Negar Rostamzadeh

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UNLEARNING GEO-CULTURAL STEREOTYPES IN MULTILINGUAL LLMS

Alireza Dehghanpour Farashah

Aditi Khandelwal

As multilingual generative models become more widely used, most safety and fairness evaluation techniques still focus on English-language re… (voir plus)sources, while overlooking important cross-cultural factors. This limitation raises concerns about fairness and safety, particularly regarding geoculturally situated stereotypes that hinder the models’ global inclusivity. In this work, we present preliminary findings on the impact of stereotype unlearning across languages, specifically in English, French, and Hindi. Using an adapted version of the SeeGULL dataset, we analyze how unlearning stereotypes in one language influences other languages within multilingual large language models. Our study evaluates two model families, Llama-3.1-8B and Aya-Expanse-8B, to assess whether unlearning in one linguistic context transfers across languages, potentially mitigating or exacerbating biases in multilingual settings.

2025-03-05

ICLR.cc/2025/Workshop/BuildingTrust (accepté)

What Secrets Do Your Manifolds Hold? Understanding the Local Geometry of Generative Models

Ahmed Imtiaz Humayun

Ibtihel Amara

Cristina Nader Vasconcelos

Deepak Ramachandran

Candice Schumann

Junfeng He

Katherine A Heller

Mohammad Havaei

Deep Generative Models are frequently used to learn continuous representations of complex data distributions using a finite number of sample… (voir plus)s. For any generative model, including pre-trained foundation models with GAN, Transformer or Diffusion architectures, generation performance can vary significantly based on which part of the learned data manifold is sampled. In this paper we study the post-training local geometry of the learned manifold and its relationship to generation outcomes for models ranging from toy settings to the latent decoder of the near state-of-the-art Stable Diffusion 1.4 Text-to-Image model. Building on the theory of continuous piecewise-linear (CPWL) generators, we characterize the local geometry in terms of three geometric descriptors - scaling (

2025-01-22

ICLR.cc/2025/Conference (poster)

What Secrets Do Your Manifolds Hold? Understanding the Local Geometry of Generative Models

Ahmed Imtiaz Humayun

Ibtihel Amara

Cristina Nader Vasconcelos

Deepak Ramachandran

Candice Schumann

Junfeng He

Katherine A Heller

Mohammad Havaei

2025-01-22

ICLR.cc/2025/Conference (poster)

The Case for Globalizing Fairness: A Mixed Methods Study on Colonialism, AI, and Health in Africa

Mercy Nyamewaa Asiedu

Awa Dieng

Iskandar Haykel

Stephen R. Pfohl

Chirag Nagpal

Maria Nagawa

Abigail Oppong

Sanmi Koyejo

Katherine Heller

With growing application of machine learning (ML) technologies in healthcare, there have been calls for developing techniques to understand … (voir plus)and mitigate biases these systems may exhibit. Fair-ness considerations in the development of ML-based solutions for health have particular implications for Africa, which already faces inequitable power imbalances between the Global North and South.This paper seeks to explore fairness for global health, with Africa as a case study. We conduct a scoping review to propose axes of disparities for fairness consideration in the African context and delineate where they may come into play in different ML-enabled medical modalities. We then conduct qualitative research studies with 672 general population study participants and 28 experts inML, health, and policy focused on Africa to obtain corroborative evidence on the proposed axes of disparities. Our analysis focuses on colonialism as the attribute of interest and examines the interplay between artificial intelligence (AI), health, and colonialism. Among the pre-identified attributes, we found that colonial history, country of origin, and national income level were specific axes of disparities that participants believed would cause an AI system to be biased.However, there was also divergence of opinion between experts and general population participants. Whereas experts generally expressed a shared view about the relevance of colonial history for the development and implementation of AI technologies in Africa, the majority of the general population participants surveyed did not think there was a direct link between AI and colonialism. Based on these findings, we provide practical recommendations for developing fairness-aware ML solutions for health in Africa.

2024-10-29

Proceedings of the 4th ACM Conference on Equity and Access in Algorithms, Mechanisms, and Optimization (publié)

A Toolbox for Surfacing Health Equity Harms and Biases in Large Language Models

Stephen R. Pfohl

Heather Cole-Lewis

Rory Sayres

Darlene Neal

Mercy Nyamewaa Asiedu

Awa Dieng

Nenad Tomasev

Qazi Mamunur Rashid

Shekoofeh Azizi

Liam G. McCoy

Leo Anthony Celi

Yun Liu

Mike Schaekermann

Alanna Walton

Alicia Parrish

Chirag Nagpal

Preeti Singh

Akeiylah Dewitt

Philip Mansfield … (voir 10 de plus)

Sushant Prakash

Katherine Heller

Alan Karthikesalingam

Christopher Semturs

Joelle Barral

Greg Corrado

Yossi Matias

Jamila Smith-Loud

Ivor Horn

Karan Singhal

2024-09-23

Nature Medicine (publié)

Nteasee: A mixed methods study of expert and general population perspectives on deploying AI for health in African countries

Mercy Nyamewaa Asiedu

Iskandar Haykel

Awa Dieng

K. Kauer

Tousif Ahmed

Florence Ofori

Charisma Chan

Stephen R. Pfohl

Katherine Heller

2024-09-04

ArXiv (prépublication)

Understanding the Local Geometry of Generative Model Manifolds

Ahmed Imtiaz Humayun

Ibtihel Amara

Candice Schumann

Mohammad Havaei

Deep generative models learn continuous representations of complex data manifolds using a finite number of samples during training. For a pr… (voir plus)e-trained generative model, the common way to evaluate the quality of the manifold representation learned, is by computing global metrics like Fr\'echet Inception Distance using a large number of generated and real samples. However, generative model performance is not uniform across the learned manifold, e.g., for \textit{foundation models} like Stable Diffusion generation performance can vary significantly based on the conditioning or initial noise vector being denoised. In this paper we study the relationship between the \textit{local geometry of the learned manifold} and downstream generation. Based on the theory of continuous piecewise-linear (CPWL) generators, we use three geometric descriptors - scaling (

2024-08-15

ArXiv (prépublication)

Position: Cracking the Code of Cascading Disparity Towards Marginalized Communities

Mohammad Havaei

2024-07-08

Proceedings of the 41st International Conference on Machine Learning (publié)

Bias-inducing geometries: exactly solvable data model with fairness implications

Stefano Sarao Mannelli

Federica Gerace

Luca Saglietti

Machine learning (ML) may be oblivious to human bias but it is not immune to its perpetuation. Marginalisation and iniquitous group represen… (voir plus)tation are often traceable in the very data used for training, and may be reflected or even enhanced by the learning models. In this abstract, we aim to clarify the role played by data geometry in the emergence of ML bias. We introduce an exactly solvable high-dimensional model of data imbalance, where parametric control over the many bias-inducing factors allows for an extensive exploration of the bias inheritance mechanism. Through the tools of statistical physics, we analytically characterise the typical properties of learning models trained in this synthetic framework and obtain exact predictions for the observables that are commonly employed for fairness assessment. Simplifying the nature of the problem to its minimal components, we can retrace and unpack typical unfairness behaviour observed on real-world datasets

2024-06-17

ICML.cc/2024/Workshop/GRaM (publié)

Bias-inducing geometries: exactly solvable data model with fairness implications

Stefano Sarao Mannelli

Federica Gerace

Luca Saglietti

2024-06-17

ICML.cc/2024/Workshop/GRaM (publié)

On The Local Geometry of Deep Generative Manifolds

Ahmed Imtiaz Humayun

Ibtihel Amara

Candice Schumann

Mohammad Havaei

In this paper, we study theoretically inspired local geometric descriptors of the data manifolds approximated by pre-trained generative mode… (voir plus)ls. The descriptors – local scaling (ψ), local rank (ν), and local complexity (δ) — characterize the uncertainty, dimensionality, and smoothness on the learned manifold, using only the network weights and architecture. We investigate and emphasize their critical role in understanding generative models. Our analysis reveals that the local geometry is intricately linked to the quality and diversity of generated outputs. Additionally, we see that the geometric properties are distinct for out-of-distribution (OOD) inputs as well as for prompts memorized by Stable Diffusion, showing the possible application of our proposed descriptors for downstream detection and assessment of pre-trained generative models.

2024-06-17

ICML.cc/2024/Workshop/GRaM (publié)

A toolbox for surfacing health equity harms and biases in large language models

Stephen R. Pfohl

Heather Cole-Lewis

Rory A Sayres

Darlene Neal

Mercy Nyamewaa Asiedu

Awa Dieng

Nenad Tomasev

Qazi Mamunur Rashid

Shekoofeh Azizi

Liam G. McCoy

L. A. Celi

Yun Liu

Mike Schaekermann

Alanna Walton

Alicia Parrish

Chirag Nagpal

Preeti Singh

Akeiylah Dewitt

P. A. Mansfield … (voir 10 de plus)

Sushant Prakash

Katherine Heller

Alan Karthikesalingam

Christopher Semturs

Joelle Barral

Greg C. Corrado

Yossi Matias

Jamila Smith-Loud

Ivor Horn

Karan Singhal

2024-03-18

ArXiv (prépublication)