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Using Lanchester Attrition Laws for Combat Prediction in StarCraft

AAAI Conferences

Smart decision making at the tactical level is important for Artificial Intelligence (AI) agents to perform well in the domain of real-time strategy (RTS) games. Winning battles is crucial in RTS games, and while humans can decide when and how to attack based on their experience, it is challenging for AI agents to estimate combat outcomes accurately. A few existing models address this problem in the game of StarCraft but present many restrictions, such as not modeling injured units, supporting only a small number of unit types, or being able to predict the winner of a fight but not the remaining army. Prediction using simulations is a popular method, but generally slow and requires extensive coding to model the game engine accurately. This paper introduces a model based on Lanchester's attrition laws which addresses the mentioned limitations while being faster than running simulations. Unit strength values are learned using maximum likelihood estimation from past recorded battles. We present experiments that use a StarCraft simulator for generating battles for both training and testing, and show that the model is capable of making accurate predictions. Furthermore, we implemented our method in a StarCraft bot that uses either this or traditional simulations to decide when to attack or to retreat. We present tournament results (against top bots from 2014 AIIDE competition) comparing the performances of the two versions, and show increased winning percentages for our method.


Flexible Reward Plans to Elicit Truthful Predictions in Crowdsourcing

AAAI Conferences

We develop a flexible reward plan to elicit truthful predictive probability distribution over a set of uncertain events from workers.ย  In our reward plan, the principal can assign rewards for incorrect predictions according to her similarity between events.ย  In the spherical proper scoring rule, a worker's expected utility is represented as the inner product of her truthful predictive probability and her declared probability. We generalize the inner product by introducing a reward matrix that defines a reward for each prediction-outcome pair. We show that if the reward matrix is symmetric and positive definite, the spherical proper scoring rule guarantees the maximization of a worker's expected utility when she truthfully declares her prediction.


Extracting Structured Information via Automatic + Human Computation

AAAI Conferences

We present a system for extracting structured information from unstructured text using a combination of information retrieval, natural language processing, machine learning, and crowdsourcing. We test our pipeline by building a structured database of gun violence incidents in the United States. The results of our pilot study demonstrate that the proposed methodology is a viable way of collecting large-scale, up-to-date data for public health, public policy, and social science research.


LoRUS: A Mobile Crowdsourcing System for Efficiently Retrieving the Top-k Relevant Users in a Spatial Window

AAAI Conferences

Hence, they do not address mobile resource devices, it has now become practically feasible to enable constraints (e.g., energy, bandwidth) and also result in unnecessary people to share information about dynamic events (e.g., trees spam. On the other hand, multi-cast approaches randomly fallen on roads due to a storm, sudden truck breakdowns send the queries to some of the users to preserve mobile and unscheduled processions) in their current location. This resources, but they do not ensure the direction of queries strongly motivates facilitation of various kinds of locationdependent to the most relevant users.


Acquiring Planning Knowledge via Crowdsourcing

AAAI Conferences

Plan synthesis often requires complete domain models and initial states as input. In many real world applications, it is difficult to build domain models and provide complete initial state beforehand. In this paper we propose to turn to the crowd for help before planning. We assume there are annotators available to provide information needed for building domain models and initial states. However, there might be a substantial amount of discrepancy within the inputs from the crowd. It is thus challenging to address the planning problem with possibly noisy information provided by the crowd. We address the problem by two phases. We first build a set of Human Intelligence Tasks (HITs), and collect values from the crowd. We then estimate the actual values of variables and feed the values to a planner to solve the problem.


Combining Crowd and Expert Labels Using Decision Theoretic Active Learning

AAAI Conferences

We consider a finite-pool data categorization scenario which requires exhaustively classifying a given set of examples with a limited budget. We adopt a hybrid human-machine approach which blends automatic machine learning with human labeling across a tiered workforce composed of domain experts and crowd workers. To effectively achieve high-accuracy labels over the instances in the pool at minimal cost, we develop a novel approach based on decision-theoretic active learning. On the important task of biomedical citation screening for systematic reviews, results on real data show that our method achieves consistent improvements over baseline strategies. To foster further research by others, we have made our data available online.


Guardian: A Crowd-Powered Spoken Dialog System for Web APIs

AAAI Conferences

Natural language dialog is an important and intuitive way for people to access information and services. However, current dialog systems are limited in scope, brittle to the richness of natural language, and expensive to produce. This paper introduces Guardian, a crowd-powered framework that wraps existing Web APIs into immediately usable spoken dialog systems. Guardian takes as input the Web API and desired task, and the crowd determines the parameters necessary to complete it, how to ask for them, and interprets the responses from the API. The system is structured so that, over time, it can learn to take over for the crowd. This hybrid systems approach will help make dialog systems both more general and more robust going forward.


Reliable Aggregation of Boolean Crowdsourced Tasks

AAAI Conferences

We propose novel algorithms for the problem of crowdsourcing binary labels. Such binary labeling tasks are very common in crowdsourcing platforms, for instance, to judge the appropriateness of web content or to flag vandalism. We propose two unsupervised algorithms: one simple to implement albeit derived heuristically, and one based on iterated bayesian parameter estimation of user reputation models. We provide mathematical insight into the benefits of the proposed algorithms over existing approaches, and we confirm these insights by showing that both algorithms offer improved performance on many occasions across both synthetic and real-world datasets obtained via Amazon Mechanical Turk.


Assistive Technologies for People With Cognitive Disabilities: Challenges and Possibilities

AAAI Conferences

According to the Journal, Inclusion, in 2012, 9% of the US population, or 28.5M Americans, had a cognitive disability. Worldwide the number is believed to exceed 630 million. This is a very heterogeneous group, with a wide variety of abilities and impairments making it challenging to develop assistive technologies to meet their needsA growing sub-set of this cohort is the aging population, who continue to work but experience mild cognitive changes. Though these these individuals have deep funds of knowledge, and valuable skills they may struggle in the workplace, in part due to lack of access to tools that can address their individual challenges. . The development of new technologies, such as cognitive assistants, has opened the door to more useful solutions. This paper will review the history and challenges of assistive technology for cognition (ATC) and highlight the work in which we are currently engaged.


Merits of a Temporal Modal Logic for Narrative Discourse Generation

AAAI Conferences

Just as there exists varied uses for computational models of narrative, there exists a wide variety of languages aimed at representing stories. A number of them have historic roots in automated generation, for which these languages have to be limited in order to make the generation process computationally feasible. Other are focused on story understanding, with close ties to natural language making many reasoning processes computationally intractable. In this paper, we discuss the trade-off between expressivity and computational complexity of the reasoning process and argue that Impulse, a temporal, modal logic provides more expressivity than languages historically associated with story generation, while still affording reasoning capabilities. We show that these properties enable certain aspects of narrative discourse generation by using two examples from different genres, and claim that this generalizes to a broader class of problems.