Resource Rationality Constraint Test
Judge a shortcut against the resources available when the decision occurs
- Difficulty
- Moderate
- Time to result
- ~weeks to results
- Steps
- 6
- Confidence
- 92%
The Resource Rationality Constraint Test evaluates a decision rule relative to the cognitive resources available when it is used. A heuristic such as anchoring may generate biased answers in an idealized model yet remain efficient when someone has little working memory, limited time, or severe fatigue. Start with the apparent error, then identify the resources required by the normative alternative. Measure which constraint is actually binding and explain how the observed shortcut saves effort. Next, relax one constraint—for example by giving more time, external memory, or a calculator—and test whether behavior moves toward the normative benchmark. If it does, redesign the environment to supply that resource. If it does not, investigate incentives, learning, or a different mechanism. The output is a fairer diagnosis and a more targeted intervention.
Origin
Camerer recommended cognitive science and its concept of resource rationality to graduates studying markets. Extracted from Masters in Business.
Core principles
- 01A mistake may be adaptive under genuine cognitive constraints
- 02Evaluate decisions using the resources available at the moment
- 03Identify the constraint before prescribing a correction
- 04Test whether relaxing the constraint changes behavior
- 05Distinguish globally poor rules from locally efficient shortcuts
How to run it
- 1
Name the apparent error
Describe the observed heuristic or deviation and the normative benchmark it fails to meet.
Pro tip Specify the cost of the error rather than merely applying a bias label.
- 2
Inventory decision resources
Measure available time, working memory, attention, information, energy, and relevant experience.
Pro tip Collect these measurements at the moment of choice.
Watch out Do not infer the constraint solely from the resulting mistake.
- 3
Model the shortcut
Explain how the observed heuristic reduces computation or information requirements.
Pro tip Compare both accuracy and cognitive cost with the normative strategy.
- 4
Identify the binding constraint
Determine which scarce resource most plausibly makes the shortcut locally efficient.
Pro tip Prioritize constraints that can be manipulated or supported.
Watch out Several correlated constraints may require a factorial test.
- 5
Relax and test
Provide more of one resource and observe whether decisions improve or the heuristic changes.
Pro tip Use consequential tasks rather than only comprehension questions.
Watch out A null result may mean the intervention failed to relax the constraint.
- 6
Redesign the choice environment
Add durable support such as more time, external memory, automation, or simplified information.
Pro tip Preserve the speed advantage of the shortcut where possible.
Watch out An accurate but burdensome process may be abandoned in practice.
In the wild
A pricing team observes that analysts anchor heavily on the first forecast they see. Rather than assuming irrationality, it tests whether limited time and working memory make the anchor an efficient starting point. One group receives more time and a structured comparison table while another uses the original process.
→ The team learns whether external memory and time reduce anchoring enough to justify changing the workflow.
Common mistakes
Treating every bias as irrationality
A heuristic can be imperfect yet still offer the best accuracy-effort trade-off under the actual constraint.
Guessing the constraint
Interventions fail when designers assume time pressure is causal but the true limitation is attention, knowledge, or incentives.
Ignoring implementation cost
A normatively superior process is not resource-rational if people cannot sustain its time and effort demands.
Is it for you?
Best for
Researchers and designers evaluating fast decisions made under cognitive or operational pressure.
Not ideal for
Cases where deception, conflicting incentives, or missing access—not cognitive scarcity—is the dominant cause.
From the transcript
“they may be optimal given some constraint”
“what is that constraint and can we test that experimentally?”
“if you only have so much working memory, or you're under time pressure, or you're tired.”
From the episode
Advancing Behavioral Economics with Colin Camerer
Colin Camerer