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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Immersive Space to Think: Immersive Analytics for Sensemaking with Non-Quantitative Datasets

Lisle, Lorance Richard 09 February 2023 (has links)
Analysts often work with large complex non-quantitative datasets in order to better understand concepts, themes, and other forms of insight contained within them. As defined by Pirolli and Card, this act of sensemaking is cognitively difficult, and is performed iteratively and repetitively through various stages of understanding. Immersive analytics has purported to assist with this process through putting users in virtual environments that allows them to sift through and explore data in three-dimensional interactive settings. Most previous research, however, has focused on quantitative data, where users are interacting with mostly numerical representations of data. We designed Immersive Space to Think, an immersive analytics approach to assist users perform the act of sensemaking with non-quantitative datasets, affording analysts the ability to manipulate data artifacts, annotate them, search through them, and present their findings. We performed several studies to understand and refine our approach and how it affects users sensemaking strategies. An exploratory virtual reality study found that users place documents in 2.5-dimensional structures, where we saw semicircular, environmental, and planar layouts. The environmental layout, in particular, used features of the environment as scaffolding for users' sensemaking process. In a study comparing levels of mixed reality as defined by Milgram-Kishino's Reality-Virtuality Continuum, we found that an augmented virtuality solution best fits users' preferences while still supporting external tools. Lastly, we explored how users deal with varying amounts of space and three-dimensional user interaction techniques in a comparative study comparing small virtual monitors, large virtual monitors, and a seated-version implementation of Immersive Space to Think. Our participants found IST best supported the task of sensemaking, with evidence that users leveraged spatial memory and utilized depth to denote additional meaning in the immersive condition. Overall, Immersive Space to Think affords an effective sensemaking three-dimensional space using 3D user interaction techniques that can leverage embodied cognition and spatial memory which aids the users understanding. / Doctor of Philosophy / Humans are constantly trying to make sense of the world around them. Whether they're a detective trying to understand what happened at a crime scene or a shopper trying to find the best office chair, people are consuming vast quantities of data to assist them with their choices. This process can be difficult, and people are often returning to various pieces of data repeatedly to remember why they are making the choice they decided upon. With the advent of cheap virtual reality products, researchers have pursued the technology as a way for people to better understand large sets of data. However, most mixed reality applications looking into this problem focus on numerical data, whereas a lot of the data people process is multimedia or text-based in nature. We designed and developed a mixed reality approach for analyzing this type of data called Immersive Space to Think. Our approach allows users to look at and move various documents around in a virtual environment, take notes or highlight those documents, search those documents, and create reports that summarize what they've learned. We also performed several studies to investigate and evolve our design. First, we ran a study in virtual reality to understand how users interact with documents using Immersive Space to Think. We found users arranging documents around themselves in a semicircular or flat plane pattern, or using various cues in the virtual environment as a way to organize the document set. Furthermore, we performed a study to understand user preferences with augmented and virtual reality. We found a mix of the two, also known as augmented virtuality, would best support user preferences and ability. Lastly, we ran two comparative studies to understand how three dimensional space and interaction affects user strategies. We ran a small user study looking at how a single student uses a desktop computer with a single display as well as immersive space to think to write essays. We found that they wrote essays with a better understanding of the source data with Immersive Space to Think than the desktop setup. We conducted a larger study where we compared a small virtual monitor simulating a traditional desktop screen, a large virtual monitor simulating a monitor 8 times the size of traditional desktop monitors, and immersive space to think. We found participants engaged with documents more in Immersive Space to Think, and used the space to denote importance for documents. Overall, Immersive Space to Think provides a compelling environment that assists users in understanding sets of documents.
112

Narrative Maps: A Computational Model to Support Analysts in Narrative Sensemaking

Keith Norambuena, Brian Felipe 08 August 2023 (has links)
Narratives are fundamental to our understanding of the world, and they are pervasive in all activities that involve representing events in time. Narrative analysis has a series of applications in computational journalism, intelligence analysis, and misinformation modeling. In particular, narratives are a key element of the sensemaking process of analysts. In this work, we propose a narrative model and visualization method to aid analysts with this process. In particular, we propose the narrative maps framework—an event-based representation that uses a directed acyclic graph to represent the narrative structure—and a series of empirically defined design guidelines for map construction obtained from a user study. Furthermore, our narrative extraction pipeline is based on maximizing coherence—modeled as a function of surface text similarity and topical similarity—subject to coverage—modeled through topical clusters—and structural constraints through the use of linear programming optimization. For the purposes of our evaluation, we focus on the news narrative domain and showcase the capabilities of our model through several case studies and user evaluations. Moreover, we augment the narrative maps framework with interactive AI techniques—using semantic interaction and explainable AI—to create an interactive narrative model that is capable of learning from user interactions to customize the narrative model based on the user's needs and providing explanations for each core component of the narrative model. Throughout this process, we propose a general framework for interactive AI that can handle similar models to narrative maps—that is, models that mix continuous low-level representations (e.g., dimensionality reduction) with more abstract high-level discrete structures (e.g., graphs). Finally, we evaluate our proposed framework through an insight-based user study. In particular, we perform a quantitative and qualitative assessment of the behavior of users and explore their cognitive strategies, including how they use the explainable AI and semantic interaction capabilities of our system. Our evaluation shows that our proposed interactive AI framework for narrative maps is capable of aiding users in finding more insights from data when compared to the baseline. / Doctor of Philosophy / Narratives are essential to how we understand the world. They help us make sense of events that happen over time. This research focuses on developing a method to assist people, like journalists and analysts, in understanding complex information. To do this, we introduce a new approach called narrative maps. This model allows us to extract and visualize stories from text data. To improve our model, we use interactive artificial intelligence techniques. These techniques allow our model to learn from user feedback and be customized to fit different needs. We also use these methods to explain how the model works, so users can understand it better. We evaluate our approach by studying how users interact with it when doing a task with news stories. We consider how useful the system is in helping users gain insights. Our results show that our method aids users in finding important insights compared to traditional methods.
113

Comparison of Computational Notebook Platforms for Interactive Visual Analytics: Case Study of Andromeda Implementations

Liu, Han 22 September 2022 (has links)
Existing notebook platforms have different capabilities for supporting visual analytics use. It is not clear which platform to choose for implementing visual analytics notebooks. In this work, we investigated the problem using Andromeda, an interactive dimension reduction algorithm, and implemented it using three different notebook platforms: 1) Python-based Jupyter Notebook, 2) JavaScript-based Observable Notebook, and 3) Jupyter Notebook embedding both Python (data science use) and JavaScript (visual analytics use). We also made comparisons for all the notebook platforms via a case study based on metrics such as programming difficulty, notebook organization, interactive performance, and UI design choice. Furthermore, guidelines are provided for data scientists to choose one notebook platform for implementing their visual analytics notebooks in various situations. Laying the groundwork for future developers, advice is also given on architecting better notebook platforms. / Master of Science / Data scientists are interested in developing visual analytics notebooks. However, different notebook platforms have different support for visual analytics components, such as visualizations and user interactions. To investigate which notebook platform to use for visual analytics, we built notebooks based on three different notebook platforms, i.e., Jupyter Notebook (with Python), Observable Notebook (with JavaScript), and Jupyter Notebook (with Python and JavaScript). Based on the implementation and user interactions, we explained why significant differences exist via specific metrics, such as programming difficulty, notebook organization, interactive performance, and the UI design choice. Furthermore, our work will benefit future researchers in choosing suitable notebook platforms for implementing visual analytics notebooks.
114

Big data, data mining, and machine learning: value creation for business leaders and practitioners

Dean, J. January 2014 (has links)
No / Big data is big business. But having the data and the computational power to process it isn't nearly enough to produce meaningful results. Big Data, Data Mining, and Machine Learning: Value Creation for Business Leaders and Practitioners is a complete resource for technology and marketing executives looking to cut through the hype and produce real results that hit the bottom line. Providing an engaging, thorough overview of the current state of big data analytics and the growing trend toward high performance computing architectures, the book is a detail-driven look into how big data analytics can be leveraged to foster positive change and drive efficiency. With continued exponential growth in data and ever more competitive markets, businesses must adapt quickly to gain every competitive advantage available. Big data analytics can serve as the linchpin for initiatives that drive business, but only if the underlying technology and analysis is fully understood and appreciated by engaged stakeholders.
115

What does Big Data has in-store for organisations: An Executive Management Perspective

Hussain, Zahid I., Asad, M., Alketbi, R. January 2017 (has links)
No / With a cornucopia of literature on Big Data and Data Analytics it has become a recent buzzword. The literature is full of hymns of praise for big data, and its potential applications. However, some of the latest published material exposes the challenges involved in implementing Big Data (BD) approach, where the uncertainty surrounding its applications is rendering it ineffective. The paper looks at the mind-sets and perspective of executives and their plans for using Big Data for decision making. Our data collection involved interviewing senior executives from a number of world class organisations in order to determine their understanding of big data, its limitations and applications. By using the information gathered by this is used to analyse how well executives understand big data and how well organisations are ready to use it effectively for decision making. The aim is to provide a realistic outlook on the usefulness of this technology and help organisations to make suitable and realistic decisions on its investment. Professionals and academics are becoming increasingly interested in the field of big data (BD) and data analytics. Companies invest heavily into acquiring data, and analysing it. More recently the focus has switched towards data available through the internet which appears to have brought about new data collection opportunities. As the smartphone market developed further, data sources extended to include those from mobile and sensor networks. Consequently, organisations started using the data and analysing it. Thus, the field of business intelligence emerged, which deals with gathering data, and analysing it to gain insights and use them to make decisions (Chen, et al., 2012). BD is seem to have a huge immense potential to provide powerful information businesses. Accenture claims (2015) that organisations are extremely satisfied with their BD projects concerned with enhancing their customer reach. Davenport (2006) has presented applications in which companies are using the power of data analytics to consistently predict behaviours and develop applications that enable them to unearth important yet difficult to see customer preferences, and evolve rapidly to generate revenues.
116

E-Learning Symposium 2012 : aktuelle Anwendungen, innovative Prozesse und neueste Ergebnisse aus der E-Learning-Praxis ; Potsdam, 17. November 2012

January 2013 (has links)
Dieser Tagungsband beinhaltet die auf dem E-Learning Symposium 2012 an der Universität Potsdam vorgestellten Beiträge zu aktuellen Anwendungen, innovativen Prozesse und neuesten Ergebnissen im Themenbereich E-Learning. Lehrende, E-Learning-Praktiker und -Entscheider tauschten ihr Wissen über etablierte und geplante Konzepte im Zusammenhang mit dem Student-Life-Cycle aus. Der Schwerpunkt lag hierbei auf der unmittelbaren Unterstützung von Lehr- und Lernprozessen, auf Präsentation, Aktivierung und Kooperation durch Verwendung von neuen und etablierten Technologien.
117

Orientação para marketing analytics: antecedentes e impacto no desempenho do negócio. / Marketing analytics orientation: antecedents and impact on business performance

Bedante, Gabriel Navarro 11 March 2019 (has links)
Com a evolução tecnológica pela qual o mundo vem passando nos últimos anos, o tema Marketing Analytics vem ganhando relevância gerencial e acadêmica. No entanto, pouco se avançou no entendimento do que determina a inclinação de uma empresa a adotar a prática de Analytics para tomada de decisão nas atividades de Marketing, ou seja, sua Orientação para Marketing Analytics (OMA). Além disso, pouco se sabe sobre os impactos dessa orientação nos resultados da empresa. Para suprir essas lacunas, essa pesquisa buscou entender quais os construtos antecedentes que poderiam influenciar a Orientação para Marketing Analytics, bem como se essa orientação levaria a um melhor desempenho do negócio. Para tanto, por meio de uma vasta revisão da literatura, delimitou-se o escopo de Orientação para Marketing Analytics, apresentando uma definição para o construto, um modelo teórico e proposições de pesquisa. Na etapa seguinte, foram feitas entrevistas em profundidade com especialistas em Analytics e executivos de marketing para aprofundar o conceito de Orientação para Marketing Analytics e para entender quais os determinantes para uma empresa ser orientada para Marketing Analytics. A terceira e última parte desse trabalho se focou em desenvolver um modelo de mensuração para Orientação para Marketing Analytics e testar o modelo estrutural proposto junto a uma amostra de 127 profissionais de marketing e especialistas em Analytics. As respostas foram analisadas por meio de Modelagem de Equações Estruturais (PLS-SEM) e os resultados indicaram que o suporte da alta administração desempenha um papel relevante na valorização de habilidades analíticas das pessoas, nos investimentos em infraestrutura tecnológica e na orientação para processos da empresa. Além disso, observou-se que todos esses antecedentes apresentam influência significativa na Orientação para Marketing Analytics da empresa que, por sua vez, tem impacto positivo no desempenho percebido do negócio. / With the technological evolution that the world has been going through in recent years, the topic Marketing Analytics has gained managerial and academic relevance. However, little progress has been made in understanding what determines a company\'s willingness to adopt the practice of Analytics for decision-making in Marketing activities, ie its Marketing Analytics Orientation (MAO). In addition, little is known about the impacts of this orientation on company results. To fill these gaps, this research sought to understand which antecedent could influence the Marketing Analytics Orientation, as well as whether such orientation would lead to better business performance. To do so, through a vast literature review, the scope of Marketing Analytics Orientation was delimited, presenting a definition for the construct, a theoretical model and research propositions. In the next step, in-depth interviews were conducted with analytics experts and marketing executives to deepen the concept of Marketing Analytics Orientation and to understand the determinants for a company to be Marketing Analytics-oriented. The third and final part of this work focused on developing a measurement model for Marketing Analytics Orientation and testing the proposed structural model with a sample of 127 marketing professionals and Analytics experts. The responses were analyzed through Structural Equation Modeling (PLS-SEM) and the results indicated that the top management support plays a relevant role in the appreciation of people\'s analytical skills, on investments in technological infrastructure and in the company\'s processes orientation. The result of this work showed that all of these antecedents had significant influence on the company\'s Marketing Analytics Orientation, which in turn had a positive impact on the perceived performance of the business.
118

Rättidiga beslut genererade från olika typer av dataanalyser : En fallstudie inom Landstinget i Värmland / Right-time Decisions Generated from Different types of Data Analysis : A Case Study Within the County Council of Värmland

Molin, Mattias January 2019 (has links)
Syftet med denna kandidatuppsats är att, via kvalitativa intervjuer, identifiera och beskriva ett landstings process för hur patient- och sjukvårdsdata, genom olika typer av dataanalyser, kan generera rättidiga beslut.   I det valda kvalitativa tillvägagångssättet skapades en semi-strukturerad intervjuguide, baserad på en analysmodell. Fem intervjuer med anställda inom fallstudieorganisationen genomfördes. För att underlätta för respondenterna och ge en tydlig helhetssyn på intervjuns innehåll, fick respondenterna innan intervjun se analysmodellen som skapats.   Deskriptiv analys är den vanligaste dataanalysmodellen som används av respondenterna, i form av verksamhets- och produktionsuppföljning. Det framgår även i undersökningen att det är viktigt med ett brett dataunderlag för beslutsfattning och att Landstinget i Värmland överlag är en mycket faktabaserad organisation. Förutsättningarna för att kunna fatta rättidiga beslut, genererade från dataanalyser, anses vara att veta vilka frågeställningar som ska besvaras, att data snabbt finns tillgänglig och att analyser utförs på denna tillgängliga data. Men även om data snabbt finns tillgängligt för beslutsfattarna och analyser gjorts, medför inte det rättidiga beslut. Data ger inte alltid en korrekt eller sann bild, utan behöver först tolkas innan besluten kan fattas. Tolkningar av data kan skilja sig åt vilket medför att ytterligare en person behöver titta på materialet, vilket också medför att besluten skjuts fram. Det anses även saknas ett enhetligt arbetssätt för hur de anställda arbetar i vårdsystemen.   Rättidiga beslut finns på olika nivåer inom landstinget. När det gäller den övergripande nivån är det inte brådskande med beslut, men ju mer operativt personalen arbetar desto viktigare är det med snabba beslut. Detta visar att ”rättidiga beslut” har olika betydelser, beroende på var i verksamheten de anställda befinner sig. Vården är tidspressad och det är inte alltid det finns möjlighet att analysera de data som finns tillräckligt mycket.
119

Centralized and distributed learning methods for predictive health analytics

Brisimi, Theodora 02 November 2017 (has links)
The U.S. health care system is considered costly and highly inefficient, devoting substantial resources to the treatment of acute conditions in a hospital setting rather than focusing on prevention and keeping patients out of the hospital. The potential for cost savings is large; in the U.S. more than $30 billion are spent each year on hospitalizations deemed preventable, 31% of which is attributed to heart diseases and 20% to diabetes. Motivated by this, our work focuses on developing centralized and distributed learning methods to predict future heart- or diabetes- related hospitalizations based on patient Electronic Health Records (EHRs). We explore a variety of supervised classification methods and we present a novel likelihood ratio based method (K-LRT) that predicts hospitalizations and offers interpretability by identifying the K most significant features that lead to a positive prediction for each patient. Next, assuming that the positive class consists of multiple clusters (hospitalized patients due to different reasons), while the negative class is drawn from a single cluster (non-hospitalized patients healthy in every aspect), we present an alternating optimization approach, which jointly discovers the clusters in the positive class and optimizes the classifiers that separate each positive cluster from the negative samples. We establish the convergence of the method and characterize its VC dimension. Last, we develop a decentralized cluster Primal-Dual Splitting (cPDS) method for large-scale problems, that is computationally efficient and privacy-aware. Such a distributed learning scheme is relevant for multi-institutional collaborations or peer-to-peer applications, allowing the agents to collaborate, while keeping every participant's data private. cPDS is proved to have an improved convergence rate compared to existing centralized and decentralized methods. We test all methods on real EHR data from the Boston Medical Center and compare results in terms of prediction accuracy and interpretability.
120

A visual analytics approach for passing strateggies analysis in soccer using geometric features

Malqui, José Luis Sotomayor January 2017 (has links)
As estrategias de passes têm sido sempre de interesse para a pesquisa de futebol. Desde os inícios do futebol, os técnicos tem usado olheiros, gravações de vídeo, exercícios de treinamento e feeds de dados para coletar informações sobre as táticas e desempenho dos jogadores. No entanto, a natureza dinâmica das estratégias de passes são bastante complexas para refletir o que está acontecendo dentro do campo e torna difícil o entendimento do jogo. Além disso, existe uma demanda crecente pela deteção de padrões e analise de estrategias de passes popularizado pelo tiki-taka utilizado pelo FC. Barcelona. Neste trabalho, propomos uma abordagem para abstrair as sequências de pases e agrupálas baseadas na geometria da trajetória da bola. Para analizar as estratégias de passes, apresentamos um esquema de visualização interátiva para explorar a frequência de uso, a localização espacial e ocorrência temporal das sequências. A visualização Frequency Stripes fornece uma visão geral da frequencia dos grupos achados em tres regiões do campo: defesa, meio e ataque. O heatmap de trajetórias coordenado com a timeline de passes permite a exploração das formas mais recorrentes no espaço e tempo. Os resultados demostram oito trajetórias comunes da bola para sequências de três pases as quais dependem da posição dos jogadores e os ângulos de passe. Demonstramos o potencial da nossa abordagem com utilizando dados de várias partidas do Campeonato Brasileiro sob diferentes casos de estudo, e reportamos os comentários de especialistas em futebol. / Passing strategies analysis has always been of interest for soccer research. Since the beginning of soccer, managers have used scouting, video footage, training drills and data feeds to collect information about tactics and player performance. However, the dynamic nature of passing strategies is complex enough to reflect what is happening in the game and makes it hard to understand its dynamics. Furthermore, there exists a growing demand for pattern detection and passing sequence analysis popularized by FC Barcelona’s tiki-taka. We propose an approach to abstract passing strategies and group them based on the geometry of the ball trajectory. To analyse passing sequences, we introduce a interactive visualization scheme to explore the frequency of usage, spatial location and time occurrence of the sequences. The frequency stripes visualization provide, an overview of passing groups frequency on three pitch regions: defense, middle, attack. A trajectory heatmap coordinated with a passing timeline allow, for the exploration of most recurrent passing shapes in temporal and spatial domains. Results show eight common ball trajectories for three-long passing sequences which depend on players positioning and on the angle of the pass. We demonstrate the potential of our approach with data from the Brazilian league under several case studies, and report feedback from a soccer expert.

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