Managing Conversation Uncertainty in TutorJ

Uncertainty in natural language dialogue is often treated through stochastic models. Some of the authors already presented TutorJ mat is an Intelligent Tutoring System, whose interaction with the user is very intensive, and makes use of both dialogic and graphical modality. When managing the interaction, the system needs to cope with uncertainty due to the understanding of the user's needs and wishes. In this paper we present the extended version of TutorJ, focusing on the new features added to its chatbot module. These features allow to merge deterministic and probabilistic reasoning in dialogue management, and in writing the rules of the system's procedural memory

Improving Assessment of Students through Semantic Space Construction

Assessment is one of the hardest tasks an Intel- ligent Tutoring System has to perform. It involves different and sometimes uncorrelated sub-tasks: building a student model to define her needs, defining tools and procedures to perform tests, understanding students’ replies to system prompts, defining suitable procedures to evaluate the correctness of students’ replies, and strategies to improve students’ abilities after the assessment session. In this work we present an improvement of our system, TutorJ, with particular attention to the assessment phase. Many tutoring systems offer only a limited set of assessment options like multiple-choice questions, fill-in-the-blanks tests or other types of predefined replies obtained through graphical widgets (radio-buttons, text-areas). This limited set of solutions makes interaction poor and unable to satisfy the users’ needs. Our interest is to enrich interaction with dialog in natural language. In this respect, the assessment problem is strictly connected to natural language understanding. The preliminary step is indeed to understand questions and replies of the student. We have reviewed the system design in the framework of a cognitive architecture with the aim to reach a double result: the reduction of the effort for the construction of the knowledge base and the improvement of the system capabilities in the assessment process. To this aim a new common semantic space has been defined and implemented. The entire architecture is oriented to intuitive and natural interaction

A meta-cognitive architecture for planning in uncertain environments

Abstract The behavior of an artificial agent performing in a natural environment is influenced by many different pressures and needs coming from both external world and internal factors, which sometimes drive the agent to reach conflicting goals. At the same time, the interaction between an artificial agent and the environment is deeply affected by uncertainty due to the imprecision in the description of the world, and the unpredictability of the effects of the agent's actions. Such an agent needs meta-cognition in terms of both self-awareness and control. Self-awareness is related to the internal conditions that may possibly influence the completion of the task, while control is oriented to performing actions that maintain the internal model of the world and the perceptions aligned. In this work, a general meta-cognitive architecture is presented, which is aimed at overcoming these problems. The proposed architecture describes an artificial agent, which is capable to combine cognition and meta-cognition to solve problems in an uncertain world, while reconciling opposing requirements and goals. While executing a plan, such an agent reflects upon its actions and how they can be affected by its internal conditions, and starts a new goal setting process to cope with unforeseen changes. The work defines the concept of "believability" as a generic uncertain quantity, the operators to manage believability, and provides the reader with the u-MDP that is a novel MDP able to deal with uncertain quantities expressed as possibility, probability, and fuzziness. A couple u-MDPs are used to implement the agent's cognitive and meta-cognitive module. The last one is used to perceive both the physical resources of the agent's embodiment and the actions performed by the cognitive module in order to issue goal setting and re-planning actions

Automatic generation of user interfaces using the set description language

We present a paradigm to generate automatically graphical user interfaces from a formal description of the data model following the well-known model-view-control paradigm. This paradigm provide complete separation between data model and interface description, setting the programmer free from the low-level aspects of programming interfaces, letting him take care of higher level aspects. The interface along with the data model is described by means of a formal language, the Set Description Language. We also describe the infrastructure based on this paradigm we implemented to generate graphical user interfaces for generic applications. Moreover, it can adapt the user interface of a program to the needs derived from the type of data managed by the user from time to time

Illumination Correction on Biomedical Images

RF-Inhomogeneity Correction (aka bias) artifact is an important research field in Magnetic Resonance Imaging (MRI). Bias corrupts MR images altering their illumination even though they are acquired with the most recent scanners. Homomorphic Unsharp Masking (HUM) is a filtering technique aimed at correcting illumination inhomogeneity, but it produces a halo around the edges as a side effect. In this paper a novel correction scheme based on HUM is proposed to correct the artifact mentioned above without introducing the halo. A wide experimentation has been performed on MR images. The method has been tuned and evaluated using the simulated Brainweb image database. In this framework, the approach has been compared successfully against the Guillemaud filter and the SPM2 method. Moreover, the method has been successfully applied on several real MR images of the brain (0.18 T, 1.5 T and 7 T). The description of the overall technique is reported along with the experimental results that show its effectiveness in different anatomical regions and its ability to compensate both underexposed and overexposed areas. Our approach is also effective on non-radiological images, like retinal ones

GAIML: A New Language for Verbal and Graphical Interaction in Chatbots

Natural and intuitive interaction between users and complex systems is a crucial research topic in human-computer interaction. A major direction is the definition and implementation of systems with natural language understanding capabilities. The interaction in natural language is often performed by means of systems called chatbots. A chatbot is a conversational agent with a proper knowledge base able to interact with users. Chatbots appearance can be very sophisticated with 3D avatars and speech processing modules. However the interaction between the system and the user is only performed through textual areas for inputs and replies. An interaction able to add to natural language also graphical widgets could be more effective. On the other side, a graphical interaction involving also the natural language can increase the comfort of the user instead of using only graphical widgets. In many applications multi-modal communication must be preferred when the user and the system have a tight and complex interaction. Typical examples are cultural heritages applications (intelligent museum guides, picture browsing) or systems providing the user with integrated information taken from different and heterogenous sources as in the case of the iGoogle™ interface. We propose to mix the two modalities (verbal and graphical) to build systems with a reconfigurable interface, which is able to change with respect to the particular application context. The result of this proposal is the Graphical Artificial Intelligence Markup Language (GAIML) an extension of AIML allowing merging both interaction modalities. In this context a suitable chatbot system called Graphbot is presented to support this language. With this language is possible to define personalized interface patterns that are the most suitable ones in relation to the data types exchanged between the user and the system according to the context of the dialogue

CHILab @ HaSpeeDe 2: Enhancing Hate Speech Detection with Part-of-Speech Tagging

The present paper describes two neural network systems used for Hate Speech Detection tasks that make use not only of the pre-processed text but also of its Part-of-Speech (PoS) tag. The first system uses a Transformer Encoder block, a relatively novel neural network architecture that arises as a substitute for recurrent neural networks. The second system uses a Depth-wise Separable Convolutional Neural Network, a new type of CNN that has become known in the field of image processing thanks to its computational efficiency. These systems have been used for the participation to the HaSpeeDe 2 task of the EVALITA 2020 workshop with CHILab as the team name, where our best system, the one that uses Transformer, ranked first in two out of four tasks and ranked third in the other two tasks. The systems have also been tested on English, Spanish and German languages