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Scatterplot layout for high-dimensional data visualization

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Abstract

Multi-dimensional data visualization is an important research topic that has been receiving increasing attention. Several techniques that apply scatterplot matrices have been proposed to represent multi-dimensional data as a collection of two-dimensional data visualization spaces. Typically, when using the scatterplot-based approach it is easier to understand relations between particular pairs of dimensions, but it often requires too large display spaces to display all possible scatterplots. This paper presents a technique to display meaningful sets of scatterplots generated from high-dimensional datasets. Our technique first evaluates all possible scatterplots generated from high-dimensional datasets, and selects meaningful sets. It then calculates the similarity between arbitrary pairs of the selected scatterplots, and places relevant scatterplots closer together in the display space while they never overlap each other. This design policy makes users easier to visually compare relevant sets of scatterplots. This paper presents algorithms to place the scatterplots by the combination of ideal position calculation and rectangle packing algorithms, and two examples demonstrating the effectiveness of the presented technique. Graphical Abstract

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... In addition, it can be difficult for humans to visually compare arbitrary pairs of SPs that are distantly placed in the display space. Several studies aimed at selecting meaningful sets of SPs and effectively arrange them onto the display spaces [6] [30] [36] [38] [42]; however, these studies often had difficulty to visually compare large number of SPs. ...
... Suematsu et al. [33] also converted high-dimensional datasets into low-dimensional subsets and visualized these subsets using multiple PCPs arranged on display spaces based upon their similarity and correlation. Using similar ideas, Zheng et al. [42] selected SPs based upon the meaningfulness of the dimensions being displayed and adjusted their layout based upon their similarity. Claessen et al. [5] presented a technique to visualize high-dimensional datasets by selecting sets of low-dimensional subspaces and representing them as a combination of PCPs and SPs. ...
Preprint
Parallel coordinate plots (PCPs) are among the most useful techniques for the visualization and exploration of high-dimensional data spaces. They are especially useful for the representation of correlations among the dimensions, which identify relationships and interdependencies between variables. However, within these high-dimensional spaces, PCPs face difficulties in displaying the correlation between combinations of dimensions and generally require additional display space as the number of dimensions increases. In this paper, we present a new technique for high-dimensional data visualization in which a set of low-dimensional PCPs are interactively constructed by sampling user-selected subsets of the high-dimensional data space. In our technique, we first construct a graph visualization of sets of well-correlated dimensions. Users observe this graph and are able to interactively select the dimensions by sampling from its cliques, thereby dynamically specifying the most relevant lower dimensional data to be used for the construction of focused PCPs. Our interactive sampling overcomes the shortcomings of the PCPs by enabling the visualization of the most meaningful dimensions (i.e., the most relevant information) from high-dimensional spaces. We demonstrate the effectiveness of our technique through two case studies, where we show that the proposed interactive low-dimensional space constructions were pivotal for visualizing the high-dimensional data and discovering new patterns.
... In addition, it can be difficult for humans to visually compare arbitrary pairs of SPs that are distantly placed in the display space. Several studies aimed at selecting meaningful sets of SPs and effectively arrange them onto the display spaces [6] [30] [36] [38] [42]; however, these studies often had difficulty to visually compare large number of SPs. ...
... Suematsu et al. [33] also converted high-dimensional datasets into low-dimensional subsets and visualized these subsets using multiple PCPs arranged on display spaces based upon their similarity and correlation. Using similar ideas, Zheng et al. [42] selected SPs based upon the meaningfulness of the dimensions being displayed and adjusted their layout based upon their similarity. Claessen et al. [5] presented a technique to visualize high-dimensional datasets by selecting sets of low-dimensional subspaces and representing them as a combination of PCPs and SPs. ...
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Parallel coordinate plots (PCPs) are among the most useful techniques for the visualization and exploration of high-dimensional data spaces. They are especially useful for the representation of correlations among the dimensions, which identify relationships and interdependencies between variables. However, within these high-dimensional spaces, PCPs face difficulties in displaying the correlation between combinations of dimensions and generally require additional display space as the number of dimensions increases. In this paper, we present a new technique for high-dimensional data visualization in which a set of low-dimensional PCPs are interactively constructed by sampling user-selected subsets of the high-dimensional data space. In our technique, we first construct a graph visualization of sets of well-correlated dimensions. Users observe this graph and are able to interactively select the dimensions by sampling from its cliques, thereby dynamically specifying the most relevant lower dimensional data to be used for the construction of focused PCPs. Our interactive sampling overcomes the shortcomings of the PCPs by enabling the visualization of the most meaningful dimensions (i.e., the most relevant information) from high-dimensional spaces. We demonstrate the effectiveness of our technique through two case studies, where we show that the proposed interactive low-dimensional space constructions were pivotal for visualizing the high-dimensional data and discovering new patterns.
... Claessen et al. [2] visualized high-dimensional datasets by representing a set of low-dimensional subspaces as a combination of PCPs and scatterplots. Suematsu et al. [15] and Zheng et al. [22] also converted high-dimensional datasets into low-dimensional subsets and visualized these subsets using multiple PCPs or scatterplots respectively. These techniques did not provide rich interaction mechanisms to freely select the numbers of dimensions. ...
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... Tables are familiar and popular for investigating and getting acquainted with planning data, and scatterplot is one of the most frequently used multidimensional data visualization techniques (e.g. Zheng et al., 2015). Besides tables and scatterplots, bar charts (histograms) are widely used visualization techniques. ...
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