Is Shapley Explanation for a model unique?
- URL: http://arxiv.org/abs/2111.11946v1
- Date: Tue, 23 Nov 2021 15:31:46 GMT
- Title: Is Shapley Explanation for a model unique?
- Authors: Harsh Kumar, Jithu Chandran
- Abstract summary: We explore the relationship between the distribution of a feature and its Shapley value.
Our assessment is that Shapley value for particular feature not only depends on its expected mean but on other moments as well such as variance.
It varies with model outcome (Probability/Log-odds/binary decision such as accept vs reject) and hence model application.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Shapley value has recently become a popular way to explain the predictions of
complex and simple machine learning models. This paper is discusses the factors
that influence Shapley value. In particular, we explore the relationship
between the distribution of a feature and its Shapley value. We extend our
analysis by discussing the difference that arises in Shapley explanation for
different predicted outcomes from the same model. Our assessment is that
Shapley value for particular feature not only depends on its expected mean but
on other moments as well such as variance and there are disagreements for
baseline prediction, disagreements for signs and most important feature for
different outcomes such as probability, log odds, and binary decision generated
using same linear probability model (logit/probit). These disagreements not
only stay for local explainability but also affect the global feature
importance. We conclude that there is no unique Shapley explanation for a given
model. It varies with model outcome (Probability/Log-odds/binary decision such
as accept vs reject) and hence model application.
Related papers
- Shapley Marginal Surplus for Strong Models [0.9831489366502301]
We show that while Shapley values might be accurate explainers of model predictions, machine learning models themselves are often poor explainers of the true data-generating process (DGP)
We introduce a novel variable importance algorithm, Shapley Marginal Surplus for Strong Models, that samples the space of possible models to come up with an inferential measure of feature importance.
arXiv Detail & Related papers (2024-08-16T17:06:07Z) - Efficient Shapley Values Estimation by Amortization for Text
Classification [66.7725354593271]
We develop an amortized model that directly predicts each input feature's Shapley Value without additional model evaluations.
Experimental results on two text classification datasets demonstrate that our amortized model estimates Shapley Values accurately with up to 60 times speedup.
arXiv Detail & Related papers (2023-05-31T16:19:13Z) - On the Strong Correlation Between Model Invariance and Generalization [54.812786542023325]
Generalization captures a model's ability to classify unseen data.
Invariance measures consistency of model predictions on transformations of the data.
From a dataset-centric view, we find a certain model's accuracy and invariance linearly correlated on different test sets.
arXiv Detail & Related papers (2022-07-14T17:08:25Z) - SHAP-XRT: The Shapley Value Meets Conditional Independence Testing [21.794110108580746]
We show that Shapley-based explanation methods and conditional independence testing are closely related.
We introduce the SHAPley EXplanation Randomization Test (SHAP-XRT), a testing procedure inspired by the Conditional Randomization Test (CRT) for a specific notion of local (i.e., on a sample) conditional independence.
We show that the Shapley value itself provides an upper bound to the expected $p$-value of a global (i.e., overall) null hypothesis.
arXiv Detail & Related papers (2022-07-14T16:28:54Z) - Explaining predictive models using Shapley values and non-parametric
vine copulas [2.6774008509840996]
We propose two new approaches for modelling the dependence between the features.
The performance of the proposed methods is evaluated on simulated data sets and a real data set.
Experiments demonstrate that the vine copula approaches give more accurate approximations to the true Shapley values than its competitors.
arXiv Detail & Related papers (2021-02-12T09:43:28Z) - Why do classifier accuracies show linear trends under distribution
shift? [58.40438263312526]
accuracies of models on one data distribution are approximately linear functions of the accuracies on another distribution.
We assume the probability that two models agree in their predictions is higher than what we can infer from their accuracy levels alone.
We show that a linear trend must occur when evaluating models on two distributions unless the size of the distribution shift is large.
arXiv Detail & Related papers (2020-12-31T07:24:30Z) - Causal Shapley Values: Exploiting Causal Knowledge to Explain Individual
Predictions of Complex Models [6.423239719448169]
Shapley values are designed to attribute the difference between a model's prediction and an average baseline to the different features used as input to the model.
We show how these 'causal' Shapley values can be derived for general causal graphs without sacrificing any of their desirable properties.
arXiv Detail & Related papers (2020-11-03T11:11:36Z) - The Struggles of Feature-Based Explanations: Shapley Values vs. Minimal
Sufficient Subsets [61.66584140190247]
We show that feature-based explanations pose problems even for explaining trivial models.
We show that two popular classes of explainers, Shapley explainers and minimal sufficient subsets explainers, target fundamentally different types of ground-truth explanations.
arXiv Detail & Related papers (2020-09-23T09:45:23Z) - Predictive and Causal Implications of using Shapley Value for Model
Interpretation [6.744385328015561]
We established the relationship between Shapley value and conditional independence, a key concept in both predictive and causal modeling.
Our results indicate that, eliminating a variable with high Shapley value from a model do not necessarily impair predictive performance.
More importantly, Shapley value of a variable do not reflect their causal relationship with the target of interest.
arXiv Detail & Related papers (2020-08-12T01:08:08Z) - Decision-Making with Auto-Encoding Variational Bayes [71.44735417472043]
We show that a posterior approximation distinct from the variational distribution should be used for making decisions.
Motivated by these theoretical results, we propose learning several approximate proposals for the best model.
In addition to toy examples, we present a full-fledged case study of single-cell RNA sequencing.
arXiv Detail & Related papers (2020-02-17T19:23:36Z) - Towards Efficient Data Valuation Based on the Shapley Value [65.4167993220998]
We study the problem of data valuation by utilizing the Shapley value.
The Shapley value defines a unique payoff scheme that satisfies many desiderata for the notion of data value.
We propose a repertoire of efficient algorithms for approximating the Shapley value.
arXiv Detail & Related papers (2019-02-27T00:22:43Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.