DOCSLIB.ORG

Causal Inference and the Data-Fusion Problem R-450 COLLOQUIUM July 2016

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Causal Inference and the Data-Fusion Problem R-450 COLLOQUIUM July 2016 TECHNICAL REPORT PAPER Causal inference and the data-fusion problem R-450 COLLOQUIUM July 2016 Elias Bareinboima,b,1 and Judea Pearla aDepartment of Computer Science, University of California, Los Angeles, CA 90095; and bDepartment of Computer Science, Purdue University, West Lafayette, IN 47907 Edited by Richard M. Shiffrin, Indiana University, Bloomington, IN, and approved March 15, 2016 (received for review June 29, 2015) We review concepts, principles, and tools that unify current ap- Assume that the information available to us comes from an proaches to causal analysis and attend to new challenges presented observational study, in which X, Y, Z,andW are measured, and by big data. In particular, we address the problem of data fusion— samples are selected at random. We ask for conditions under piecing together multiple datasets collected under heterogeneous which the query Q can be inferred from the information conditions (i.e., different populations, regimes, and sampling meth- available, which takes the form Pðy, x, z, wÞ,whereZ and W are ods) to obtain valid answers to queries of interest. The availability of sets of observed covariates. This represents the standard task of multiple heterogeneous datasets presents new opportunities to big policy evaluation, where controlling for confounding bias is the data analysts, because the knowledge that can be acquired from major issue (Fig. 1, task 1). combined data would not be possible from any individual source Consider now Fig. 1, task 2, in which the goal is again to estimate alone. However, the biases that emerge in heterogeneous environ- the effect of the intervention doðX = xÞ but the data available to the ments require new analytical tools. Some of these biases, including investigator were collected in an experimental study in which vari- confounding, sampling selection, and cross-population biases, have able Z, more accessible to manipulation than X, is randomized. been addressed in isolation, largely in restricted parametric models. [Instrumental variables (4) are special cases of this task.] The gen- We here present a general, nonparametric framework for handling eral question in this scenario is under what conditions can ran- these biases and, ultimately, a theoretical solution to the problem of domization of variable Z be used to infer how the population data fusion in causal inference tasks. would react to interventions over X. Formally, our problem is to infer PðY = yjdoðX = xÞÞ from Pð y, x, wjdoðZ = zÞÞ. A non- causal inference | counterfactuals | external validity | selection bias | parametric solution to these two problems is presented in Policy transportability Evaluation and the Problem of Confounding. In each of the two previous tasks we assumed that a perfect he exponential growth of electronically accessible information random sample from the underlying population was drawn, which Thas led some to conjecture that data alone can replace sub- may not always be realizable. Task 3 in Fig. 1 represents a ran- stantive knowledge in practical decision making and scientific domized clinical trial conducted on a nonrepresentative sample of explorations. In this paper, we argue that traditional scientific the population. Here, the information available takes the syntactic methodologies that have been successful in the natural and bio- form Pð y, z, wjdoðX = xÞ, S = 1Þ, and possibly Pð y, x, z, wjS = 1Þ, medical sciences would still be necessary for big data applications, where S is a sample selection indicator, with S = 1 indicating albeit tasked with new challenges: to go beyond predictions and, inclusion in the sample. The challenge is to estimate the effect of using information from multiple sources, provide users with rea- interest from this imperfect sampling condition. Formally, we ask soned recommendations for actions and policies. The feasibility of when the target quantity Pð yjdoðX = xÞÞ is derivable from the meeting these challenges is demonstrated here using specific data available information (i.e., sampling-biased distributions). Sam- fusion tasks, following a brief introduction to the structural causal ple Selection Bias presents a solution to this problem. model (SCM) framework (1–3). Finally, the previous examples assumed that the population from which data were collected is the same as the one for Introduction—Causal Inference and Big Data which inference was intended. This is often not the case (Fig. 1, TheSCMframeworkinvokedinthispaper constitutes a symbiosis task 4). For example, biological experiments often use animals between the counterfactual (or potential outcome) framework of as substitutes for human subjects. Or, in a less obvious exam- Neyman, Rubin, and Robins with the econometric tradition of ple, data may be available from an experimental study that Haavelmo, Marschak, and Heckman (1). In this symbiosis, coun- took place several years ago, and the current population has terfactuals are viewed as properties of structural equations and changedinasetS of (possibly unmeasured) attributes. Our serve to formally articulate research questions of interest. Graphical task then is to infer the causal effect at the target population, = = models, on the other hand, are used to encode scientific assump- Pð yjdoðX xÞ, S sÞ from the information available, which now = = tions in a qualitative (i.e., nonparametric) and transparent language takes the form Pð y, z, wjdoðX xÞÞ and Pð y, x, z, wjS sÞ.The as well as to derive the logical ramifications of these assumptions, in second expression represents information obtainable from nonexperimental studies on the current population, where particular, their testable implications and how they shape be- = havior under interventions. S s. One unique feature of the SCM framework, essential in big data The problems represented in these archetypal examples are applications, is the ability to encode mathematically the method by known as confounding bias (Fig. 1, tasks 1 and 2), sample selection which data are acquired, often referred to generically as the “de- bias(Fig.1,task3), and transportability bias (Fig. 1, task 4). The sign.” This sensibility to design, which we can label proverbially as “ ” not all data are created equal, is illustrated schematically through COMPUTER SCIENCES a series of scenarios depicted in Fig. 1. Each design (shown in Fig. 1, This paper results from the Arthur M. Sackler Colloquium of the National Academy of Sciences, “Drawing Causal Inference from Big Data,” held March 26–27, 2015, at the Bottom) represents a triplet specifying the population, the regime National Academies of Sciences in Washington, DC. The complete program and video (observational vs. experimental), and the sampling method by which recordings of most presentations are available on the NAS website at www.nasonline.org/ each dataset is generated. This formal encoding allows us to de- Big-data. lineate the inferences that one can draw from each design to answer Author contributions: E.B. and J.P. wrote the paper. the query of interest (Fig. 1, Top). The authors declare no conflict of interest. Consider the task of predicting the distribution of outcomes Y This article is a PNAS Direct Submission. after intervening on a variable X, written Q = PðY = yjdoðX = xÞÞ. 1To whom correspondence should be addressed. Email: [email protected]. www.pnas.org/cgi/doi/10.1073/pnas.1510507113 PNAS | July 5, 2016 | vol. 113 | no. 27 | 7345–7352 information available in each of these tasks is characterized by a different syntactic form, representing a different design, and, nat- urally, each of these designs should lead to different inferences. What we shall see in subsequent sections of this paper is that the strategy of going from design to a query is the same across tasks; it follows simple rules of inference and decides, using syntactic ma- nipulations, whether the type of data available is sufficient for the task and, if so, how.* Empowered by this strategy, the central goal of this paper is to explicate the conditions under which causal effects can be estimated nonparametrically from multiple heterogeneous datasets. These conditions constitute the formal basis for many big data inferences because, in practice, data are never collected under idealized con- ditions, ready for use. The rest of this paper is organized as follows. We start by defining SCMs and stating the two fundamental laws of causal inference. We then consider respectively the problem of policy evaluation in observational and experimental settings, sam- pling selection bias, and data fusion from multiple populations. Fig. 1. Prototypical generalization tasks where the goal is, for example, to es- timate a causal effect in a target population (Top). Let V = fX, Y, Z, Wg.There The Structural Causal Model are different designs (Bottom) showing that data come from nonidealized con- ditions, specifically: (1) from the same population under an observational regime, At the center of the structural theory of causation lies a “structural ” PðvÞ;(2) from the same population under an experimental regime when Z is model, M, consisting of two sets of variables, U and V,andasetF randomized, PðvjdoðzÞÞ;(3) from the same population under sampling selection of functions that determine or simulate how values are assigned to bias, PðvjS = 1Þ or PðvjdoðxÞ, S = 1Þ;and(4) from a different population that is each variable Vi ∈ V. Thus, for example, the equation submitted to an experimental regime when X is randomized, PðvjdoðxÞ, S = sÞ, and observational studies in the target population. vi = fiðv, uÞ describes a physical process by which variable V is assigned the value i Eq. 1 implies that the distribution PðuÞ induces a well-defined v = f ðv, uÞ in response to the current values, v and u,ofthevariables i i probability on the counterfactual event Y = y, written PðY = yÞ, in V and U. Formally, the triplet hU, V, Fi defines a SCM, and the x x diagram that captures the relationships among the variables is called which is equal to the probability that a random unit u would † = the causal graph G (of M).
Load more

Recommended publications
  • The Application of Data Fusion Method in the Analysis of Ocean and Meteorology Observation Data
    International Journal of Hydrology Research Article Open Access The application of data fusion method in the analysis of ocean and meteorology observation data Abstract Volume 3 Issue 3 - 2019 Data fusion is a new technology of data processing for multi - source ocean meteorology 1 2 3 data. In order to clearly understand how to apply this technology in the data processing Wang Wei, Liu Zhi-jie, Zhao Yue, Gong 1 of ocean meteorology observation, the author first divides the fusion methods into three Xiao-qing categories, i.e., pixel-level fusion, feature-level fusion and decision-making level fusion. 1Tianjin Institute of Meteorological Science, China Then, the corresponding methods of each data fusion are discussed in detail. Afterward, the 2Meteorology Administrative of Xiqing District, China SST fusion data from China Meteorological administrative is analyzed in order to explain 3Meteorology Administrative of Jinnan District, China that the fusion data is applied in numerical forecast model on the China’s Bohai sea region. Finally, the authors believe that the data fusion technology of multi-source observation data Correspondence: Wang Wei, Tianjin Institute of has a good application value when the observation data is processed into grid data of ocean Meteorological Science, Tianjin, China, Tel 086-022-23358783, meteorology, which can be used as the grid truth-value of numerical model inspection. Email In addition, the fusion technology at decision-making level can also develop with the intelligent technology, and deeply mine the application of data fusion technology to the Received: May 13, 2019 | Published: June 03, 2019 ocean meteorology observation data. Keyword: data fusion, ocean meteorology, observation data, data processing Introduction evaluation tasks.
    [Show full text]
  • Causal Inference and Data Fusion in Econometrics∗
    TECHNICAL REPORT R-51 First version: Dec, 2019 Last revision: March, 2021 Causal Inference and Data Fusion in Econometrics∗ Paul Hunermund¨ Elias Bareinboim Copenhagen Business School Columbia University [email protected] [email protected] Learning about cause and effect is arguably the main goal in applied economet- rics. In practice, the validity of these causal inferences is contingent on a number of critical assumptions regarding the type of data that has been collected and the substantive knowledge that is available about the phenomenon under investiga- tion. For instance, unobserved confounding factors threaten the internal validity of estimates, data availability is often limited to non-random, selection-biased sam- ples, causal effects need to be learned from surrogate experiments with imperfect compliance, and causal knowledge has to be extrapolated across structurally hetero- geneous populations. A powerful causal inference framework is required in order to tackle all of these challenges, which plague essentially any data analysis to varying degrees. Building on the structural approach to causality introduced by Haavelmo (1943) and the graph-theoretic framework proposed by Pearl (1995), the artificial intelligence (AI) literature has developed a wide array of techniques for causal learn- ing that allow to leverage information from various imperfect, heterogeneous, and biased data sources (Bareinboim and Pearl, 2016). In this paper, we discuss recent advances made in this literature that have the potential to contribute to econo- metric methodology along three broad dimensions. First, they provide a unified and comprehensive framework for causal inference, in which the above-mentioned problems can be addressed in full generality.
    [Show full text]
  • Data Fusion – Resolving Data Conflicts for Integration
    Data Fusion – Resolving Data Conflicts for Integration Tutorial proposal, intended length 1.5 hours Xin (Luna) Dong Felix Naumann AT&T Labs Inc. Hasso Plattner Institute (HPI) Florham Park, NJ, USA Potsdam, Germany [email protected] [email protected] 1. MOTIVATION entity into a single record and resolving possible conflicts The amount of information produced in the world in- from different data sources. Data fusion plays an important creases by 30% every year and this rate will only go up. role in data integration systems: it detects and removes dirty With advanced network technology, more and more sour- data and increases correctness of the integrated data. ces are available either over the Internet or in enterprise Objectives and Coverage. The main objective of the pro- intranets. Modern data management applications, such as posed tutorial is to gather models, techniques, and systems setting up Web portals, managing enterprise data, managing of the wide but yet unconsolidated field of data fusion and community data, and sharing scientific data, often require present them in a concise and consolidated manner. In the integrating available data sources and providing a uniform 1.5-hour tutorial we will provide an overview of the causes interface for users to access data from different sources; such and challenges of data fusion. We will cover a wide set of requirements have been driving fruitful research on data in- both simple and advanced techniques to resolve data con- tegration over the last two decades [13, 15]. flicts in different types of settings and systems. Finally, we Data integration systems face two folds of challenges.
    [Show full text]
  • Data Mining and Fusion Techniques for Wsns As a Source of the Big Data Mohamed Mostafa Fouada,B,E,F, Nour E
    Available online at www.sciencedirect.com ScienceDirect Procedia Computer Science 65 ( 2015 ) 778 – 786 International Conference on Communication, Management and Information Technology (ICCMIT 2015) Data Mining and Fusion Techniques for WSNs as a Source of the Big Data Mohamed Mostafa Fouada,b,e,f, Nour E. Oweisb,e, Tarek Gaberb,c,e,f, Maamoun Ahmedd, Vaclav Snaselb aArab Academy for Science, Technology, and Maritime Transport, Cairo, EGYPT bFaculty of Electrical Engineering and Computer Science, VSB-Technical University of Ostrava, Ostrava - Czech Republic cFaculty of Computers and Informatics, Suez Canal University, Ismailia, Egypt dMiddle East University, Amman - Jordan eIT4Innovations, VSB-Technical University of Ostrava, Ostrava - Czech Republic fScientific Research Group in Egypt (SRGE), http://www.egyptscience.net Abstract The wide adoption of the Wireless Senor Networks (WSNs) applications around the world has increased the amount of the sensor data which contribute to the complexity of Big Data. This has emerged the need to the use of in-network data processing techniques which are very crucial for the success of the big data framework. This article gives overview and discussion about the state-of-the- art of the data mining and data fusion techniques designed for the WSNs. It discusses how these techniques can prepare the sensor data inside the network (in-network) before any further processing as big data. This is very important for both of the WSNs and the big data framework. For the WSNs, the in-network pre-processing techniques could lead to saving in their limited resources. For the big data side, receiving a clean, non-redundant and relevant data would reduce the excessive data volume, thus an overload reduction will be obtained at the big data processing platforms and the discovery of values from these data will be accelerated.
    [Show full text]
  • Data Fusion and Modeling for Construction Management Knowledge Discovery
    Data Fusion and Modeling for Construction Management Knowledge Discovery Lucio Soibelman *, Liang Y. Liu ** and Jianfeng Wu *** * Assistant Professor, Department of Civil and Environmental Engineering, University of Illinois at Urbana- Champaign, 205 N. Mathews Avenue, Urbana, IL 61801, U.S.A. [email protected] * Associate Professor, Department of Civil and Environmental Engineering, University of Illinois at Urbana- Champaign, 205 N. Mathews Avenue, Urbana, IL 61801, U.S.A. [email protected] * Research Assistant, Department of Civil and Environmental Engineering, University of Illinois at Urbana- Champaign, 205 N. Mathews Avenue, Urbana, IL 61801, U.S.A. [email protected] Abstract Advances in construction data analysis techniques have provided useful tools to discover explicit knowledge on historical databases supporting project managers’ decision making. However, in many situations, historical data are extracted and preprocessed for knowledge discovery based on time-consuming and problem-specific data preparation solutions, which often results in inefficiencies and inconsistencies. To overcome the problem, we are working on the development of a new data fusion methodology, which is designed to provide timely and consistent access to historical data for efficient and effective management knowledge discovery. The methodology is intended to be a new bridge between historical databases and data analysis techniques, which shields project managers from complex data preparation solutions, and enables them to use discovered knowledge for decision making more conveniently. This paper briefly describes the motivation, the background and the initial results of the ongoing research. 1. Introduction In today’s competitive market, the success of construction projects depends largely on project managers’ capabilities to make corrective decisions during construction planning and control stages.
    [Show full text]
  • Data Fusion by Matrix Factorization
    Note: Please refer to the extended version of this paper published in the IEEE Transactions on Pattern Analysis and Machine Intelligence (10.1109/TPAMI.2014.2343973). Data Fusion by Matrix Factorization Marinka Zitnikˇ [email protected] Faculty of Computer and Information Science, University of Ljubljana, Trˇzaˇska 25, SI-1000 Ljubljana, Slovenia BlaˇzZupan [email protected] Faculty of Computer and Information Science, University of Ljubljana, Trˇzaˇska 25, SI-1000 Ljubljana, Slovenia Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX-77030, USA Abstract our in the study of disease. Let us say that we ex- For most problems in science and engineer- amine susceptibility to a particular disease and have ing we can obtain data that describe the access to the patients’ clinical data together with data system from various perspectives and record on their demographics, habits, living environments, the behaviour of its individual components. friends, relatives, and movie-watching habits and genre Heterogeneous data sources can be collec- ontology. Mining such a diverse data collection may tively mined by data fusion. Fusion can fo- reveal interesting patterns that would remain hidden if cus on a specific target relation and exploit considered only directly related, clinical data. What if directly associated data together with data the disease was less common in living areas with more on the context or additional constraints. In open spaces or in environments where people need to the paper we describe a data fusion approach walk instead of drive to the nearest grocery? Is the with penalized matrix tri-factorization that disease less common among those that watch come- simultaneously factorizes data matrices to dies and ignore politics and news? reveal hidden associations.
    [Show full text]
  • An Overview of Iot Sensor Data Processing, Fusion, and Analysis Techniques
    sensors Review An Overview of IoT Sensor Data Processing, Fusion, and Analysis Techniques Rajalakshmi Krishnamurthi 1, Adarsh Kumar 2 , Dhanalekshmi Gopinathan 1, Anand Nayyar 3,4,* and Basit Qureshi 5 1 Department of Computer Science and Engineering, Jaypee Institute of Information Technology, Noida 201309, India; [email protected] (R.K.); [email protected] (D.G.) 2 School of Computer Science, University of Petroleum and Energy Studies, Dehradun 248007, India; [email protected] 3 Graduate School, Duy Tan University, Da Nang 550000, Vietnam 4 Faculty of Information Technology, Duy Tan University, Da Nang 550000, Vietnam 5 Department of Computer Science, Prince Sultan University, Riyadh 11586, Saudi Arabia; [email protected] * Correspondence: [email protected] Received: 21 August 2020; Accepted: 22 October 2020; Published: 26 October 2020 Abstract: In the recent era of the Internet of Things, the dominant role of sensors and the Internet provides a solution to a wide variety of real-life problems. Such applications include smart city, smart healthcare systems, smart building, smart transport and smart environment. However, the real-time IoT sensor data include several challenges, such as a deluge of unclean sensor data and a high resource-consumption cost. As such, this paper addresses how to process IoT sensor data, fusion with other data sources, and analyses to produce knowledgeable insight into hidden data patterns for rapid decision-making. This paper addresses the data processing techniques such as data denoising, data outlier detection, missing data imputation and data aggregation. Further, it elaborates on the necessity of data fusion and various data fusion methods such as direct fusion, associated feature extraction, and identity declaration data fusion.
    [Show full text]
  • Information Acquisition in Data Fusion Systems
    Information Acquisition in Data Fusion Systems Ronnie Johansson TRITA-NA-0328 Licentiate Thesis Royal Institute of Technology Department of Numerical Analysis and Computer Science Akademisk avhandling som med tillstånd av Kungl Tekniska Högskolan framlägges till offentlig granskning för avläggande av teknologie licentiatexamen torsdagen den 18 december 2003kl. 14.00 i Kollegiesalen, Administrationsbyggnaden, Kungliga Tekniska Högskolan, Valhallavägen 79, Stockholm.. TRITA-NA-0328 ISSN 0348-2952 ISRN KTH/NA/R--03/28--SE ISBN 91-7283-655-5 CVAP283 © Ronnie Johansson, november 2003 Universitetsservice US AB, Stockholm 2003 Abstract By purposefully utilising sensors, for instance by a data fusion system, the state of some system-relevant environment might be adequately assessed to support decision-making. The ever increasing access to sensors offers great opportunities, but also incurs grave challenges. As a result of managing multiple sensors one can, e.g., expect to achieve a more comprehensive, resolved, certain and more frequently updated assessment of the environment than would be possible otherwise. Chal- lenges include data association, treatment of conflicting information and strategies for sensor coordination. We use the term information acquisition to denote the skill of a data fusion sys- tem to actively acquire information. The aim of this thesis is to instructively situate that skill in a general context, explore and classify related research, and highlight key issues and possible future work. It is our hope that this thesis will facilitate communication, understanding and future efforts for information acquisition. The previously mentioned trend towards utilisation of large sets of sensors makes us especially interested in large-scale information acquisition, i.e., acquisition using many and possibly spatially distributed and heterogeneous sensors.
    [Show full text]
  • CS 520 Data Integration, Warehousing, and Provenance
    CS 520 Data Integration, Warehousing, and Provenance Course Description: This course introduces the basic concepts of data integration, data warehousing, and provenance. We will learn how to resolve structural heterogeneity through schema matching and mapping. The course introduces techniques for querying several heterogeneous datasources at once (data integration) and translating data between databases with different data representa- tions (data exchange). Furthermore, we will cover the data-warehouse paradigm including the Extract-Transform-Load (ETL) process, the data cube model and its relational representa- tions (such as snowflake and star schema), and efficient processing of analytical queries. This will be contrasted with Big Data analytics approaches that (besides other differences) significantly reduce the upfront cost of analytics. When feeding data through complex processing pipelines such as data exchange transformations or ETL workflows, it is easy to loose track of the origin of data. In the last part of the course we therefore cover techniques for representing and keeping track of the origin and creation process of data - aka its provenance. The course is emphasizing practical skills through a series of homework assignments that help students develop a strong background in data integration systems and techniques. At the same time, it also addresses the underlying formalisms. For example, we will discuss the logic based languages used for schema mapping and the dimensional data model as well as their practical application (e.g., developing an ETL workflow with rapid miner and creating a mapping between two example schemata). The literature reviews will familiarize students with data integration and provenance research. Course Material: The following text book will be helpful for following the course and studying the presented material.
    [Show full text]
  • Cheminformatics and the Semantic Web: Adding Value with Linked Data and Enhanced Provenance
    Advanced Review Cheminformatics and the Semantic Web: adding value with linked data and enhanced provenance Jeremy G. Frey∗ and Colin L. Bird Cheminformatics is evolving from being a field of study associated primarily with drug discovery into a discipline that embraces the distribution, management, ac- cess, and sharing of chemical data. The relationship with the related subject of bioinformatics is becoming stronger and better defined, owing to the influence of Semantic Web technologies, which enable researchers to integrate hetero- geneous sources of chemical, biochemical, biological, and medical information. These developments depend on a range of factors: the principles of chemical identifiers and their role in relationships between chemical and biological enti- ties; the importance of preserving provenance and properly curated metadata; and an understanding of the contribution that the Semantic Web can make at all stages of the research lifecycle. The movements toward open access, open source, and open collaboration all contribute to progress toward the goals of integration. C " 2013 John Wiley & Sons, Ltd. How to cite this article: WIREs Comput Mol Sci 2013. doi: 10.1002/wcms.1127 INTRODUCTION cipline of bioinformatics evolved more recently, in heminformatics is usually defined in terms of response to the vast amount of data generated by the application of computer science and infor- molecular biology, applying mathematical, and com- mationC technology to problems in the chemical sci- putational techniques not only to the management ences. Brown1 introduced the term chemoinformatics of that data but also to understanding the biological in 1998, in the context of drug discovery, although processes, pathways, and interactions involved.
    [Show full text]
  • Information Quality Assessment for Data Fusion Systems
    data Article Information Quality Assessment for Data Fusion Systems Miguel A. Becerra 1,2,*,† , Catalina Tobón 2,† and Andrés Eduardo Castro-Ospina 1,† and Diego H. Peluffo-Ordóñez 3,4 1 Instituto Tecnológico Metropolitano, Cra. 74d #732, Medellín 050034, Colombia; [email protected] 2 Facultad de Ciencias Básicas, Universidad de Medellín, MATBIOM, Cra. 87 #30-65, Medellín 050010, Colombia; [email protected] 3 Modeling, Simulation and Data Analysis (MSDA) Research Program, Mohammed VI Polytechnic University, Ben Guerir 47963, Morocco; [email protected] or [email protected] 4 Faculty of Engineering, Corporación Universitaria Autónoma de Nariño, Carrera 28 No. 19-24, Pasto 520001, Colombia * Correspondence: [email protected] † These authors contributed equally to this work. Abstract: This paper provides a comprehensive description of the current literature on data fusion, with an emphasis on Information Quality (IQ) and performance evaluation. This literature review highlights recent studies that reveal existing gaps, the need to find a synergy between data fusion and IQ, several research issues, and the challenges and pitfalls in this field. First, the main models, frameworks, architectures, algorithms, solutions, problems, and requirements are analyzed. Second, a general data fusion engineering process is presented to show how complex it is to design a framework for a specific application. Third, an IQ approach , as well as the different methodologies and frameworks used to assess IQ in information systems are addressed; in addition, data fusion systems are presented along with their related criteria. Furthermore, information on the context in data fusion systems and its IQ assessment are discussed. Subsequently, the issue of data fusion Citation: Becerra, M.A.; Tobón, C.; systems’ performance is reviewed.
    [Show full text]
  • The Use of Data Fusion on Multiple Substructural Analysis Based GA Runs
    J. Appl. Environ. Biol. Sci. , 7(2S)30-36, 2017 ISSN: 2090 -4274 Journal of Applied Environmental © 2017, TextRoad Publication and Biological Sciences www.textroad.com The Use of Data Fusion on Multiple Substructural Analysis Based GA Runs Nor Samsiah Sani Faculty of Information Science and Technology, National University of Malaysia, Bangi, Selangor, Malaysia Received: February 21, 2017 Accepted: April30,2017 ABSTRACT Substructural analysis (SSA) was one of the very first machine learning techniques to be applied to chemoinformatics in the area of virtual screening. Recently, the use of SSA method based on genetic traits particularly the genetic algorithm (GA) was shown to be superior to the SSA based on a naive Bayesian classifier, both in terms of active compound retrieval rate and predictive performance. Extensive studies on data fusion have been carried out on similarity-based rankings, but there are limited findings on the fusion of data obtained from evolutionary algorithm techniques in chemoinformatics. This paper explores the feasibility of data fusion on the GA-based SSA. Data fusion is a method to produce a final ranking list from multiple sets of ranking lists via several fusion rules. Based on the encouraging results obtained using the GA, the application of data fusion to the GA-based SSA weighting schemes are examined in this paper in order to enhance retrieval performance of 2D-based fingerprint predictive method. Our experiments used the MDDR and WOMBAT datasets. The results show that data fusion can indeed enhance retrieval performance of evolutionary techniques further in the case of evolutionary algorithm techniques, and specifically the GA- based SSA.
    [Show full text]