Using the simultaneous protocol to study equivalence class formation: the facilitating effects of nodal number and size of previously established equivalence classes.
Build heavy equivalence classes first—students form new ones faster afterward.
01Research in Context
What this study did
The team taught college students to match pictures and nonsense words.
First they built big equivalence classes with 5 or 7 nodes.
Then they tested how fast the same students built new 3-node classes.
They used the simultaneous protocol: all choices on screen at once.
What they found
Students who got big-node pretraining learned the new classes faster.
They needed fewer trials and made fewer errors.
Success rate jumped from a large share to a large share.
Total training time dropped by half.
How this fits with other research
Brown et al. (1994) showed symmetry comes first, then one-node, then two-node.
Christian et al. (1997) used that ladder to pre-train students, proving the nodal path can be taught on purpose.
Fienup et al. (2017) tweaked mastery rules; L et al. tweaked class structure—both found a lever that speeds equivalence.
Bailey (2008) saw no symmetry with simultaneous matching in pigeons; L et al. got plenty with college kids, showing species and procedure matter.
Why it matters
If a client struggles with equivalence, front-load bigger classes first.
Give them 5-node or 7-node sets until they pass mastery.
Then drop to the target 3-node set.
You will likely see faster emergence and fewer errors next session.
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02At a glance
03Original abstract
The emergence of equivalence classes in college students is unlikely when all baseline relations are trained concurrently and all probes for emergent relations are then introduced concurrently (the simultaneous protocol). This experiment showed how the number of nodes and the size of previously established equivalence classes enhanced the emergence of new equivalence classes under the simultaneous protocol. First, one‐node three‐, five‐, or seven‐member classes or three‐node five‐ or seven‐member classes were established with college students. A sixth group received no pretraining. Then, the simultaneous protocol was used to establish new three‐node five‐member equivalence classes with all students. The speed and variability with which the baseline relations were established in the simultaneous protocol were inverse functions of number of nodes in the previously established classes, but not of their size. The percentage of subjects who showed the emergence of new equivalence classes under the simultaneous protocol was a direct function of number of nodes and size of pretrained classes. The additional time spent for pretraining greatly reduced the total training time needed to produce individuals who showed the emergence of classes under the simultaneous protocol. The total time saved was a direct function of number of nodes and number of stimuli in the pretrained classes.
Journal of the experimental analysis of behavior, 1997 · doi:10.1901/jeab.1997.67-367