Related Experiment Video
Updated: Feb 21, 2026

A Psychophysics Paradigm for the Collection and Analysis of Similarity Judgments
Published on: March 1, 2022
Contextuality in canonical systems of random variables
Ehtibar N Dzhafarov1, Víctor H Cervantes2, Janne V Kujala3
1Psychological Sciences, Purdue University, West Lafayette, IN, USA ehtibar@purdue.edu.
This study introduces a canonical representation for systems of random variables, defining contextuality based on the compatibility of maximal couplings. It proposes a criterion to identify contextuality in measurement systems.
Area of Science:
- Foundational physics
- Quantum information theory
- Probability theory
Background:
- Measurements are represented by random variables, uniquely identified by content and context.
- Joint distributions arise when random variables share a context.
- Canonical representation simplifies systems by using binary random variables and maximal couplings.
Purpose of the Study:
- To propose a canonical representation for systems of measurements.
- To define contextuality based on the compatibility of maximal couplings within this canonical form.
- To establish a criterion for contextuality in specific measurement systems.
Main Methods:
- Representing measurement systems in a canonical form.
- Defining contextuality based on the incompatibility of maximal couplings with observed joint distributions.
- Analyzing dichotomizations of content-sharing categorical random variables.
Main Results:
- A system is defined as contextual if its canonical representation is contextual.
- Maximal couplings are introduced for content-sharing random variables.
- A criterion for contextuality is established for a specific canonical system.
Conclusions:
- The proposed canonical representation provides a framework for understanding contextuality in measurement systems.
- The criterion for contextuality offers a method for identifying context-dependent behaviors.
- This work contributes to foundational questions in quantum mechanics and information theory.
Related Concept Videos
Random Variables
Uppercase letters such as X or Y denote a random variable. Lowercase letters like x or y denote the value of a random variable. If X is a random variable, then X is written in words, and x is given as a number.
For example, let X = the...
Propagation of Uncertainty from Random Error
Propagation of Uncertainty from Systematic Error
Classification of Systems-I
Homogeneity dictates that if an input x(t) is multiplied by a constant c, the output y(t) is multiplied by the same constant. Mathematically, this is expressed as:
Classification of Systems-II
Entropy Change in Reversible Processes
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.

