6 research outputs found
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Hunting High and Low: Visualising Shifting Correlations in Financial Markets
The analysis of financial assets' correlations is fundamental to many aspects of finance theory and practice, especially modern portfolio theory and the study of risk. In order to manage investment risk, in-depth analysis of changing correlations is needed, with both high and low correlations between financial assets (and groups thereof) important to identify. In this paper, we propose a visual analytics framework for the interactive analysis of relations and structures in dynamic, high-dimensional correlation data. We conduct a series of interviews and review the financial correlation analysis literature to guide our design. Our solution combines concepts from multi-dimensional scaling, weighted complete graphs and threshold networks to present interactive, animated displays which use proximity as a visual metaphor for correlation and animation stability to encode correlation stability. We devise interaction techniques coupled with context-sensitive auxiliary views to support the analysis of subsets of correlation networks. As part of our contribution, we also present behaviour profiles to help guide future users of our approach. We evaluate our approach by checking the validity of the layouts produced, presenting a number of analysis stories, and through a user study. We observe that our solutions help unravel complex behaviours and resonate well with study participants in addressing their needs in the context of correlation analysis in finance
ICE: An Interactive Configuration Explorer for High Dimensional Categorical Parameter Spaces
There are many applications where users seek to explore the impact of the
settings of several categorical variables with respect to one dependent
numerical variable. For example, a computer systems analyst might want to study
how the type of file system or storage device affects system performance. A
usual choice is the method of Parallel Sets designed to visualize multivariate
categorical variables. However, we found that the magnitude of the parameter
impacts on the numerical variable cannot be easily observed here. We also
attempted a dimension reduction approach based on Multiple Correspondence
Analysis but found that the SVD-generated 2D layout resulted in a loss of
information. We hence propose a novel approach, the Interactive Configuration
Explorer (ICE), which directly addresses the need of analysts to learn how the
dependent numerical variable is affected by the parameter settings given
multiple optimization objectives. No information is lost as ICE shows the
complete distribution and statistics of the dependent variable in context with
each categorical variable. Analysts can interactively filter the variables to
optimize for certain goals such as achieving a system with maximum performance,
low variance, etc. Our system was developed in tight collaboration with a group
of systems performance researchers and its final effectiveness was evaluated
with expert interviews, a comparative user study, and two case studies.Comment: 10 pages, Published by IEEE at VIS 2019 (Vancouver, BC, Canada
Visual Analytics Methodologies on Causality Analysis
abstract: Causality analysis is the process of identifying cause-effect relationships among variables. This process is challenging because causal relationships cannot be tested solely based on statistical indicators as additional information is always needed to reduce the ambiguity caused by factors beyond those covered by the statistical test. Traditionally, controlled experiments are carried out to identify causal relationships, but recently there is a growing interest in causality analysis with observational data due to the increasing availability of data and tools. This type of analysis will often involve automatic algorithms that extract causal relations from large amounts of data and rely on expert judgment to scrutinize and verify the relations. Over-reliance on these automatic algorithms is dangerous because models trained on observational data are susceptible to bias that can be difficult to spot even with expert oversight. Visualization has proven to be effective at bridging the gap between human experts and statistical models by enabling an interactive exploration and manipulation of the data and models. This thesis develops a visual analytics framework to support the interaction between human experts and automatic models in causality analysis. Three case studies were conducted to demonstrate the application of the visual analytics framework in which feature engineering, insight generation, correlation analysis, and causality inspections were showcased.Dissertation/ThesisDoctoral Dissertation Computer Science 201