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Simulation to answer the puzzling questions about religion

Daily Mail - Science & tech

Scientists have harnessed the power of'the Beast' to answer some of the most baffling questions about religion. The custom-built computer has developed a simulated virtual human mind capable of creating the impacts of terror on behavior - with the hopes of uncovering the truth behind why people become radicalized. The model had revealed that religious ritual observance would increase after terror-inspiring events drove people beyond a certain threshold of fear. Researches at Boston University first designed a computer simulation that predicts how many people would stay in a religion based on its strictness. It was then compared with defection rates from 18 Christian denominations.


By scanning CT scans, this AI can predict who will die in the next 5 years

#artificialintelligence

Deep learning AI could one day work as an early warning system to allow earlier medical intervention to patients. This AI will tell people when they're likely to die -- and that's a good thing. That's because scientists from the University of Adelaide in Australia have used deep learning technology to analyze the computerized tomography (CT) scans of patient organs, in what could one day serve as an early warning system to catch heart disease, cancer, and other diseases early so that intervention can take place. Using a dataset of historical CT scans, and excluding other predictive factors like age, the system developed by the team was able to predict whether patients would die within five years around 70 percent of the time. The work was described in an article published in the journal Scientific Reports.


Apple wants you to pay big for their smart speaker

#artificialintelligence

As part of yesterday's WorldWide Developer Conference (WWDC) Google launched their foray into home connectivity with the HomePad called by Apple CEO Tim Cook, "breakthrough home speaker with amazing sound and incredible intelligence that will reinvent home audio." Don't overlook the last word, in his statement, despite the desire some will have to group HomePad with voice activatedAmazon Echo and Google Home, the product really belongs in a separate category, and here's why. The HomePod is a 7-inch tall smart speaker covered in a "seamless 3D mesh" fabric It contains a four-inch subwoofer According to Apple it " uses an advanced algorithm that continuously analyzes the music and dynamically tunes the low frequencies for smooth, distortion‑free sound." This includes "seven beamforming tweeters" that possess spatial awareness and direct the sound beams throughout the room. It automatically analyzes the acoustics, adjusting the sound based on the speaker's location, and steers the music in the optimal direction. According to Tim Cook: "Just like with portable music, we want to reinvent home music."


Four things you need to know about neural networks GovInsider

#artificialintelligence

In the hit movie Avengers: Age of Ultron, the Iron Man shows the'brains' of a computer system to his colleague, the Incredible Hulk. "I mean, look at this! They're like neurons firing," the Hulk exclaims, pointing to a pulsating, blue orb which represented super baddie Ultron's consciousness. We'd like to think that's what neural networks look like too. They are a rising field of artificial intelligence, and a new trend that is coming to a government near you. Neural networks describe a computing technique that closely imitates human brain functions. "By using neural networks, we try to mimic nature's ability to learn how certain things work," Associate Professor Andy Chun from City University of Hong Kong's Department of Computer Science tells GovInsider.


Increased Privacy with Reduced Communication in Multi-Agent Planning

AAAI Conferences

Multi-agent forward search (MAFS) is a state-of-the-art privacy-preserving planning algorithm. We describe a new variant of MAFS, called multi-agent forward-backward search (MAFBS) that uses both forward and backward messages to reduce the number of messages sent and obtain new privacy properties. While MAFS requires agents to send a state s produced by an action a to all agents that can apply any action in s, MAFBS sends such messages forward only to agents that have an action that requires one of the effects of a. To achieve completeness, it sends messages backward to agents that can supply a missing precondition. This more focused message passing scheme reduces states exchanged, and requires that agents be aware only of other agents that they directly interact with, leading to agent privacy.


What Can I Not Do? Towards an Architecture for Reasoning about and Learning Affordances

AAAI Conferences

This paper describes an architecture for an agent to learn and reason about affordances. In this architecture, Answer Set Prolog, a declarative language, is used to represent and reason with incomplete domain knowledge that includes a representation of affordances as relations defined jointly over objects and actions. Reinforcement learning and decision-tree induction based on this relational representation and observations of action outcomes, are used to interactively and cumulatively (a) acquire knowledge of affordances of specific objects being operated upon by specific agents; and (b) generalize from these specific learned instances. The capabilities of this architecture are illustrated and evaluated in two simulated domains, a variant of the classic Blocks World domain, and a robot assisting humans in an office environment.


Unsupervised Classification of Planning Instances

AAAI Conferences

In this paper we introduce a novel approach for unsupervised classification of planning instances based on the recent formalism of planning programs. Our approach is inspired by structured prediction in machine learning, which aims at predicting structured information about a given input rather than a scalar value. In our case, each input is an unlabelled classical planning instance, and the associated structured information is the planning program that solves the instance. We describe a method that takes as input a set of planning instances and outputs a set of planning programs, classifying each instance according to the program that solves it. Our results show that automated planning can be successfully used to solve structured unsupervised classification tasks, and invites further exploration of the connection between automated planning and structured prediction.


Occupation Measure Heuristics for Probabilistic Planning

AAAI Conferences

For the past 25 years, heuristic search has been used to solve domain-independent probabilistic planning problems, but with heuristics that determinise the problem and ignore precious probabilistic information. To remedy this situation, we explore the use of occupation measures, which represent the expected number of times a given action will be executed in a given state of a policy. By relaxing the well-known linear program that computes them, we derive occupation measure heuristics -- the first admissible heuristics for stochastic shortest path problems (SSPs) taking probabilities into account. We show that these heuristics can also be obtained by extending recent operator-counting heuristic formulations used in deterministic planning. Since the heuristics are formulated as linear programs over occupation measures, they can easily be extended to more complex probabilistic planning models, such as constrained SSPs (C-SSPs). Moreover, their formulation can be tightly integrated into i-dual, a recent LP-based heuristic search algorithm for (constrained) SSPs, resulting in a novel probabilistic planning approach in which policy update and heuristic computation work in unison. Our experiments in several domains demonstrate the benefits of these new heuristics and approach.


A Polynomial Planning Algorithm That Beats LAMA and FF

AAAI Conferences

It has been shown recently that heuristic and width-based search can be combined to produce planning algorithms with a performance that goes beyond the state-of-the-art. Such algorithms are based on best-first width search (BFWS), a plain best-first search set with evaluations functions combined lexicographically to break ties, some of which express novelty based preferences. In BFWS(f5), for example, the evaluation function f5 weights nodes by a novelty measure, breaking ties by the number of non-achieved goals. BFWS(f5) is a best-first algorithm, and hence, it is complete but not polynomial, and its performance doesn’t match the state of the art. In this work we show, however, that incomplete versions of BFWS(f5) where nodes with novelty greater than k are pruned, are not only polynomial but have an empirical performance that is better than both BFWS(f5) and state-of-the-art planners. This is shown by considering all the international planning competition instances. This is the first time where polynomial algorithms with meaningful bounds are shown to achieve state-of-the-art performance in planning. Practical and theoretical implications of this empirical finding are briefly sketched.


Analytic Decision Analysis via Symbolic Dynamic Programming for Parameterized Hybrid MDPs

AAAI Conferences

For example, we may need to (i) perform inverse learning of the cost parameters of a multi-objective reward based on observed agent behavior; (ii) perform sensitivity analyses of policies to various parameter settings; or (iii) analyze and optimize policy performance as a function of policy parameters. When such problems have mixed discrete and continuous state and/or action spaces, this leads to parameterized hybrid MDPs (PHMDPs) that are often approximately solved via discretization, sampling, and/or local gradient methods (when optimization is involved). In this paper we combine two recent advances that allow for the first exact solution and optimization of PHMDPs. We first show how each of the aforementioned use cases can be formalized as PHMDPs, which can then be solved via an extension of symbolic dynamic programming (SDP) even when the solution is piecewise nonlinear. Secondly, we can leverage recent advances in non-convex solvers that require symbolic forms of the objective function for non-convex global optimization in (i), (ii), and (iii) using SDP to derive symbolic solutions for each PHMDP formalization. We demonstrate the efficacy and scalability of our optimal analytical framework on nonlinear examples of each of the aforementioned use cases.