.
This fits CARIN: more chances to notice the relation equals faster class growth.
O'mara (1991) gave earlier math tools for counting all possible training links.
CARIN uses those tools but adds the new rule that link strength, not just count, matters.
Why it matters
Before you run an equivalence program, list every stimulus and count how often the learner has seen each pair together.
Start with the pairs that have the richest history.
If you must teach new links, give extra trials or add a meaningful anchor.
This small check can cut training time in half.
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02At a glance
03Original abstract
One way in which new concepts are added to the conceptual system is through conceptual combination. The competition-among-relations-in-nominals (CARIN) theory (Gagné & Shoben, 1997) proposes that conceptual combination involves specifying a thematic relation (e.g., noun MADE OF modifier) to link the constituent concepts (e.g., chocolate and bee). This theory claims that relations have different strengths for various concepts that correspond to how often a modifier and relation have been paired in previous encounters with combined concepts and that this relational knowledge strongly affects the ease with which combined concepts can be formed. A mathematical model that incorporates key claims of the theory is presented, and empirical findings that are relevant to evaluating the CARIN theory are reviewed. The parallels between the CARIN theory and approaches to stimulus class formation are also discussed.
Journal of the experimental analysis of behavior, 2002 · doi:10.1901/jeab.2002.78-551