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Bridging the Gap Between Computational Narrative and Natural Language Processing

AAAI Conferences

From Young 2010), frames (Zhu and Ontañón 2014), plotpoints early games like Zork, to the text-based interactive Victorian (Weyhrauch and Bates 1997; Nelson and Mateas 2005; dramas generated by Versu (Evans and Short 2014) Sharma et al. 2010) or social models (McCoy et al. 2011), to 3D RPG games like Skyrim (Ruch 2011), the quality of the problem of how to computationally model narratives the stories play a crucial role in engaging the player and and story spaces remains open.


PDDL+ Planning with Temporal Pattern Databases

AAAI Conferences

The introduction of PDDL+ allowed more accurate representations of complex real-world problems of interest to the scientific community. However, PDDL+ problems are notoriously challenging to planners, requiring more advanced heuristics. We introduce the Temporal Pattern Database (TPDB), a new domain-independent heuristic technique designed for PDDL+ domains with mixed discrete/continuous behaviour, non-linear system dynamics, processes, and events. The pattern in the TPDB is obtained through an abstraction based on time and state discretisation. Our approach combines constraint relaxation and abstraction techniques, and uses solutions to the relaxed problem, as a guide to solving the concrete problem with a discretisation fine enough to satisfy the continuous model's constraints.


Crowdsourcing Multimodal Dialog Interactions: Lessons Learned from the HALEF Case

AAAI Conferences

The advent of multiple study on crowdsourcing for speech applications concluded crowdsourcing vendors and software infrastructure has that "although the crowd sometimes approached the level greatly helped this effort. Several providers also offer integrated of the experts, it never surpassed it" (Parent and Eskenazi filtering tools that allow users to customize different 2011)). This is exacerbated during multimodal dialog data aspects of their data collection, including target population, collections, where it becomes harder to quality-control for geographical location, demographics and sometimes usable audio-video data, due to a variety of factors including even education level and expertise. Managed crowdsourcing poor visual quality caused by variable lighting, position, providers extend these options by offering further customization or occlusions, participant or administrator error, or technical and end-to-end management of the entire data issues with the system or network (McDuff, Kaliouby, and collection operation.


Households, The Homeless and Slums Towards a Standard for Representing City Shelter Open Data

AAAI Conferences

In order to compare and analyse open data across cities, standard representations or ontologies have to be created. This paper defines a shelter ontology that includes concepts of shelters, slums, households and homelessness. The design of the ontology is based upon the data requirements of ISO 37120. ISO 37120 defines 100 indicators to measure and compare city performance. There are three shelter-themed indicators defined, namely 15.1 Percentage of city population living in slums, 15.2 Number of homeless per 100 000 population, and 15.3 Percentage of households that exist without registered legal titles. This ontology enables both the representation of the ISO 37120 Shelter theme indicators' definitions, and a city's indicator values and supporting data. This enables the analysis of city indicators by intelligent agents.


Back to the Past: Ancient Games as a New AI Frontier

AAAI Conferences

This short note proposes the study of ancient games as a new frontier for game AI research. This aspect of games research has been largely neglected so far from an AI perspective, but could benefit significantly from the application of modern computational techniques.


AI as Evaluator: Search Driven Playtesting of Modern Board Games

AAAI Conferences

This paper presents a demonstration of how AI can be useful in the game design and development process of a modern board game. By using an artificial intelligence algorithm to play a substantial amount of matches of the Ticket to Ride board game and collecting data, we can analyze several features of the gameplay as well as of the game board. Results revealed loopholes in the game's rules and pointed towards trends in how the game is played. We are then led to the conclusion that large scale simulation utilizing artificial intelligence can offer valuable information regarding modern board games and their designs that would ordinarily be prohibitively expensive or time-consuming to discover manually.


Monitoring Plan Optimality Using Landmarks and Domain-Independent Heuristics

AAAI Conferences

When acting, agents may deviate from the optimal plan, either because they are not perfect optimizers or because they interleave multiple unrelated tasks. In this paper, we detect such deviations by analyzing a set of observations and a monitored goal to determine if an observed agent's actions contribute towards achieving the goal. We address this problem without pre-defined static plan libraries, and instead use a planning domain definition to represent the problem and the expected agent behavior. At the core of our approach, we exploit domain-independent heuristics for estimating the goal distance, incorporating the concept of landmarks (actions which all plans must undertake if they are to achieve the goal). We evaluate the resulting approach empirically using several known planning domains, and demonstrate that our approach effectively detects such deviations.


Hybrid Activity and Plan Recognition for Video Streams

AAAI Conferences

Computer-based human activity recognition of daily living has recently attracted much interest due to its applicability to ambient assisted living. Such applications require the automatic recognition of high-level activities composed of multiple actions performed by human beings in an environment. In this work, we address the problem of activity recognition in an indoor environment, focusing on a kitchen scenario. Unlike existing approaches that identify single actions from video sequences, we also identify the goal towards which the subject of the video is pursuing. Our hybrid approach combines a deep learning architecture to analyze raw video data and identify individual actions which are then processed by a goal recognition algorithm that uses a plan library describing possible overarching activities to identify the ultimate goal of the subject in the video. Experiments show that our approach achieves the state-of-the-art for identifying cooking activities in a kitchen scenario.


Using Options to Accelerate Learning of New Tasks According to Human Preferences

AAAI Conferences

Over the years, people need to incorporate a wider range of information and multiple objectives for their decision making. Nowadays, humans are dependent on computer systems to interpret and take profit from the huge amount of available data on the Internet. Hence, varied services, such as location-based systems, must combine a huge quantity of raw data to give the desired response to the user. However, as humans have different preferences, the optimal answer is different for each user profile, and few systems offer the service of solving tasks in a customized manner for each user. Reinforcement Learning (RL) has been used to autonomously train systems to solve (or assist on) decision-making tasks according to user preferences. However, the learning process is very slow and require many interactions with the environment. Therefore, we here propose to reuse knowledge from previous tasks to accelerate the learning process in a new task. Our proposal, called Multiobjective Options, accelerates learning while providing a customized solution according to the current user preferences. Our experiments in the Tourist World Domain show that our proposal learns faster and better than regular learning, and that the achieved solutions follow user preferences.


Parallel Chromatic MCMC with Spatial Partitioning

AAAI Conferences

We introduce a novel approach for parallelizing MCMC inference in models with spatially determined conditional independence relationships, for which existing techniques exploiting graphical model structure are not applicable. Our approach is motivated by a model of seismic events and signals, where events detected in distant regions are approximately independent given those in intermediate regions. We perform parallel inference by coloring a factor graph defined over regions of latent space, rather than individual model variables. Evaluating on a model of seismic event detection, we achieve significant speedups over serial MCMC with no degradation in inference quality.