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Semantic Data Modeling For Fun and Profit

@machinelearnbot

Data modeling is usually one of those subjects that make people's eyes glaze over. It's not really programming, though understanding programming concepts such as objects, inheritance, polymorphism and similar multisyllabic words is usually helpful to do modeling. Perhaps the best way of thinking about modeling is to see it as a way to describe a business in clearly defined pieces. From a business perspective, if done right, data modeling can prove quite valuable. When done badly, modeling can prove worse than useless, since a big part of the value of modeling is to employ it to make predictions.


Ontology for Data Science

@machinelearnbot

When I returned to university to do a graduate degree, I was interested to discover how certain terms are subject to "intellectual interpretation." A word that I was asked to explain during one of my earliest classes was "ontology." Since this term was absent from my dictionary, I originally confused it with "oncology." I faintly recall that oncology involves the study of tumors. After consulting a few sources, I said that ontology is the study of how things come to exist or into being. I came across another perspective although I don't recall the source: ontology is the study of how things gain relevance or become recognized, indicating that existence can be regarded as a matter of recognition. Perhaps there is no monopoly on the exact meaning. However, I would say of ontology in relation to data science, it explains how meaning is attached to data and therefore how that data gains and retains meaning. For example, if I were asked to count the number of trucks in a parking lot, it isn't obvious what should be included: small pick-ups, tow-trucks, commercial hauling vehicles, dump trucks, and maybe heavy construction trucks.


Information-theoretic Interestingness Measures for Cross-Ontology Data Mining

arXiv.org Artificial Intelligence

Community annotation of biological entities with concepts from multiple bio-ontologies has created large and growing repositories of ontology-based annotation data with embedded implicit relationships among orthogonal ontologies. Development of efficient data mining methods and metrics to mine and assess the quality of the mined relationships has not kept pace with the growth of annotation data. In this study, we present a data mining method that uses ontology-guided generalization to discover relationships across ontologies along with a new interestingness metric based on information theory. We apply our data mining algorithm and interestingness measures to datasets from the Gene Expression Database at the Mouse Genome Informatics as a preliminary proof of concept to mine relationships between developmental stages in the mouse anatomy ontology and Gene Ontology concepts (biological process, molecular function and cellular component). In addition, we present a comparison of our interestingness metric to four existing metrics. Ontology-based annotation datasets provide a valuable resource for discovery of relationships across ontologies. The use of efficient data mining methods and appropriate interestingness metrics enables the identification of high quality relationships.


The Art of Modeling Names

@machinelearnbot

This is the first in a series about cross format data modeling principles. In the data modeling realm, there is perhaps no example that is as ubiquitous as modelling personal names. After all, things don't get much simpler than a name: This isn't really a model, but rather an instance of a model - an actual example that proves out the model. There are, however, a number of ways that such a model can be described. What you see is a set of assertions that identify that there exists a class named "person", and that this class has two properties.


Hybrid of Qualitative and Quantitative Knowledge Models for Solving Physics Word Problems

AAAI Conferences

This paper describes a system that uses a hybrid of quantitative and qualitative knowledge to solve physics word problems. Such an integration of knowledge from two models is useful to come up with the correct solution for many of these problems. We have applied this hybrid model to solve word problems from projectile motion. These types of word problems have not been addressed in recent times. We have solved a set of 30 problems in this domain.


An Ontology-Based Mobile Application for Task Managing in Collaborative Groups

AAAI Conferences

This paper presents an ontology-based application for mobile devices which is responsible for supporting groups of people with the management of their shared tasks. The ontology stores the domain knowledge about collaborative tasks, which is used to support task recognition and relocation. Such knowledge is used by a multi-agent system that consists of a group of agents representing each person in the group. The agents use plan recognition techniques to monitor the execution of tasks according to the schedules and negotiate task allocation when needed. Our techniques have been applied in a healthcare scenario which consists of a family group that takes care of an elderly person. This paper presents an ontology-based application for mobile devices which is responsible for supporting groups of people with the management of their shared tasks. % in a healthcare scenario.The ontology stores the domain knowledge about collaborative tasks, which is used to support task recognition and relocation.Such knowledge is used by a multi-agent system that consists of a group of agents representing each person in the group.The agents use plan recognition techniques to monitor the execution of tasks according to the schedules and negotiate task allocation when needed.Our techniques have been applied in a healthcare scenario which consists of a family group that takes care of an elderly person.


Machine Learning Ontology

#artificialintelligence

Instead of seeing each Machine Learning (ML) method as a "shiny new object", here is an attempt to create a unified picture. There is no consensus when it comes to an ontology for ML methods; organizational principles are simply ways to get our arms around knowledge so that we are not swamped by too many unconnected notions. A powerful organization of the concepts or Ontology of ML is based on conditional expectation. Conditional Expectation of Class'y' given input attributes, x, denoted by E[y x]. Implementation of estimation of the conditional expectation with various assumptions lead, one way or the other, to ALL the ML techniques that we have today in 2016.


Linked Data meets Data Science

@machinelearnbot

As a long-term member of the Linked Data community, which has evolved from W3C's Semantic Web, the latest developments around Data Science have become more and more attractive to me due to its complementary perspectives on similar challenges. When taking a closer look to the approaches taken by those two'schools of advanced data management' one aspect becomes obvious: Both try to develop models in order to be able to'codify and to calculate the data soup'. While Linked Data technologies are built on top of knowledge models ('ontologies'), which try to describe first of all data in distributed environments like the web, are Data Science methods mainly based on statistical models. One could say: 'Causality and Reasoning over Distributed Data' meets'Correlation and Machine Learning on Big Data'. In contrast to this supposed contradiction, correlations and complementarities between those two disciplines prevail.


Expressive Description Logic with Instantiation Metamodelling

AAAI Conferences

We investigate a higher-order extension of the description logic (DL) SROIQ that provides a fixedly interpreted role semantically coupled with instantiation. It is useful to express interesting meta-level constraints on the modelled ontology. We provide a model-theoretic characterization of the semantics, and we show the decidability by means of reduction.


Minimality Postulates for Ontology Revision

AAAI Conferences

In many scenarios where the integration of information into a knowledge base (KB) leads to inconsistencies there is a need to change the KB minimally. In belief revision, relevance postulates meet the minimality requirement by restricting the elimination of KB elements to those that are relevant for the incoming information. This paper focuses on two minimality postulates in an ontology revision scenario in which conflicts are caused by ambiguous use of symbols: a relevance postulate and a generalized inclusion postulate which limits the creativity of the operators. Both postulates exploit the (satisfiably) equivalent representation of a first-order logic KB by its prime implicates, which, intuitively, represent the most atomic logical components of the KB. The paper shows that reinterpretation operators (which are ontology revision operators) fulfill both postulates.