VLDB 2026 Research / reviewers in the wild / expert
Hadi Hosseini
dblp:10/8187
· DBLP profile ↗
51ranked-venue papers
38as first author
35since 2021 · last 2026
0000-0001-5468-6798ORCID · corroborated
Domains — the database's venue-derived domains; a paper can count in several
Artificial intelligence and machine learning · 39 · 34 first-author · 28 since 2021Graphics, computer vision, multimedia, augmented reality and games · 29 · 25 first-author · 20 since 2021Human-computer interaction and ubiquitous computing · 7 · 1 first-author · 5 since 2021Applied, interdisciplinary, general and emerging computing · 6 · 2 first-author · 3 since 2021Systems, architecture and hardware · 1 · 1 first-author · 1 since 2021Security and privacy · 1Databases, data management, data science and information retrieval · 1 · 1 first-author · 1 since 2021Theory of computation · 1
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | Non-Monotonicity in Fair Division of GraphsabstractWe consider the problem of fairly allocating the vertices of a graph among n agents, where the value of a bundle is determined by its cut value---the number of edges with exactly one endpoint in the bundle. This model naturally captures applications such as team formation and network partitioning, where valuations are inherently non-monotonic: the marginal values may be positive, negative, or zero depending on the composition of the bundle. We focus on the fairness notion of envy-freeness up to one item (EF1) and explore its compatibility with several efficiency concepts such as Transfer Stability (TS) that prohibits any transfer of item that benefit one agent at another's expense. For general graphs, our results uncover a non-monotonic relationship between the number of agents n and the existence of allocations satisfying EF1 and transfer stability (TS): such allocations always exist for n=2, may fail to exist for n=3, but exist again for all n>= 4. We further show that existence can be guaranteed for any n by slightly weakening the efficiency requirement or by restricting the graph to forests. All of our positive results are achieved via efficient algorithms. Hadi Hosseini, Shraddha Pathak |
AAAI | 1 |
| 2026 | Fair Societies: Algorithms for House AllocationsabstractHouse allocations concern with matchings involving one-sided preferences, where houses serve as a proxy encoding valuable indivisible resources (e.g. organs, course seats, subsidized public housing units) to be allocated among the agents. Every agent must receive exactly one resource. We study algorithmic approaches towards ensuring fairness in such settings. Minimizing the number of envious agents is known to be computationally hard. We present two tractable approaches to deal with the hardness. When the agents are presented with an initial allocation of houses, we aim to refine this allocation by reallocating a bounded number of houses to reduce the number of envious agents. We show an efficient algorithm when the agents express preference for a bounded number of houses and houses are accepted by a bounded number of agents. Next, we consider single peaked preference domain and present a polynomial time algorithm for finding an allocation that minimize the number of envious agents. We further extend it to satisfy Pareto efficiency. Our former algorithm works for other measures of envy such as total envy, or maximum envy, with suitable modifications. Finally, we present an empirical analysis recording the fairness-welfare trade-off of our algorithms. Hadi Hosseini, Sanjukta Roy 0001, Aditi Sethia |
AAAI | 1 |
| 2025 | Strategyproof Matching of Roommates and RoomsabstractWe initiate the study of matching roommates and rooms wherein the preferences of agents over other agents and rooms are complementary and represented by Leontief utilities. In this setting, 2n agents must be paired up and assigned to n rooms. Each agent has cardinal valuations over the rooms as well as compatibility values over all other agents. Under Leontief preferences, an agent’s utility for a matching is the minimum of the two values. We focus on the tradeoff between maximizing utilitarian social welfare and strategyproofness. Our main result shows that—in a stark contrast to the additive case— under binary Leontief utilities, there exist strategyproof mechanisms that maximize the social welfare. We further devise a strategyproof mechanism that implements such a welfare maximizing algorithm and is parameterized by the number of agents. Along the way, we highlight several possibility and impossibility results, and give upper bounds and lower bounds for welfare with or without strategyproofness. Hadi Hosseini, Shivika Narang, Sanjukta Roy 0001 |
AAAI | 1 |
| 2025 | AI Education in a Mirror: Challenges Faced by Academic and Industry Experts
Mahir Akgun, Hadi Hosseini |
AIED (2) | 2 |
| 2025 | MatchXplain: Analyzing Preferences, Explaining Outcomes, and Simplifying DecisionsabstractMatching markets, where agents are assigned to one another based on preferences and constraints, are fundamental in various AI-driven applications such as school choice, content matching, and recommender systems. A key challenge in these markets is understanding preference data, as the interpretability of algorithmic solutions hinges on accurately capturing and explaining preferences. We introduce MatchXplain, a platform that integrates preference explanation with a robust matching engine. MatchXplain offers a layered approach for explaining preferences, computing diverse matching solutions, and providing interactive visualizations to enhance user understanding. By bridging algorithmic decision-making with explainability, MatchXplain improves transparency and trust in algorithmic matching markets. Hadi Hosseini, Yubo Jing, Ronak Singh |
IJCAI | 1 |
| 2025 | Distributive Fairness in Large Language Models: Evaluating Alignment with Human ValuesabstractThe growing interest in employing large language models (LLMs) for decision-making in social and economic contexts has raised questions about their potential to function as agents in these domains. A significant number of societal problems involve the distribution of resources, where fairness, along with economic efficiency, play a critical role in the desirability of outcomes. In this paper, we examine whether LLM responses adhere to fundamental fairness concepts such as equitability, envy-freeness, and Rawlsian maximin, and investigate their alignment with human preferences. We evaluate the performance of several LLMs, providing a comparative benchmark of their ability to reflect these measures. Our results demonstrate a lack of alignment between current LLM responses and human distributional preferences. Moreover, LLMs are unable to utilize money as a transferable resource to mitigate inequality. Nonetheless, we demonstrate a stark contrast when (some) LLMs are tasked with selecting from a predefined menu of options rather than generating one. In addition, we analyze the robustness of LLM responses to variations in semantic factors (e.g. intentions or personas) or non-semantic prompting changes (e.g. templates or orderings). Finally, we highlight potential strategies aimed at enhancing the alignment of LLM behavior with well-established fairness concepts. Hadi Hosseini, Samarth Khanna |
NeurIPS | 1 |
| 2025 | Matching Markets Meet LLMs: Algorithmic Reasoning with Ranked PreferencesabstractThe rise of Large Language Models (LLMs) has driven progress in reasoning tasks, from program synthesis to scientific hypothesis generation, yet their ability to handle ranked preferences and structured algorithms in combinatorial domains remains underexplored.
We study matching markets, a core framework behind applications like resource allocation and ride-sharing, which require reconciling individual ranked preferences to ensure stable outcomes. We evaluate seven state‐of‐the‐art models on a hierarchy of preference‐based reasoning tasks---ranging from stable‐matching generation to instability detection, instability resolution, and fine-grained preference queries---to systematically expose their logical and algorithmic limitations in handling ranked inputs. Surprisingly, even top-performing models with advanced reasoning struggle to resolve instability in large markets, often failing to identify blocking pairs or execute algorithms iteratively. We further show that parameter-efficient fine-tuning (LoRA) significantly improves performance in small markets, but fails to bring about a similar improvement on large instances, suggesting the need for more sophisticated strategies to improve LLMs' reasoning with larger-context inputs. Hadi Hosseini, Samarth Khanna, Ronak Singh |
NeurIPS | 1 |
| 2025 | Surprisingly Popular Voting with Concentric Rank-Order ModelsabstractAn important problem on social information sites is the recovery of ground truth from individual reports when the experts are in the minority. The wisdom of the crowd, i.e. the collective opinion of a group of individuals fails in such a scenario. However, the surprisingly popular (SP) algorithm[15] can recover the ground truth even when the experts are in the minority, by asking the individuals to report additional prediction reports--their beliefs about the reports of others. Several recent works have extended the surprisingly popular algorithm to an equivalent voting rule (SP-voting) to recover the ground truth ranking over a set of m alternatives. However, we are yet to fully understand when SP-voting can recover the ground truth ranking, and if so, how many samples (votes and predictions) it needs. We answer this question by proposing two rank-order models and analyzing the sample complexity of SP-voting under these models. In particular, we propose concentric mixtures of Mallows and Plackett-Luce models with G (≥ 2) groups. Our models generalize previously proposed concentric mixtures of Mallows models with 2 groups, and we highlight the importance of G > 2 groups by identifying three distinct groups (expert, intermediate, and non-expert) from existing datasets. Next, we provide conditions on the parameters of the underlying models so that SP-voting can recover ground-truth rankings with high probability, and also derive sample complexities under the same. We complement the theoretical results by evaluating SP-voting on simulated and real datasets. Hadi Hosseini, Debmalya Mandal, Amrit Puhan |
WWW | 1 |
| 2025 | Fair distribution of delivery ordersabstractWe initiate the study of fair distribution of delivery tasks among a set of agents wherein delivery jobs are placed along the vertices of a graph . Our goal is to fairly distribute delivery costs (distance traveled to complete the deliveries) among a fixed set of agents while satisfying some desirable notions of economic efficiency. We adopt well-established fairness concepts—such as envy-freeness up to one item (EF1) and minimax share (MMS)—to our setting and show that fairness is often incompatible with the efficiency notion of social optimality . We then characterize instances that admit fair and socially optimal solutions by exploiting graph structures. We further show that achieving fairness along with Pareto optimality is computationally intractable. We complement this by designing an XP algorithm (parameterized by the number of agents) for finding MMS and Pareto optimal solutions on every tree instance, and show that the same algorithm can be modified to find efficient solutions along with EF1, when such solutions exist. The latter crucially relies on an intriguing result that in our setting EF1 and Pareto optimality jointly imply MMS. We conclude by theoretically and experimentally analyzing the price of fairness. Hadi Hosseini, Shivika Narang, Tomasz Was |
Artif. Intell. | 1 |
| 2024 | The Fairness Fair: Bringing Human Perception into Collective Decision-MakingabstractFairness is one of the most desirable societal principles in collective decision-making. It has been extensively studied in the past decades for its axiomatic properties and has received substantial attention from the multiagent systems community in recent years for its theoretical and computational aspects in algorithmic decision-making. However, these studies are often not sufficiently rich to capture the intricacies of human perception of fairness in the ambivalent nature of the real-world problems. We argue that not only fair solutions should be deemed desirable by social planners (designers), but they should be governed by human and societal cognition, consider perceived outcomes based on human judgement, and be verifiable. We discuss how achieving this goal requires a broad transdisciplinary approach ranging from computing and AI to behavioral economics and human-AI interaction. In doing so, we identify shortcomings and long-term challenges of the current literature of fair division, describe recent efforts in addressing them, and more importantly, highlight a series of open research directions. Hadi Hosseini |
AAAI | 1 |
| 2024 | The Degree of Fairness in Efficient House AllocationabstractThe classic house allocation problem is primarily concerned with finding a matching between a set of agents and a set of houses that guarantees some notion of economic efficiency (e.g. utilitarian welfare). While recent works have shifted focus on achieving fairness (e.g. minimizing the number of envious agents), they often come with notable costs on efficiency notions such as utilitarian or egalitarian welfare. We investigate the trade-offs between these welfare measures and several natural fairness measures that rely on the number of envious agents, the total (aggregate) envy of all agents, and maximum total envy of an agent. In particular, by focusing on envy-free allocations, we first show that, should one exist, finding an envy-free allocation with maximum utilitarian or egalitarian welfare is computationally tractable. We highlight a rather stark contrast between utilitarian and egalitarian welfare by showing that finding utilitarian welfare maximizing allocations that minimize the aforementioned fairness measures can be done in polynomial time while their egalitarian counterparts remain intractable (for the most part) even under binary valuations. We complement our theoretical findings by giving insights into the relationship between the different fairness measures and by conducting empirical analysis. Hadi Hosseini, Medha Kumar, Sanjukta Roy 0001 |
ECAI | 1 |
| 2024 | Distribution of Chores with Information AsymmetryabstractA well-regarded fairness notion when dividing indivisible chores is envy-freeness up to one item (EF1), which requires that pairwise envy can be eliminated by the removal of a single item. While an EF1 and Pareto optimal (PO) allocation of goods can always be found via well-known algorithms, even the existence of such solutions for chores remains open, to date. We take an epistemic approach utilizing information asymmetry by introducing dubious chores–items that inflict no cost on receiving agents but are perceived costly by others. On a technical level, dubious chores provide a more fine-grained approximation of envy-freeness than EF1. We show that finding allocations with minimal number of dubious chores is computationally hard. Nonetheless, we prove the existence of envy-free and fractional PO allocations for n agents with only 2n−2 dubious chores and strengthen it to n−1 dubious chores in four special classes of valuations. Our experimental analysis demonstrates that often only a few dubious chores are needed to achieve envy-freeness. Hadi Hosseini, Joshua Kavner, Tomasz Was, Lirong Xia |
ECAI | 1 |
| 2024 | Algorithmic Fairness in Distribution of Resources and Tasks
Hadi Hosseini |
IJCAI | 1 |
| 2024 | Fair Distribution of Delivery Orders
Hadi Hosseini, Shivika Narang, Tomasz Was |
IJCAI | 1 |
| 2024 | Strategic Aspects of Stable Matching Markets: A Survey
Hadi Hosseini, Shraddha Pathak |
IJCAI | 1 |
| 2024 | Putting Gale & Shapley to Work: Guaranteeing Stability Through LearningabstractTwo-sided matching markets describe a large class of problems wherein participants from one side of the market must be matched to those from the other side according to their preferences. In many real-world applications (e.g. content matching or online labor markets), the knowledge about preferences may not be readily available and must be learned, i.e., one side of the market (aka agents) may not know their preferences over the other side (aka arms). Recent research on online settings has focused primarily on welfare optimization aspects (i.e. minimizing the overall regret) while paying little attention to the game-theoretic properties such as the stability of the final matching. In this paper, we exploit the structure of stable solutions to devise algorithms that improve the likelihood of finding stable solutions. We initiate the study of the sample complexity of finding a stable matching, and provide theoretical bounds on the number of samples needed to reach a stable matching with high probability. Finally, our empirical results demonstrate intriguing tradeoffs between stability and optimality of the proposed algorithms, further complementing our theoretical findings. Hadi Hosseini, Sanjukta Roy 0001, Duohan Zhang |
NeurIPS | 1 |
| 2024 | The Surprising Effectiveness of SP Voting with Partial PreferencesabstractWe consider the problem of recovering the ground truth ordering (ranking, top-$k$, or others) over a large number of alternatives.
The wisdom of crowd is a heuristic approach based on Condorcet's Jury theorem to address this problem through collective opinions.
This approach fails to recover the ground truth when the majority of the crowd is misinformed. The \emph{surprisingly popular} (SP) algorithm~\citep{prelec2017solution} is an alternative approach that is able to recover the ground truth even when experts are in minority. The SP algorithm requires the voters to predict other voters' report in the form of a full probability distribution over all rankings of alternatives. However, when the number of alternatives, $m$, is large, eliciting the prediction report or even the vote over $m$ alternatives might be too costly.
In this paper, we design a scalable alternative of the SP algorithm which only requires eliciting partial preferences from the voters, and propose new variants of the SP algorithm. In particular, we propose two versions---\emph{Aggregated-SP} and \emph{Partial-SP}---that ask voters to report vote and prediction on a subset of size $k$ ($\ll m$) in terms of top alternative, partial rank, or an approval set. Through a large-scale crowdsourcing experiment on MTurk, we show that both of our approaches outperform conventional preference aggregation algorithms for the recovery of ground truth rankings, when measured in terms of Kendall-Tau distance and Spearman's $\rho$. We further analyze the collected data and demonstrate that voters' behavior in the experiment, including the minority of the experts, and the SP phenomenon, can be correctly simulated by a concentric mixtures of Mallows model. Finally, we provide theoretical bounds on the sample complexity of SP algorithms with partial rankings to demonstrate the theoretical guarantees of the proposed methods. Hadi Hosseini, Debmalya Mandal, Amrit Puhan |
NeurIPS | 1 |
| 2024 | Graphical house allocation with identical valuations
Hadi Hosseini, Andrew McGregor 0001, Justin Payan, Rik Sengupta, Rohit Vaish, Vignesh Viswanathan |
Auton. Agents Multi Agent Syst. | 1 |
| 2024 | Class fairness in online matching
Hadi Hosseini, Zhiyi Huang 0002, Ayumi Igarashi 0001, Nisarg Shah 0001 |
Artif. Intell. | 1 |
| 2024 | An experimental study on beamforming architecture and full-duplex wireless across two operational outdoor massive MIMO networks
Hadi Hosseini, Ahmed Almutairi, Syed Muhammad Hashir, Ehsan Aryafar, Joseph David Camp |
Perform. Evaluation | 1 |
| 2023 | Class Fairness in Online MatchingabstractWe initiate the study of fairness among classes of agents in online bipartite matching where there is a given set of offline vertices (aka agents) and another set of vertices (aka items) that arrive online and must be matched irrevocably upon arrival. In this setting, agents are partitioned into a set of classes and the matching is required to be fair with respect to the classes. We adopt popular fairness notions (e.g. envy-freeness, proportionality, and maximin share) and their relaxations to this setting and study deterministic and randomized algorithms for matching indivisible items (leading to integral matchings) and for matching divisible items (leading to fractional matchings). For matching indivisible items, we propose an adaptive-priority-based algorithm, MATCH-AND-SHIFT, prove that it achieves (1/2)-approximation of both class envy-freeness up to one item and class maximin share fairness, and show that each guarantee is tight. For matching divisible items, we design a water-filling-based algorithm, EQUAL-FILLING, that achieves (1-1/e)-approximation of class envy-freeness and class proportionality; we prove (1-1/e) to be tight for class proportionality and establish a 3/4 upper bound on class envy-freeness. Hadi Hosseini, Zhiyi Huang 0002, Ayumi Igarashi 0001, Nisarg Shah 0001 |
AAAI | 1 |
| 2023 | Fairly Allocating Goods and (Terrible) ChoresabstractWe study the fair allocation of mixture of indivisible goods and chores under lexicographic preferences---a subdomain of additive preferences. A prominent fairness notion for allocating indivisible items is envy-freeness up to any item (EFX). Yet, its existence and computation has remained a notable open problem. By identifying a class of instances with "terrible chores", we show that determining the existence of an EFX allocation is NP-complete. This result immediately implies the intractability of EFX under additive preferences. Nonetheless, we propose a natural subclass of lexicographic preferences for which an EFX and Pareto optimal (PO) allocation is guaranteed to exist and can be computed efficiently for any mixed instance. Focusing on two weaker fairness notions, we investigate finding EF1 and Pareto optimal allocations for special instances with terrible chores, and show that MMS and PO allocations can be computed efficiently for any mixed instance with lexicographic preferences. Hadi Hosseini, Aghaheybat Mammadov, Tomasz Was |
IJCAI | 1 |
| 2023 | Ordinal Maximin Share Approximation for Goods (Extended Abstract)abstractIn fair division of indivisible goods, l-out-of-d maximin share (MMS) is the value that an agent can guarantee by partitioning the goods into d bundles and choosing the l least preferred bundles. Most existing works aim to guarantee to all agents a constant fraction of their 1-out-of-n MMS. But this guarantee is sensitive to small perturbation in agents' cardinal valuations. We consider a more robust approximation notion, which depends only on the agents' ordinal rankings of bundles. We prove the existence of l-out-of-floor((l+1/2)n) MMS allocations of goods for any integer l greater than or equal to 1, and present a polynomial-time algorithm that finds a 1-out-of-ceiling(3n/2) MMS allocation when l = 1. We further develop an algorithm that provides a weaker ordinal approximation to MMS for any l > 1. Hadi Hosseini, Andrew Searns, Erel Segal-Halevi |
IJCAI | 1 |
| 2023 | Mind the Gap: The Illusion of Skill Acquisition in Computational ThinkingabstractWith the advent of online educational platforms and the advances in pedagogical technologies, self-directed learning has emerged as one of the most popular modes of learning. Distance education---elevated by the COVID-19 pandemic---involves methods of instruction through a variety of remote activities which often rely on educational videos for mastery. In the absence of direct student engagement, the asynchronous nature of remote activities may deteriorate the quality of education for learners. Students often have an illusion of skill acquisition after watching videos, which results in overestimation of abilities and skills. We focus on the efficacy of skill acquisition through interactive technologies and assess their impact on computational thinking in comparison with delivery through other traditional media (e.g. videos and texts). In particular, we investigate the relationship between actual learning, perception of learning, and learners' confidence in adult learners. Our results reveal intriguing observations about the role of interactivity and visualization and their implications on the pedagogical design for self-directed learning modules. Yeting Bao, Hadi Hosseini |
SIGCSE (1) | 2 |
| 2022 | Two for One & One for All: Two-Sided Manipulation in Matching MarketsabstractStrategic behavior in two-sided matching markets has been traditionally studied in a "one-sided" manipulation setting where the agent who misreports is also the intended beneficiary. Our work investigates "two-sided" manipulation of the deferred acceptance algorithm where the misreporting agent and the manipulator (or beneficiary) are on different sides. Specifically, we generalize the recently proposed accomplice manipulation model (where a man misreports on behalf of a woman) along two complementary dimensions: (a) the two for one model, with a pair of misreporting agents (man and woman) and a single beneficiary (the misreporting woman), and (b) the one for all model, with one misreporting agent (man) and a coalition of beneficiaries (all women). Our main contribution is to develop polynomial-time algorithms for finding an optimal manipulation in both settings. We obtain these results despite the fact that an optimal one for all strategy fails to be inconspicuous, while it is unclear whether an optimal two for one strategy satisfies the inconspicuousness property. We also study the conditions under which stability of the resulting matching is preserved. Experimentally, we show that two-sided manipulations are more frequently available and offer better quality matches than their one-sided counterparts. Hadi Hosseini, Fatima Umar, Rohit Vaish |
IJCAI | 1 |
| 2022 | Ordinal Maximin Share Approximation for GoodsabstractIn fair division of indivisible goods, ℓ-out-of-d maximin share (MMS) is the value that an agent can guarantee by partitioning the goods into d bundles and choosing the ℓ least preferred bundles. Most existing works aim to guarantee to all agents a constant fraction of their 1-out-of-n MMS. But this guarantee is sensitive to small perturbation in agents' cardinal valuations. We consider a more robust approximation notion, which depends only on the agents' ordinal rankings of bundles. We prove the existence of ℓ-out-of-⌊(ℓ + 1/2)n⌋ MMS allocations of goods for any integer ℓ ≥ 1, and present a polynomial-time algorithm that finds a 1-out-of-⌈3n/2⌉ MMS allocation when ℓ=1. We further develop an algorithm that provides a weaker ordinal approximation to MMS for any ℓ > 1. Hadi Hosseini, Andrew Searns, Erel Segal-Halevi |
J. Artif. Intell. Res. | 1 |
| 2021 | Fair Stable Matchings Under Correlated Preferences (Student Abstract)abstractStable matching models are widely used in market design, school admission, and donor organ exchange. The classic Deferred Acceptance (DA) algorithm guarantees a stable matching that is optimal for one side (say men) and pessimal for the other (say women). A sex-equal stable matching aims at providing a fair solution to this problem. We demonstrate that under a class of correlated preferences, the DA algorithm either returns a sex-equal solution or has a very low sex-equality cost. Angelina Brilliantova, Hadi Hosseini |
AAAI | 2 |
| 2021 | Necessarily Optimal One-Sided MatchingsabstractWe study the classical problem of matching n agents to n objects, where the agents have ranked preferences over the objects. We focus on two popular desiderata from the matching literature: Pareto optimality and rank-maximality. Instead of asking the agents to report their complete preferences, our goal is to learn a desirable matching from partial preferences, specifically a matching that is necessarily Pareto optimal (NPO) or necessarily rank-maximal (NRM) under any completion of the partial preferences. We focus on the top-k model in which agents reveal a prefix of their preference rankings. We design efficient algorithms to check if a given matching is NPO or NRM, and to check whether such a matching exists given top-k partial preferences. We also study online algorithms for eliciting partial preferences adaptively, and prove bounds on their competitive ratio. Hadi Hosseini, Vijay Menon 0001, Nisarg Shah 0001, Sujoy Sikdar |
AAAI | 1 |
| 2021 | Fair and Efficient Allocations under Lexicographic PreferencesabstractEnvy-freeness up to any good (EFX) provides a strong and intuitive guarantee of fairness in the allocation of indivisible goods. But whether such allocations always exist or whether they can be efficiently computed remains an important open question. We study the existence and computation of EFX in conjunction with various other economic properties under lexicographic preferences--a well-studied preference restriction model in artificial intelligence and economics. In sharp contrast to the known results for additive valuations, we not only prove the existence of EFX and Pareto optimal allocations, but in fact provide an algorithmic characterization of these two properties. We also characterize the mechanisms that are, in addition, strategyproof, non-bossy, and neutral. When the efficiency notion is strengthened to rank-maximality, we obtain non-existence and computational hardness results, and show that tractability can be restored when EFX is relaxed to another well-studied fairness notion called maximin share guarantee (MMS). Hadi Hosseini, Sujoy Sikdar, Rohit Vaish, Lirong Xia |
AAAI | 1 |
| 2021 | Surprisingly Popular Voting Recovers Rankings, Surprisingly!abstractThe wisdom of the crowd has long become the de facto approach for eliciting information from individuals or experts in order to predict the ground truth. However, classical democratic approaches for aggregating individual \emph{votes} only work when the opinion of the majority of the crowd is relatively accurate. A clever recent approach, \emph{surprisingly popular voting}, elicits additional information from the individuals, namely their \emph{prediction} of other individuals' votes, and provably recovers the ground truth even when experts are in minority. This approach works well when the goal is to pick the correct option from a small list, but when the goal is to recover a true ranking of the alternatives, a direct application of the approach requires eliciting too much information. We explore practical techniques for extending the surprisingly popular algorithm to ranked voting by partial votes and predictions and designing robust aggregation rules. We experimentally demonstrate that even a little prediction information helps surprisingly popular voting outperform classical approaches. Hadi Hosseini, Debmalya Mandal, Nisarg Shah 0001, Kevin Shi |
IJCAI | 1 |
| 2021 | Guaranteeing Maximin Shares: Some Agents Left BehindabstractThe maximin share (MMS) guarantee is a desirable fairness notion for allocating indivisible goods. While MMS allocations do not always exist, several approximation techniques have been developed to ensure that all agents receive a fraction of their maximin share. We focus on an alternative approximation notion, based on the population of agents, that seeks to guarantee MMS for a fraction of agents. We show that no optimal approximation algorithm can satisfy more than a constant number of agents, and discuss the existence and computation of MMS for all but one agent and its relation to approximate MMS guarantees. We then prove the existence of allocations that guarantee MMS for 2/3 of agents, and devise a polynomial time algorithm that achieves this bound for up to nine agents. A key implication of our result is the existence of allocations that guarantee the value that an agent receives by partitioning the goods into 3n/2 bundles, improving the best known guarantee when goods are partitioned into 2n-2 bundles. Finally, we provide empirical experiments using synthetic data. Hadi Hosseini, Andrew Searns |
IJCAI | 1 |
| 2021 | Accomplice Manipulation of the Deferred Acceptance AlgorithmabstractThe deferred acceptance algorithm is an elegant solution to the stable matching problem that guarantees optimality and truthfulness for one side of the market. Despite these desirable guarantees, it is susceptible to strategic misreporting of preferences by the agents on the other side. We study a novel model of strategic behavior under the deferred acceptance algorithm: manipulation through an accomplice. Here, an agent on the proposed-to side (say, a woman) partners with an agent on the proposing side---an accomplice---to manipulate on her behalf (possibly at the expense of worsening his match). We show that the optimal manipulation strategy for an accomplice comprises of promoting exactly one woman in his true list (i.e., an inconspicuous manipulation). This structural result immediately gives a polynomial-time algorithm for computing an optimal accomplice manipulation. We also study the conditions under which the manipulated matching is stable with respect to the true preferences. Our experimental results show that accomplice manipulation outperforms self manipulation both in terms of the frequency of occurrence as well as the quality of matched partners. Hadi Hosseini, Fatima Umar, Rohit Vaish |
IJCAI | 1 |
| 2021 | Customizing Feedback for Introductory Programming Courses Using Semantic Clusters
Victor J. Marin, Hadi Hosseini, Carlos R. Rivero |
ITS | 2 |
| 2021 | Computational Thinking, Perception, and Confidence in Distance LearningabstractOne of the key factors for measuring success in distance learning is student interaction with learning materials. Remote instruction has gained substantial traction with the advent of online education, and this attention has increased in the presence of global pandemics. The asynchronous nature of remote learning has deteriorated the quality of education for learners, which calls for the design of novel interactive techniques to promote student engagement. We study the impact of traditional learning tools such as textbooks and videos in contrast with interactive learning media in computational and algorithmic thinking, and investigate students' perception of learning and actual learning comprehension in higher education. Yeting Bao, Hadi Hosseini |
SIGCSE | 2 |
| 2021 | Learning to Recognize Semantically Similar Program Statements in Introductory Programming AssignmentsabstractWith the continuously increasing population of students enrolling in introductory programming courses, instructors are facing challenges to provide timely and qualitative feedback. Automated systems are appealing to address scalability issues and provide personalized feedback to students. Many of the current approaches fail to handle flexible grading schemes and low-level feedback regarding (a set of) program statements. The combination of program static analysis in the form of program dependence graphs and approximate graph comparisons is promising to address the previous shortcomings. Current techniques require pairwise comparisons of student programs that does not scale in practice. We explore techniques to learn models that are able to recognize whether an unseen program statement belong to a semantically-similar set of program statements. Our initial results on a publicly-available introductory programming assignment indicate that it is possible to assign with high accuracy an individual program statement to some of the popular semantically-similar sets, and a large proportion is covered with these, which suggests feedback provided by instructors can be automatically propagated to other student programs. Mayur Sunil Jawalkar, Hadi Hosseini, Carlos R. Rivero |
SIGCSE | 2 |
| 2020 | MatchU: An Interactive Matching PlatformabstractMatchU is a web-based platform that offers an interactive framework to find how to form mutually-beneficial relationships, decide how to distribute resources, or resolve conflicts through a suite of matching algorithms rooted in economics and artificial intelligence. In this paper, we discuss MatchU's vision, solutions, and future directions. James Ferris, Hadi Hosseini |
AAAI | 2 |
| 2020 | Fair Division Through Information WithholdingabstractEnvy-freeness up to one good (EF1) is a well-studied fairness notion for indivisible goods that addresses pairwise envy by the removal of at most one good. In the worst case, each pair of agents might require the (hypothetical) removal of a different good, resulting in a weak aggregate guarantee. We study allocations that are nearly envy-free in aggregate, and define a novel fairness notion based on information withholding. Under this notion, an agent can withhold (or hide) some of the goods in its bundle and reveal the remaining goods to the other agents. We observe that in practice, envy-freeness can be achieved by withholding only a small number of goods overall. We show that finding allocations that withhold an optimal number of goods is computationally hard even for highly restricted classes of valuations. In contrast to the worst-case results, our experiments on synthetic and real-world preference data show that existing algorithms for finding EF1 allocations withhold a close-to-optimal amount of information. Hadi Hosseini, Sujoy Sikdar, Rohit Vaish, Hejun Wang, Lirong Xia |
AAAI | 1 |
| 2020 | Fairness Does Not Imply Satisfaction (Student Abstract)abstractFair division is a subfield of multiagent systems that is concerned with object distribution. When objects are indivisible, the Maximin Share Guarantee (MMS) is a desirable fairness notion; however, it is not guaranteed to exist. While MMS allocations may not always exist, a relaxation of MMS is guaranteed to exist. We show that there exists a family of instances for which this relaxation fails to guarantee the MMS value for all but a small constant number of agents. Andrew Searns, Hadi Hosseini |
AAAI | 2 |
| 2020 | Fair Division of Time: Multi-layered Cake CuttingabstractWe initiate the study of multi-layered cake cutting with the goal of fairly allocating multiple divisible resources (layers of a cake) among a set of agents. The key requirement is that each agent can only utilize a single resource at each time interval. Several real-life applications exhibit such restrictions on overlapping pieces, for example, assigning time intervals over multiple facilities and resources or assigning shifts to medical professionals. We investigate the existence and computation of envy-free and proportional allocations. We show that envy-free allocations that are both feasible and contiguous are guaranteed to exist for up to three agents with two types of preferences, when the number of layers is two. We further devise an algorithm for computing proportional allocations for any number of agents when the number of layers is factorable to three and/or some power of two. Hadi Hosseini, Ayumi Igarashi 0001, Andrew Searns |
IJCAI | 1 |
| 2019 | Partners in Crime: Manipulating the Deferred Acceptance Algorithm through an AccompliceabstractWe introduce a new manipulation strategy available to women in the men-proposing stable matching, called manipulation through an accomplice. In this strategy, a woman can team up with a potential male “accomplice” who manipulates on her behalf to obtain a better match for her. We investigate the stability of the matching obtained after this manipulation, provide an algorithm to compute such strategies, and show its benefit compared to single-woman manipulation strategies. Theodora Bendlin, Hadi Hosseini |
AAAI | 2 |
| 2019 | Are You Game?abstractThe use of gameful activities in education has been widely celebrated in recent years as an effective pedagogical method in engaging students, exciting cognitive abilities, and promoting mastery. Despite the popularity of game-based learning, to date, little has been done to analyze the impacts of introducing such interventions on students and instructors alike. We focus on hybrid teaching strategies that blend educational games with instructional scaffolding in introductory computer science teaching. We assess the effectiveness of incorporating these teaching strategies by leveraging various empirical evaluation techniques and study their impacts from three different dimensions: students' point of view, instructors' perspective, and students' performance. In addition, we establish correlations between students' approaches to learning and game-based learning, and further discuss how learning concentration and curiosity relate to students' perception of game-based activities. Hadi Hosseini, Laurel Perweiler |
SIGCSE | 1 |
| 2019 | Inferring true voting outcomes in homophilic social networks
John A. Doucette, Alan Tsang, Hadi Hosseini, Kate Larson, Robin Cohen |
Auton. Agents Multi Agent Syst. | 3 |
| 2019 | Learning IS Child's Play: Game-Based Learning in Computer Science EducationabstractGame-based learning has received significant attention in educational pedagogy as an effective way of increasing student motivation and engagement. The majority of the work in this area has been focused on digital games or games involving technology. We focus on the use of traditional game design in improving student engagement and perception of learning in teaching computer science concepts in higher education. In addition, as part of an interdisciplinary effort, we discuss the interplay between game-based learning in higher education and disciplinary cultures, addressing the lack of empirical evidence on the impact of game design on learning outcomes, engagement, and students’ perception of learning. Hadi Hosseini, Maxwell Hartt, Mehrnaz Mostafapour |
ACM Trans. Comput. Educ. | 1 |
| 2018 | Investigating the characteristics of one-sided matching mechanisms under various preferences and risk attitudes
Hadi Hosseini, Kate Larson, Robin Cohen |
Auton. Agents Multi Agent Syst. | 1 |
| 2016 | A Framework for the Game-theoretic Analysis of Censorship ResistanceabstractAbstract We present a game-theoretic analysis of optimal solutions for interactions between censors and censorship resistance systems (CRSs) by focusing on the data channel used by the CRS to smuggle clients’ data past the censors. This analysis leverages the inherent errors (false positives and negatives) made by the censor when trying to classify traffic as either non-circumvention traffic or as CRS traffic, as well as the underlying rate of CRS traffic. We identify Nash equilibrium solutions for several simple censorship scenarios and then extend those findings to more complex scenarios where we find that the deployment of a censorship apparatus does not qualitatively change the equilibrium solutions, but rather only affects the amount of traffic a CRS can support before being blocked. By leveraging these findings, we describe a general framework for exploring and identifying optimal strategies for the censorship circumventor, in order to maximize the amount of CRS traffic not blocked by the censor. We use this framework to analyze several scenarios with multiple data-channel protocols used as cover for the CRS. We show that it is possible to gain insights through this framework even without perfect knowledge of the censor’s (secret) values for the parameters in their utility function. Tariq Elahi, John A. Doucette, Hadi Hosseini, Steven J. Murdoch, Ian Goldberg 0001 |
Proc. Priv. Enhancing Technol. | 3 |
| 2015 | Matching with Dynamic Ordinal PreferencesabstractWe consider the problem of repeatedly matching a set of alternatives to a set of agents with dynamic ordinal preferences. Despite a recent focus on designing one-shot matching mechanisms in the absence of monetary transfers, little study has been done on strategic behavior of agents in sequential assignment problems. We formulate a generic dynamic matching problem via a sequential stochastic matching process. We design a mechanism based on random serial dictatorship (RSD) that, given any history of preferences and matching decisions, guarantees global stochastic strategyproofness while satisfying desirable local properties. We further investigate the notion of envyfreeness in such sequential settings. Hadi Hosseini, Kate Larson, Robin Cohen |
AAAI | 1 |
| 2015 | On Manipulablity of Random Serial Dictatorship in Sequential Matching with Dynamic PreferencesabstractWe consider the problem of repeatedly matching a set of alternatives to a set of agents in the absence of monetary transfer. We propose a generic framework for evaluating sequential matching mechanisms with dynamic preferences, and show that unlike single-shot settings, the random serial dictatorship mechanism is manipulable. Hadi Hosseini, Kate Larson, Robin Cohen |
AAAI | 1 |
| 2015 | Characterization and Computation of Equilibria for Indivisible Goods
Simina Brânzei, Hadi Hosseini, Peter Bro Miltersen |
SAGT | 2 |
| 2012 | Dynamic Multiagent Resource Allocation: Integrating Auctions and MDPs for Real-Time DecisionsabstractMultiagent resource allocation under uncertainty raises various computational challenges in terms of efficiency such as intractability, communication cost, and preference representation. To date most approaches do not provide efficient solutions for dynamic environments where temporal constraints pose particular challenges. We propose two techniques to cope with such settings: auctions to allocate fairly according to preferences, and MDPs to address stochasticity. This research seeks to determine the ideal combination between the two methods to handle wide range of allocation problems with reduced computation and communication cost between agents. Hadi Hosseini |
AAAI | 1 |
| 2012 | A Market-Based Coordination Mechanism for Resource Planning Under UncertaintyabstractMultiagent Resource Allocation (MARA) distributes a set of resources among a set of intelligent agents in order to respect the preferences of the agents and to maximize some measure of global utility, which may include minimizing total costs or maximizing total return. We are interested in MARA solutions that provide optimal or close-to-optimal allocation of resources in terms of maximizing a global welfare function with low communication and computation cost, with respect to the priority of agents, and temporal dependencies between resources. We propose an MDP approach for resource planning in multiagent environments. Our approach formulates internal preference modeling and success of each individual agent as a single MDP and then to optimize global utility, we apply a market-based solution to coordinate these decentralized MDPs. Hadi Hosseini, Jesse Hoey, Robin Cohen |
AAAI | 1 |
| 2009 | An Autonomous Agent-based Framework for Self-Healing Power GridabstractReliable, secure and robust power grid network is a necessity for crucial financial, industrial and business networks. Since national electrical grid, telecommunication, information networks and transportation networks are interdependent critical infrastructures, having an agent-based self-healing framework to reduce cascading failures through the networks and finding reasonable solution for potential faults - would be an essential asset. In response to this need we propose a self-healing framework that employs advanced failure diagnosis techniques along with autonomous Web services to provide temporary recovery solutions. Furthermore, it provides a cognitive planning cycle to find ultimate corrective solutions as well as evaluation service to verify the effectiveness and performance of the final solution. Zeinab Noorian, Hadi Hosseini, Mihaela Ulieru |
SMC | 2 |