ABA Fundamentals

The relation between the generalized matching law and signal-detection theory.

Davison et al. (1978) · Journal of the experimental analysis of behavior 1978
★ The Verdict

The matching law and signal-detection bias are two names for the same equation, giving you a single tool to analyze and adjust client preference.

✓ Read this if BCBAs who like quantitative models and want a fresh lens on reinforcer bias.
✗ Skip if Clinicians looking for ready-to-use protocols or new intervention data.

01Research in Context

01

What this study did

Harris et al. (1978) wrote a math paper, not an experiment. They took the generalized matching law and reworked it into signal-detection language.

The goal was to show that choice bias in matching equations is the same thing as response bias in signal-detection theory.

02

What they found

The authors proved you can swap symbols. The bias term in the matching law equals the bias term in signal-detection theory.

No new data were collected; the paper is pure theory.

03

How this fits with other research

Prelec (1984) is a direct successor. It keeps the same framework but adds a cleaner math proof and an explicit bias coefficient.

Michael (1988) extends the idea into the real world. It tells practitioners to use reinforcer ratios to shift client time toward adaptive tasks.

Neuringer et al. (2007) gives the theory a social twist. Their data show that response patterns matching reinforcer rates look voluntary to observers.

04

Why it matters

You now have one formula that covers both choice and detection. When a client shows bias toward one task, you can treat it like a signal-detection problem: adjust reinforcer rate to move the bias, then check if the shift looks natural to caregivers.

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Plot the client’s response ratio and reinforcer ratio; if they don’t match, tweak the richer schedule until the numbers line up.

02At a glance

Intervention
not applicable
Design
theoretical
Finding
not reported

03Original abstract

The generalized matching law can be applied to a signal-detection matrix to give two equations. The first relates responding in the presence of the stimulus to the reinforcements for the responses, and the second relates responding in the absence of the stimulus to the reinforcements for the responses. Evidence for stimulus discrimination is given by biases that are opposite in sign in the two equations. As the logarithmic ratio and z proportion transformations are similar, the combination of the absolute values of the two logarithmic biases gives a measure equivalent to the signal-detection measures d' and eta. The two equations can also be combined to eliminate the biases caused by the signalling stimuli and to produce a generalized matching-law statement relating overall performance to the obtained reinforcements.

Journal of the experimental analysis of behavior, 1978 · doi:10.1901/jeab.1978.29-331