Inferensys

Glossary

ConceptSHAP

ConceptSHAP is a method that applies Shapley values to quantify the importance of individual concepts for a model's prediction, providing a game-theoretic attribution for concept-based explanations.
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GAME-THEORETIC CONCEPT ATTRIBUTION

What is ConceptSHAP?

ConceptSHAP applies Shapley values from cooperative game theory to quantify the importance of individual, human-understandable concepts for a specific model prediction, providing a theoretically principled attribution for concept-based explanations.

ConceptSHAP is a concept attribution method that computes Shapley values to assign an importance score to each high-level concept for a given prediction. It models concepts as players in a cooperative game, where the payout is the model's prediction score, and the Shapley value for a concept represents its average marginal contribution across all possible subsets of other concepts. This provides a game-theoretic guarantee of fair credit allocation, satisfying axioms of efficiency, symmetry, dummy, and additivity.

Unlike simpler sensitivity-based measures, ConceptSHAP accounts for concept interactions and redundancies. If two concepts are highly correlated, their individual Shapley values will reflect their unique contributions rather than double-counting shared information. The method requires computing the model's output for all 2^N possible concept coalitions, making exact computation exponential, so sampling approximations like KernelSHAP are typically employed to estimate the values efficiently in high-dimensional concept spaces.

GAME-THEORETIC CONCEPT ATTRIBUTION

Key Properties of ConceptSHAP

ConceptSHAP extends the Shapley value framework from individual input features to high-level semantic concepts, providing a mathematically rigorous method for assigning importance scores to human-understandable abstractions in a model's decision process.

01

Shapley Value Foundation

ConceptSHAP applies cooperative game theory to concept attribution by treating each concept as a player in a coalition. The method computes the marginal contribution of a concept by evaluating the model's prediction with and without that concept across all possible subsets of other concepts. This guarantees a fair, axiomatic distribution of credit that satisfies efficiency, symmetry, dummy, and additivity properties.

02

Concept Coalition Sampling

Because exhaustively evaluating all 2^n concept subsets is computationally intractable, ConceptSHAP uses Monte Carlo sampling to approximate Shapley values. The algorithm randomly permutes the order of concepts and measures the incremental prediction change as each concept is added to the coalition. The average marginal contribution across many permutations converges to the true Shapley value.

03

Concept Intervention Mechanism

To evaluate a prediction without a specific concept, ConceptSHAP must intervene on the model's activations. Common approaches include:

  • Zeroing out the concept direction in activation space
  • Projecting activations onto the subspace orthogonal to the concept vector
  • Resampling activations from a background distribution where the concept is absent Each intervention strategy carries different assumptions about the data distribution.
04

Axiomatic Guarantees

ConceptSHAP inherits four key axioms from Shapley values:

  • Efficiency: The sum of all concept contributions equals the prediction difference from the baseline
  • Symmetry: Concepts with identical marginal contributions receive equal attribution
  • Dummy: A concept that never changes the prediction receives zero attribution
  • Additivity: Attributions combine linearly across models These properties make ConceptSHAP uniquely suitable for regulatory compliance and auditability.
05

Comparison to TCAV

While TCAV measures global concept sensitivity using directional derivatives, ConceptSHAP provides instance-level attribution with formal fairness guarantees. TCAV answers 'How sensitive is this class to a concept?' whereas ConceptSHAP answers 'How much did this specific concept contribute to this specific prediction?' The two methods are complementary: TCAV for global model auditing, ConceptSHAP for local explanation.

06

Interaction Effects Between Concepts

A key advantage of ConceptSHAP is its ability to capture concept interactions. By analyzing how the marginal contribution of one concept changes depending on which other concepts are present, practitioners can identify synergistic or redundant concept pairs. Extensions like Shapley-Taylor indices can explicitly decompose attribution into main effects and interaction terms.

CONCEPT-BASED EXPLAINABILITY

Frequently Asked Questions

Explore the mechanics of ConceptSHAP, a method that brings the rigor of game-theoretic attribution to high-level, human-understandable concepts for auditing neural network decisions.

ConceptSHAP is a model-agnostic explanation method that applies Shapley values from cooperative game theory to quantify the importance of high-level, human-defined concepts for a specific model prediction. It works by defining a cooperative game where each concept is a 'player,' and the 'payout' is the model's prediction score for a target class. The method systematically evaluates the model's output when different coalitions of concepts are present or absent from the input. By averaging the marginal contribution of a concept across all possible subsets of other concepts, ConceptSHAP computes a fair, additive importance score. This provides a principled, mathematically grounded attribution that decomposes a prediction into the sum of its conceptual parts, moving beyond low-level feature attribution to semantic explanations.

METHOD COMPARISON

ConceptSHAP vs. Other Concept Attribution Methods

A feature-level comparison of ConceptSHAP against TCAV, CRP, and Concept Influence for attributing model predictions to high-level concepts.

FeatureConceptSHAPTCAVCRPConcept Influence

Theoretical Foundation

Shapley values (game theory)

Directional derivatives

Layer-wise Relevance Propagation

Causal intervention

Attribution Type

Additive importance score per concept

Global sensitivity score per concept

Relevance heatmaps through layers

Causal effect estimate

Handles Concept Interactions

Local Explanation (per prediction)

Global Explanation (per class)

Requires Concept Vectors

Satisfies Efficiency Axiom

Computational Cost

High (requires sampling coalitions)

Low (single gradient pass)

Medium (backward pass per layer)

Medium (requires intervention per concept)

Prasad Kumkar

About the author

Prasad Kumkar

CEO & MD, Inference Systems

Prasad Kumkar is the CEO & MD of Inference Systems and writes about AI systems architecture, LLM infrastructure, model serving, evaluation, and production deployment. Over 5+ years, he has worked across computer vision models, L5 autonomous vehicle systems, and LLM research, with a focus on taking complex AI ideas into real-world engineering systems.

His work and writing cover AI systems, large language models, AI agents, multimodal systems, autonomous systems, inference optimization, RAG, evaluation, and production AI engineering.