REVIEW 3 major objections 6 minor 46 references
Functional Bilevel Optimization for Predictive Fairness
T0 review · 3 major / 6 minor · reviewed 2026-07-11 · grok-4.5
Pith's one-line read Mean demographic parity for continuous sensitive attributes is a functional bilevel problem that can be optimized with an exact, Hessian-free hypergradient.
desk verdict Clean functional-bilevel take on mean demographic parity for continuous A, with a checkable adjoint and solid methods work; the multi-dataset win claim is real but conditioned on a post-filtered 27/60 subset. read the letter →
The pith
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
The reading
What carries the argument
DPVar(ω)=Var_A(E[f_ω(X)|A]) together with the closed-form adjoint a*_ω(a)=−α(h*_ω(a)−μ_ω) for the squared-loss inner problem; this identity turns the outer hypergradient into a single expectation involving only the centered residual and ∂ωf_ω, eliminating Hessian-vector products.
What would settle it
On the same 27 non-degenerate tabular tasks, recompute true (or high-fidelity cross-fit) DPVar after training: if FBO/ITD no longer dominate under tight DPVar budgets once the inner estimator is replaced by a stronger or oracle conditional-mean fit, the claimed advantage collapses.
Extended reading notes
Core claim
Optimizing DPVar—the variance of the conditional-mean prediction given a continuous sensitive attribute—yields a functional bilevel program whose squared-loss case admits a closed-form adjoint and therefore an exact, Hessian-free hypergradient; the resulting FBO algorithm, together with the more general unrolled ITD method, produces the best or near-best fairness–accuracy trade-offs among strong dependence-penalty and adversarial baselines on synthetic and 60-dataset tabular benchmarks.
Load-bearing premise
A parametric neural net fit on a finite data split must faithfully estimate the true conditional mean of the prediction given a continuous high-dimensional sensitive attribute; if that estimate is wrong, the outer update steers an artifact rather than true mean parity.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper proposes DPVar = Var_A(E[f_ω(X)|A]) as a mean demographic-parity criterion for continuous, high-dimensional sensitive attributes, formulates its optimization as a functional bilevel problem (inner conditional-mean regression, outer accuracy–fairness trade-off), and gives two algorithms: FBO, which uses a closed-form adjoint for squared-loss inner objectives to obtain a Hessian-free hypergradient (Prop. 3.1, App. B), and ITD, which differentiates through unrolled inner steps. Empirically, the methods are evaluated on a controlled synthetic interaction stress test and a semi-synthetic suite built from 60 tabular regression datasets with automatically constructed continuous A, against HSIC, adversarial debiasing, linear-dependence (R²), and GDP/GDP* baselines, with a unified cross-fitted DPVar diagnostic. The abstract and §4 claim that FBO and ITD achieve the lowest or near-lowest aggregate fairness–accuracy regret and match or outperform those baselines.
Significance. If the claims hold, the work is a clear methodological contribution: it cleanly connects a first-moment DP relaxation to functional bilevel optimization, supplies an explicit adjoint (App. B) that avoids Hessian-vector products in the squared-loss case, and ships a reusable continuous-A tabular protocol with a common diagnostic. The synthetic design (β_int knob) is a useful stress test of when mean-targeting should beat full-dependence penalties. The closed-form hypergradient and the dual FBO/ITD design are concrete strengths that other continuous-A fairness work can build on. The main significance risk is empirical scope: the headline multi-dataset superiority is currently summarized on a post-filtered subset rather than the full 60-dataset pool the abstract advertises.
major comments (3)
- Abstract and §4.2 / Fig. 5: the central multi-dataset claim (“lowest or near-lowest aggregate fairness-accuracy regret” on a benchmark “built from 60” datasets) is supported by win rates computed only on the 27 datasets with non-degenerate VAL ranges (≥0.1 on both MSE and DPVar). The other 33 are discarded after inspecting validation fronts because methods collapse. That is a post-hoc selection on the quantity being ranked. Please report the same constrained win-rate (or regret) analysis on the full 60-dataset pool, and/or restate the abstract claim as conditional on non-degenerate trade-offs, with a clear analysis of the 33 degenerate regimes (e.g., whether baselines are competitive there). Without this, the aggregate superiority statement is not fully supported.
- Prop. 3.1 vs Algorithms 1–2: Prop. 3.1 and App. B derive an exact functional hypergradient under h∈L²(P_A) with Hessian 2I. In practice FBO plugs a finite-capacity MLP h_φ into that formula and still describes the hypergradient as “exact.” When A is continuous/high-dimensional, h_φ is only an approximate conditional mean (flagged in Scope and limitations), so the implemented FBO step is an approximate functional hypergradient, not the exact parametric bilevel gradient. Please state this gap explicitly in §3 (when the functional formula is exact vs approximate), and ideally add a small ablation on inner fit quality (M, width of h_φ) vs achieved test DPVar so readers can see that the outer update is not steering an estimation artifact.
- §4 evaluation protocol: all methods are ranked solely by the DPVar diagnostic that FBO/ITD optimize, while HSIC, adversarial, R², and GDP optimize different dependence notions. Criterion-aligned comparison is legitimate for a DPVar paper, but the abstract’s “match or outperform … baselines” reading is stronger than “best under the DPVar metric.” Please either (i) also report at least one non-DPVar dependence measure (e.g., empirical HSIC or adversary accuracy) on the same Pareto points, or (ii) narrow the claim language to superiority under the DPVar diagnostic. This is especially important for GDP*, which is trained after a train-only PCA projection of A when dim(A)>2.
minor comments (6)
- Abstract / §4: “fairness-accuracy regret” is not defined; the reported summary is constrained win rate under Tight/Mid/Loose DPVar budgets. Align terminology with the actual metric.
- Fig. 4 caption is incomplete/garbled (“Each panel the final test Pareto front…”); fix wording and ensure axis labels are readable in the preprint.
- Notation: population weight α, training penalty γ, and selection weight ζ appear late (§4); introduce the distinction once in §3 when F(ω) is defined.
- Algorithm 2 FBO fairness gradient uses an IN-sum involving f_ω(x_i) rather than an explicit ∂_ωf factor written as in Prop. 3.1; a one-line note that autodiff implements the same expectation would help.
- Related work (Fig. 2 / App. A): OT fair-regression citations are well placed; a brief sentence on why post-processing Wasserstein methods are not run as baselines (discrete groups / post-hoc nature) would reduce reviewer questions.
- Appendix D: the 25% predictive-pool rule and corr thresholds are free design choices; a short sensitivity check (e.g., 15% vs 25%) in the appendix would strengthen the benchmark claim.
Circularity Check
No derivation circularity: closed-form hypergradient is derived from the bilevel objective; only minor non-load-bearing self-citation of the authors' functional-bilevel framework.
-
self citation load bearing
[§3 Prop. 3.1; App. B; citation [20]]
"The proof, given in Appendix B, applies the functional implicit-differentiation and adjoint-sensitivity framework of Petrulionyte et al. [20]. The novelty here is the consequence: the squared-loss structure of the inner problem reduces the adjoint to a centered residual, and the hypergradient becomes a single expectation involving h⋆_ω − μ_ω and ∂ωfω(X)."
The general functional adjoint identity is imported from the same authors' prior NeurIPS paper rather than re-proved from scratch. This is minor and not load-bearing for circularity: App. B still carries out the full DPVar-specific calculation (Hessian = 2I, adjoint = −α(h⋆−μ), total gradient), so the closed form is not assumed equal to the target by definition and does not force the empirical claims.
full rationale
The paper defines DPVar as Var_A(E[f_ω(X)|A]), casts its optimization as a functional bilevel problem (inner conditional-mean regression, outer accuracy–DPVar trade-off), and derives a closed-form adjoint for squared loss (Prop. 3.1, App. B). That derivation is algebraic: the inner Hessian collapses to 2I on L2, so the adjoint is the centered residual −α(h⋆_ω−μ_ω) and the hypergradient is an explicit expectation—not a quantity fitted to the target and renamed as a prediction. FBO/ITD then implement that hypergradient; empirical claims are comparisons against HSIC, adversarial, R², and GDP baselines under a shared DPVar diagnostic. Using the same diagnostic for all methods is criterion-aligned evaluation, not mathematical circularity. The only self-citation of note is Petrulionyte et al. [20] for the general functional adjoint-sensitivity identity; Appendix B re-derives the DPVar-specific gradient under stated assumptions (PA,in=PA,out, squared inner loss), so the central result is not forced by an unverified self-citation chain. Semi-synthetic A construction and the 27/60 non-degenerate filter are experimental-design choices, not definitional reductions of a claimed first-principles result. Score 1 for minor self-citation only.
Assumptions & free parameters
free parameters (5)
- fairness training weight γ (and population α / selection ζ)
- inner steps M, unrolling length K, stepsizes η_in / η_out
- MLP architecture (2 hidden layers, width 64, tanh) for f_ω and h_φ
- sensitive-attribute construction fraction (25% of predictive pool) and correlation thresholds
- synthetic unfairness knobs δ, β_int and nuisance dimension of A
assumptions (5)
- domain assumption PA,in = PA,out so that the adjoint and hypergradient identities hold across IN/OUT splits
- standard math Regularity conditions ensuring differentiability of ω ↦ h*_ω in the functional implicit-function setting of Petrulionyte et al. [20]
- standard math Inner squared-loss Hessian w.r.t. h is 2I on L2(PA,in), yielding closed-form adjoint a*_ω = −α(h*_ω − μ_ω)
- domain assumption Mean demographic parity (flat conditional mean) is the appropriate fairness target for continuous high-dimensional A, rather than full independence
- ad hoc to paper Semi-synthetic A built from target-correlated features is a valid methodological proxy for continuous sensitive attributes
invented entities (4)
-
DPVar = Var_A(E[f_ω(X)|A]) as operational continuous-A fairness criterion
-
FBO algorithm (closed-form adjoint hypergradient for squared-loss DPVar)
-
ITD algorithm for DPVar (unrolled inner differentiation)
-
60-dataset semi-synthetic continuous-A fairness benchmark with unified DPVar diagnostic
Cite this review
Pith. "Pith review of Functional Bilevel Optimization for Predictive Fairness." pith.science (2026). https://pith.science/paper/5NWH3GUI
@misc{pith2026260705098,
author = {Pith},
title = {Pith review of: Functional Bilevel Optimization for Predictive Fairness},
year = {2026},
howpublished = {\url{https://pith.science/paper/5NWH3GUI}},
note = {Machine review of arXiv:2607.05098}
}
abstract
When sensitive attributes are continuous and high-dimensional $-$ demographic score vectors, posteriors over attributes, age or income profiles $-$ enforcing full statistical independence is often too restrictive, and existing relaxations rely on indirect dependence penalties or adversarial schemes that do not directly target the fairness-accuracy trade-off. We instead consider mean demographic parity through DPVar, the variance of the conditional-mean prediction given the sensitive attribute, and show that optimizing it yields a functional bilevel problem. We propose two algorithms for this problem: FBO, which uses a closed-form adjoint we derive for the squared-loss case to obtain an exact hypergradient, and ITD, which differentiates through unrolled inner steps and extends beyond squared loss. On synthetic data and a new semi-synthetic benchmark built from 60 tabular regression datasets, both methods achieve the lowest or near-lowest aggregate fairness-accuracy regret, and consistently match or outperform strong HSIC, adversarial, linear-dependence, and generalized-DP baselines.
Figures
Figures from the paper (4 more)
Reference graph
Works this paper leans on
-
[1]
Solon Barocas and Andrew D. Selbst. Big data’s disparate impact.California Law Review, 104 (3):671–732, 2016
2016
-
[2]
A survey on bias and fairness in machine learning.ACM Computing Surveys, 54:1–35, 2021
Ninareh Mehrabi, Fred Morstatter, Nripsuta Saxena, Kristina Lerman, and Aram Galstyan. A survey on bias and fairness in machine learning.ACM Computing Surveys, 54:1–35, 2021
2021
-
[3]
Generalized demographic parity for group fairness.International Conference on Learning Representations (ICLR), 2022
Zhimeng Jiang, Xiaotian Han, Chao Fan, Fan Yang, Ali Mostafavi, and Xia Hu. Generalized demographic parity for group fairness.International Conference on Learning Representations (ICLR), 2022
2022
-
[4]
Equality of opportunity in supervised learning
Moritz Hardt, Eric Price, and Nati Srebro. Equality of opportunity in supervised learning. Advances in Neural Information Processing Systems (NIPS), 2016
2016
-
[5]
Kusner, Joshua Loftus, Chris Russell, and Ricardo Silva
Matt J. Kusner, Joshua Loftus, Chris Russell, and Ricardo Silva. Counterfactual fairness. In Advances in Neural Information Processing Systems (NIPS), 2017
2017
-
[6]
MIT Press, 2023
Solon Barocas, Moritz Hardt, and Arvind Narayanan.Fairness and Machine Learning: Limita- tions and Opportunities. MIT Press, 2023
2023
-
[7]
Fair prediction with disparate impact: A study of bias in recidivism prediction instruments.Big Data, 5(2):153–163, 2017
Alexandra Chouldechova. Fair prediction with disparate impact: A study of bias in recidivism prediction instruments.Big Data, 5(2):153–163, 2017
2017
-
[8]
Inherent trade-offs in the fair determination of risk scores
Jon Kleinberg, Sendhil Mullainathan, and Manish Raghavan. Inherent trade-offs in the fair determination of risk scores. InInnovations in Theoretical Computer Science (ITCS 2017), volume 67 ofLeibniz International Proceedings in Informatics (LIPIcs), pages 43:1–43:23, 2017
2017
Show all 46 references
-
[9]
Fairness-aware classifier with prejudice remover regularizer.Machine Learning and Knowledge Discovery in Databases, pages 35–50, 2012
Toshihiro Kamishima, Shotaro Akaho, Hideki Asoh, and Jun Sakuma. Fairness-aware classifier with prejudice remover regularizer.Machine Learning and Knowledge Discovery in Databases, pages 35–50, 2012
2012
-
[10]
Teo, Le Song, Bernhard Schölkopf, and Alex J
Arthur Gretton, Kenji Fukumizu, Choon H. Teo, Le Song, Bernhard Schölkopf, and Alex J. Smola. A kernel statistical test of independence.Advances in Neural Information Processing Systems (NIPS), 2008
2008
-
[11]
Mitigating unwanted biases with adversarial learning.Proceedings of the Conference on AI, Ethics, and Society (AIES), pages 335–340, 2018
Brian Hu Zhang, Blake Lemoine, and Margaret Mitchell. Mitigating unwanted biases with adversarial learning.Proceedings of the Conference on AI, Ethics, and Society (AIES), pages 335–340, 2018
2018
-
[12]
Censoring representations with an adversary.International Conference on Learning Representations (ICLR), 2016
Harrison Edwards and Amos Storkey. Censoring representations with an adversary.International Conference on Learning Representations (ICLR), 2016
2016
-
[13]
Fairness-aware learning for continuous attributes and treatments.Proceedings of Machine Learning Research (PMLR), 97: 4382–4391, 2019
Jeremie Mary, Clément Calauzènes, and Noureddine El Karoui. Fairness-aware learning for continuous attributes and treatments.Proceedings of Machine Learning Research (PMLR), 97: 4382–4391, 2019
2019
-
[14]
Insung Kong, Kunwoong Kim, and Yongdai Kim. Fair representation learning for continuous sensitive attributes using expectation of integral probability metrics.IEEE Transactions on Pattern Analysis & Machine Intelligence, 47:3784–3795, 2025
2025
-
[15]
Fair Bilevel Neural Network (FairBiNN): On Balancing Fairness and Accuracy via Stackelberg Equilibrium.Advances in Neural Information Processing Systems (NeurIPS), 2024
Mehdi Yazdani-Jahromi, Ali Khodabandeh Yalabadi, AmirArsalan Rajabi, Aida Tayebi, Ivan Garibay, and Ozlem Garibay. Fair Bilevel Neural Network (FairBiNN): On Balancing Fairness and Accuracy via Stackelberg Equilibrium.Advances in Neural Information Processing Systems (NeurIPS), 2024
2024
-
[16]
Nonconvex optimization for regression with fairness constraints
Junpei Komiyama, Akiko Takeda, Junya Honda, and Hajime Shimao. Nonconvex optimization for regression with fairness constraints. InProc. International Conference on Machine Learning (ICML), 2018
2018
-
[17]
Mitigating discrimination in insurance with wasserstein barycenters.PKDD/ECML Workshops, 2023
Arthur Charpentier, François Hu, and Philipp Ratz. Mitigating discrimination in insurance with wasserstein barycenters.PKDD/ECML Workshops, 2023
2023
-
[18]
Should bank stress tests be fair?Management Science, 71(1): 262–278, 2024
Paul Glasserman and Mike Li. Should bank stress tests be fair?Management Science, 71(1): 262–278, 2024. doi: 10.1287/mnsc.2022.02060
2024 doi
-
[19]
FairJob: A Real-World Dataset for Fairness in Online Systems.Advances in Neural Information Processing Systems (NeurIPS), 2024
Mariia Vladimirova, Eustache Diemert, and Federico Pavone. FairJob: A Real-World Dataset for Fairness in Online Systems.Advances in Neural Information Processing Systems (NeurIPS), 2024. 10
2024
-
[20]
Functional bilevel optimization for machine learning.Advances in Neural Information Processing Systems (NeurIPS), 2024
Ieva Petrulionyte, Julien Mairal, and Michael Arbel. Functional bilevel optimization for machine learning.Advances in Neural Information Processing Systems (NeurIPS), 2024
2024
-
[21]
Muhammad Bilal Zafar, Isabel Valera, Manuel Gomez Rodriguez, and Krishna P. Gummadi. Fairness constraints: Mechanisms for fair classification.Proceedings of Machine Learning Research (PMLR), 54:962–970, 2017
2017
-
[22]
A reductions approach to fair classification.Proceedings of Machine Learning Research (PMLR), 80:60–69, 2018
Alekh Agarwal, Alina Beygelzimer, Miroslav Dudik, John Langford, and Hanna Wallach. A reductions approach to fair classification.Proceedings of Machine Learning Research (PMLR), 80:60–69, 2018
2018
-
[23]
Cynthia Dwork, Moritz Hardt, Toniann Pitassi, Omer Reingold, and Richard S. Zemel. Fairness through awareness.Proceedings of the Innovations in Theoretical Computer Science Conference (ITCS), 2012
2012
-
[24]
Fair kernel learning
Adrián Pérez-Suay, Valero Laparra, Gonzalo Mateo-García, Jordi Muñoz-Marí, Luis Gómez- Chova, and Gustau Camps-Valls. Fair kernel learning. InMachine Learning and Knowledge Discovery in Databases - European Conference, ECML PKDD 2017, volume 10534 ofLecture Notes in Computer S...
2017
-
[25]
Kernel dependence reg- ularizers and Gaussian processes with applications to algorithmic fairness.Pattern Recognition, 132:108922, 2022
Zhu Li, Adrián Pérez-Suay, Gustau Camps-Valls, and Dino Sejdinovic. Kernel dependence reg- ularizers and Gaussian processes with applications to algorithmic fairness.Pattern Recognition, 132:108922, 2022
2022
-
[26]
Fair regression with Wasserstein barycenters
Evgenii Chzhen, Christophe Denis, Mohamed Hebiri, Luca Oneto, and Massimiliano Pontil. Fair regression with Wasserstein barycenters. InAdvances in Neural Information Processing Systems (NIPS), 2020
2020
-
[27]
Projection to fairness in statistical learning.arXiv preprint 2005.11720, 2020
Thibaut Le Gouic, Jean-Michel Loubes, and Philippe Rigollet. Projection to fairness in statistical learning.arXiv preprint 2005.11720, 2020
2005 arXiv
-
[28]
A minimax framework for quantifying risk-fairness trade-off in regression.The Annals of Statistics, 50(4):2416–2442, 2022
Evgenii Chzhen and Nicolas Schreuder. A minimax framework for quantifying risk-fairness trade-off in regression.The Annals of Statistics, 50(4):2416–2442, 2022
2022
-
[29]
Fair learning with Wasserstein barycenters for non-decomposable performance measures.International Conference on Artifi- cial Intelligence and Statistics (AISTATS), 2023
Solenne Gaucher, Nicolas Schreuder, and Evgenii Chzhen. Fair learning with Wasserstein barycenters for non-decomposable performance measures.International Conference on Artifi- cial Intelligence and Statistics (AISTATS), 2023
2023
-
[30]
Fairness-aware neural Rényi min- imization for continuous features.International Joint Conference on Artificial Intelligence (IJCAI), 2020
Vincent Grari, Sylvain Lamprier, and Marcin Detyniecki. Fairness-aware neural Rényi min- imization for continuous features.International Joint Conference on Artificial Intelligence (IJCAI), 2020
2020
-
[31]
Veronika Shilova, Emmanuel Malherbe, Giovanni Palma, Laurent Risser, and Jean-Michel Loubes. Fairness-aware grouping for continuous sensitive variables: Application for debiasing face analysis with respect to skin tone.Proceedings of the 28th European Conference on Artificial ...
2025
-
[32]
Fairbatch: Batch selection for model fairness.International Conference on Learning Representations (ICLR), 2021
Yuji Roh, Kangwook Lee, Steven Euijong Whang, and Changho Suh. Fairbatch: Batch selection for model fairness.International Conference on Learning Representations (ICLR), 2021
2021
-
[33]
Fair machine learning under limited demographically labeled data.Workshop on Socially Responsible Machine Learning (SRML), 2022
Mustafa Safa Ozdayi, Murat Kantarcioglu, and Rishabh Iyer. Fair machine learning under limited demographically labeled data.Workshop on Socially Responsible Machine Learning (SRML), 2022
2022
-
[34]
Fairness-informed pareto optimization : An efficient bilevel framework.arXiv preprint arXiv:2601.13448, 2026
Sofiane Tanji, Samuel Vaiter, and Yassine Laguel. Fairness-informed pareto optimization : An efficient bilevel framework.arXiv preprint arXiv:2601.13448, 2026
2026
-
[35]
Hyperparameter optimization with approximate gradient.Proceedings of Machine Learning Research (PMLR), 48:737–746, 2016
Fabian Pedregosa. Hyperparameter optimization with approximate gradient.Proceedings of Machine Learning Research (PMLR), 48:737–746, 2016
2016
-
[36]
UCI machine learning repository, 2019
Dheeru Dua and Casey Graff. UCI machine learning repository, 2019
2019
-
[37]
van Rijn, Bernd Bischl, and Luis Torgo
Joaquin Vanschoren, Jan N. van Rijn, Bernd Bischl, and Luis Torgo. Openml: Networked science in machine learning.ACM SIGKDD Explorations Newsletter, 15(2):49–60, 2014
2014
-
[38]
Mutual information neural estimation.Proceedings of Machine Learning Research (PMLR), 80:531–540, 2018
Mohamed Ishmael Belghazi, Aristide Baratin, Sai Rajeshwar, Sherjil Ozair, Yoshua Bengio, Aaron Courville, and R Devon Hjelm. Mutual information neural estimation.Proceedings of Machine Learning Research (PMLR), 80:531–540, 2018
2018
-
[39]
Domain-adversarial training of neural networks.Journal of Machine Learning Research (JMLR), 17(59):1–35, 2016
Yaroslav Ganin, Evgeniya Ustinova, Hana Ajakan, Pascal Germain, Hugo Larochelle, François Laviolette, Mario Marchand, and Victor Lempitsky. Domain-adversarial training of neural networks.Journal of Machine Learning Research (JMLR), 17(59):1–35, 2016. 11 A Additional Related Wo...
2016
-
[40]
We work in L2(PAout) the space of square integrable functions wrt
Functional gradient in h.We note h(A), φ(A), and EA∼PAout as h, φ, and E for readability. We work in L2(PAout) the space of square integrable functions wrt. the measure PAout equipped with the inner product ⟨u, v⟩L2(PAout ) :=E A∼PAout [u(A)v(A)]. For any direction φ∈L 2(PAout...
-
[41]
The adjointa ⋆ ω ∈L 2(PAin )solves ∂2 hhLin(ω, h⋆ ω)a⋆ ω =−∂ hLout(ω, h⋆ ω), hence 2a⋆ ω(a) =−2α(h ⋆ ω(a)−µ ω) a⋆ ω(a) =−α(h ⋆ ω(a)−µ ω), µ ω :=E A∼PAout [h⋆ ω(A)]
Adjoint.The inner objective is Lin(ω, h) =E (X,A)∼Pin (fω(X)−h(A)) 2 , whose Hessian w.r.t.his∂ 2 hhLin = 2IonL 2(PAin ). The adjointa ⋆ ω ∈L 2(PAin )solves ∂2 hhLin(ω, h⋆ ω)a⋆ ω =−∂ hLout(ω, h⋆ ω), hence 2a⋆ ω(a) =−2α(h ⋆ ω(a)−µ ω) a⋆ ω(a) =−α(h ⋆ ω(a)−µ ω), µ ω :=E A∼PAout [h⋆ ω(A)]
-
[42]
Compute each term •Direct outer term: ∂ωLout(ω, h⋆ ω) = 2E out [(fω(X)−Y)∂ ωfω(X)]
Total gradientBy the functional adjoint identity, ∇ωF(ω) =∂ ωLout(ω, h⋆ ω) +∂ 2 ωhLin(ω, h⋆ ω)[a⋆ ω]. Compute each term •Direct outer term: ∂ωLout(ω, h⋆ ω) = 2E out [(fω(X)−Y)∂ ωfω(X)]. •Implicit (adjoint) term: ∂hLin(ω, h)[φ] =−2E in [(fω(X)−h(A))φ(A)], differentiating w.r.t....
-
[43]
We compute cj =|corr(X j, y)| for every coordinate and rank coordinates in decreasing order ofc j
Rank coordinates by target informativeness.Let Xj denote the jth standardized feature coordinate and letybe the standardized training target. We compute cj =|corr(X j, y)| for every coordinate and rank coordinates in decreasing order ofc j
-
[44]
If this threshold leaves the pool empty, we fall back to the top-ranked coordinates without thresholding
Form a predictive candidate pool.We retain the top 200 ranked coordinates, after discard- ing coordinates with cj <0.02 . If this threshold leaves the pool empty, we fall back to the top-ranked coordinates without thresholding
-
[45]
Concretely, we sample up to 128 other coordinates and define pj = max c̸=j |corr(Xc, Xj)|2, where the maximum is taken over the sampled coordinates
Prefer coordinates that are also proxy-like.For each candidate coordinate Xj, we compute a simple proxy score that measures how predictable it is from the remaining features. Concretely, we sample up to 128 other coordinates and define pj = max c̸=j |corr(Xc, Xj)|2, where the ...
-
[46]
These selected coordinates are removed fromXbefore training the predictor
Define the sensitive attribute and remove it from the predictor input.The sensitive attributeAis formed by taking the top 25% of this candidate pool according tos j, clipped so that at least one predictive coordinate remains in the predictor input. These selected coordinates a...
Reviewed July 11, 2026 · model on record in the stance chip above.
Discussion (0). Sign in to comment.