no code implementations • 24 Jan 2024 • Hana Chockler, Joseph Y. Halpern
We focus on explaining image classifiers, taking the work of Mothilal et al. [2021] (MMTS) as our point of departure.
no code implementations • 17 Jan 2024 • Joseph Y. Halpern, Evan Piermont
We show that it is possible to understand and identify a decision maker's subjective causal judgements by observing her preferences over interventions.
no code implementations • 31 Dec 2023 • Joseph Y. Halpern
A definition of what counts as an explanation of mathematical statement, and when one explanation is better than another, is given.
1 code implementation • 9 Nov 2023 • Oliver E. Richardson, Joseph Y. Halpern, Christopher De Sa
Probabilistic dependency graphs (PDGs) are a flexible class of probabilistic graphical models, subsuming Bayesian Networks and Factor Graphs.
no code implementations • 13 Mar 2023 • Meir Friedenberg, Joseph Y. Halpern
For over 25 years, common belief has been widely viewed as necessary for joint behavior.
no code implementations • 17 Jan 2023 • Sander Beckers, Joseph Y. Halpern, Christopher Hitchcock
The goal of this paper is to extend standard causal models to allow for constraints on settings of variables.
no code implementations • 11 Oct 2022 • Sander Beckers, Hana Chockler, Joseph Y. Halpern
In this paper we formally define a qualitative notion of harm that uses causal models and is based on a well-known definition of actual causality (Halpern, 2016).
no code implementations • 29 Sep 2022 • Sander Beckers, Hana Chockler, Joseph Y. Halpern
In a companion paper (Beckers et al. 2022), we defined a qualitative notion of harm: either harm is caused, or it is not.
no code implementations • 15 Jun 2022 • Valerio Capraro, Joseph Y. Halpern, Matjaz Perc
We review the literature on models that try to explain human behavior in social interactions described by normal-form games with monetary payoffs.
no code implementations • 25 Jan 2022 • Joseph Y. Halpern, Yuval Heller, Eyal Winter
We study the strategic advantages of coarsening one's utility by clustering nearby payoffs together (i. e., classifying them the same way).
no code implementations • 26 Dec 2021 • Joseph Y. Halpern, Arnon Lotem
The brain in our abstract model is a network of nodes and edges.
no code implementations • 21 Dec 2021 • Joseph Y. Halpern, Spencer Peters
Generalized structural equations models (GSEMs) [Peters and Halpern 2021], are, as the name suggests, a generalization of structural equations models (SEMs).
no code implementations • 16 Dec 2021 • Spencer Peters, Joseph Y. Halpern
Structural-equations models (SEMs) are perhaps the most commonly used framework for modeling causality.
no code implementations • 2 Apr 2021 • Matvey Soloviev, Joseph Y. Halpern
We moreover revisit some design decisions of the HP framework that were made with non-nested causal statements in mind, such as the choice to treat specific values of causal variables as opposed to the variables themselves as causes, and may no longer be appropriate for nested ones.
no code implementations • 6 Jul 2020 • Joseph Y. Halpern, Evan Piermont
We investigate how to model the beliefs of an agent who becomes more aware.
no code implementations • 30 Jun 2020 • Xinming Liu, Joseph Y. Halpern
While traditional economics assumes that humans are fully rational agents who always maximize their expected utility, in practice, we constantly observe apparently irrational behavior.
no code implementations • 20 May 2020 • Meir Friedenberg, Joseph Y. Halpern
In this work we show how causal models can be combined in cases where the experts might disagree on the causal structure for variables that appear in both models due to having different focus areas.
no code implementations • 20 May 2020 • Dalal Alrajeh, Hana Chockler, Joseph Y. Halpern
We formally define the notion of an effective intervention, and then consider how experts' causal judgments can be combined in order to determine the most effective intervention.
no code implementations • 20 May 2020 • Matvey Soloviev, Joseph Y. Halpern
We introduce a theoretical model of information acquisition under resource limitations in a noisy environment.
no code implementations • 20 May 2020 • Nan Rong, Joseph Y. Halpern, Ashutosh Saxena
Doing this results in a family of systems, each of which has an extremely large action space, although only a few actions are "interesting".
no code implementations • 20 May 2020 • Natasha Alechina, Joseph Y. Halpern, Brian Logan
Many objectives can be achieved (or may be achieved more effectively) only by a group of agents executing a team plan.
no code implementations • 30 Sep 2019 • Joseph Y. Halpern
This is a review of "The Book of Why", by Judea Pearl.
no code implementations • 22 Jul 2019 • Joseph Y. Halpern, Rafael Pass
In earlier work, we gave a characterization of iterated admissibility using an "all I know" operator, that captures the intuition that "all the agent knows" is that agents satisfy the appropriate rationality assumptions.
no code implementations • 27 Jun 2019 • Sander Beckers, Frederick Eberhardt, Joseph Y. Halpern
Abstract descriptions can provide the basis for interventions on the system and explanation of observed phenomena at a level of granularity that is coarser than the most fundamental account of the system.
no code implementations • 11 Mar 2019 • Meir Friedenberg, Joseph Y. Halpern
We provide a formal definition of blameworthiness in settings where multiple agents can collaborate to avoid a negative outcome.
no code implementations • 10 Dec 2018 • Sander Beckers, Joseph Y. Halpern
We consider a sequence of successively more restrictive definitions of abstraction for causal models, starting with a notion introduced by Rubenstein et al. (2017) called exact transformation that applies to probabilistic causal models, moving to a notion of uniform transformation that applies to deterministic causal models and does not allow differences to be hidden by the "right" choice of distribution, and then to abstraction, where the interventions of interest are determined by the map from low-level states to high-level states, and strong abstraction, which takes more seriously all potential interventions in a model, not just the allowed interventions.
no code implementations • 13 Oct 2018 • Joseph Y. Halpern, Max Kleiman-Weiner
We provide formal definitions of degree of blameworthiness and intention relative to an epistemic state (a probability over causal models and a utility function on outcomes).
no code implementations • 27 Jul 2017 • Joseph Y. Halpern, Ron van der Meyden, Riccardo Pucella
We present a simple logic based on the well-understood modal operators of knowledge, time, and probability, and show that it is able to handle issues that have often been swept under the rug by other approaches, while being flexible enough to capture all the higher- level security notions that appear in BAN logic.
no code implementations • 24 Jun 2016 • Valerio Capraro, Joseph Y. Halpern
We show that by assuming translucent players, we can recover many of the regularities observed in human behavior in well-studied games such as Prisoner's Dilemma, Traveler's Dilemma, Bertrand Competition, and the Public Goods game.
no code implementations • 17 Jun 2015 • Joseph Y. Halpern
This short note discusses the role of syntax vs. semantics and the interplay between logic, philosophy, and language in computer science and game theory.
no code implementations • 1 May 2015 • Joseph Y. Halpern
The original Halpern-Pearl definition of causality [Halpern and Pearl, 2001] was updated in the journal version of the paper [Halpern and Pearl, 2005] to deal with some problems pointed out by Hopkins and Pearl [2003].
no code implementations • 3 Mar 2015 • Hans van Ditmarsch, Joseph Y. Halpern, Wiebe van der Hoek, Barteld Kooi
This chapter provides an introduction to some basic concepts of epistemic logic, basic formal languages, their semantics, and proof systems.
no code implementations • 31 Jan 2015 • Joseph Y. Halpern, Samantha Leung
The menu-dependent nature of regret-minimization creates subtleties when it is applied to dynamic decision problems.
no code implementations • 11 Dec 2014 • Joseph Y. Halpern
It is also shown that, by adding extra variables, a modification to the original HP definition made to deal with an example of Hopkins and Pearl may not be necessary.
no code implementations • 9 Dec 2014 • Joseph Y. Halpern
Roughly speaking, the degree of blame of A for B is the expected degree of responsibility of A for B, taken over the epistemic state of an agent.
no code implementations • 9 Dec 2014 • Gadi Aleksandrowicz, Hana Chockler, Joseph Y. Halpern, Alexander Ivrii
Halpern and Pearl introduced a definition of actual causality; Eiter and Lukasiewicz showed that computing whether X=x is a cause of Y=y is NP-complete in binary models (where all variables can take on only two values) and\ Sigma_2^P-complete in general models.
no code implementations • 7 Aug 2014 • Joseph Y. Halpern, Riccardo Pucella
We present a propositional logic to reason about the uncertainty of events, where the uncertainty is modeled by a set of probability measures assigning an interval of probability to each event.
no code implementations • 7 Aug 2014 • Joseph Y. Halpern
Causal models defined in terms of a collection of equations, as defined by Pearl, are axiomatized here.
no code implementations • 27 Jul 2014 • Joseph Y. Halpern, Nan Rong, Ashutosh Saxena
We define a new framework, MDPs with unawareness (MDPUs) to deal with the possibilities that a DM may not be aware of all possible actions.
no code implementations • 27 Jul 2014 • Joseph Y. Halpern
A general notion of algebraic conditional plausibility measures is defined.
no code implementations • 27 Jul 2014 • Joseph Y. Halpern, Riccardo Pucella
We introduce a logic for reasoning about evidence, that essentially views evidence as a function from prior beliefs (before making an observation) to posterior beliefs (after making the observation).
no code implementations • 27 Jul 2014 • Peter D. Grunwald, Joseph Y. Halpern
We consider how an agent should update her uncertainty when it is represented by a set P of probability distributions and the agent observes that a random variable X takes on value x, given that the agent makes decisions using the minimax criterion, perhaps the best-studied and most commonly-used criterion in the literature.
no code implementations • 27 Jul 2014 • Peter D. Grunwald, Joseph Y. Halpern
It is commonly-accepted wisdom that more information is better, and that information should never be ignored.
no code implementations • 27 Jul 2014 • Peter D. Grunwald, Joseph Y. Halpern
A criterion known as CAR (coarsening at random) in the statistical literature characterizes when ``naive' conditioning in a naive space works.
no code implementations • 27 Jul 2014 • Joseph Y. Halpern
Starting with a likelihood or preference order on worlds, we extend it to a likelihood ordering on sets of worlds in a natural way, and examine the resulting logic.
no code implementations • 27 Jul 2014 • Joseph Y. Halpern, Riccardo Pucella
Expectation is a central notion in probability theory.
no code implementations • 27 Jul 2014 • Joseph Y. Halpern, Riccardo Pucella
An agent often has a number of hypotheses, and must choose among them based on observations, or outcomes of experiments.
no code implementations • 16 Jan 2014 • Peter D. Grunwald, Joseph Y. Halpern
We consider how an agent should update her beliefs when her beliefs are represented by a set P of probability distributions, given that the agent makes decisions using the minimax criterion, perhaps the best-studied and most commonly-used criterion in the literature.
no code implementations • 9 Jan 2014 • Joseph Y. Halpern, Willemien Kets
Standard models of multi-agent modal logic do not capture the fact that information is often \emph{ambiguous}, and may be interpreted in different ways by different agents.
no code implementations • 5 Sep 2013 • Joseph Y. Halpern, Christopher Hitchcock
Judea Pearl was the first to propose a definition of actual causation using causal models.
no code implementations • 5 Sep 2013 • Joseph Y. Halpern
In this paper, a notion of comparative likelihood when uncertainty is represented by a weighted set of probability measures is defined.
no code implementations • 5 Sep 2013 • Joseph Y. Halpern, Christopher Hitchcock
Recent work in psychology and experimental philosophy has shown that judgments of actual causation are often influenced by consideration of defaults, typicality, and normality.
no code implementations • 17 Aug 2013 • Joseph Y. Halpern, Rafael Pass, Lior Seeman
There have been two major lines of research aimed at capturing resource-bounded players in game theory.
no code implementations • 27 Mar 2013 • Joseph Y. Halpern
We consider the relation between knowledge and certainty, where a fact is known if it is true at all worlds an agent considers possible and is certain if it holds with probability 1.
no code implementations • 27 Mar 2013 • Ronald Fagin, Joseph Y. Halpern
An alternate way of understanding our definition of conditional belief is provided by considering ideas from an earlier paper [Fagin and Halpern, 1989], where we connect belief functions with inner measures.
no code implementations • 10 Jan 2013 • Joseph Y. Halpern, Judea Pearl
We propose a new definition of actual causes, using structural equations to model counterfactuals. We show that the definitions yield a plausible and elegant account ofcausation that handles well examples which have caused problems forother definitions and resolves major difficulties in the traditionalaccount.
no code implementations • 14 Jun 2011 • Joseph Y. Halpern
Galles and Pearl claimed that "for recursive models, the causal model framework does not add any restrictions to counterfactuals, beyond those imposed by Lewis's [possible-worlds] framework."
no code implementations • 23 Jun 2009 • Adam J. Grove, Joseph Y. Halpern
There are several well-known justifications for conditioning as the appropriate method for updating a single probability measure, given an observation.
no code implementations • 23 Jun 2009 • Lawrence Blume, David Easley, Joseph Y. Halpern
In most contemporary approaches to decision making, a decision problem is described by a sets of states and set of outcomes, and a rich set of acts, which are functions from states to outcomes over which the decision maker (DM) has preferences.