Background The problem of visualizing a hierarchical dataset is an important and useful technique in many real-life situations.Folder systems,stock markets,and other hierarchical-related datasets can use this tech-niq...Background The problem of visualizing a hierarchical dataset is an important and useful technique in many real-life situations.Folder systems,stock markets,and other hierarchical-related datasets can use this tech-nique to better understand the structure and dynamic variation of the dataset.Traditional space-filling(square)-based methods have the advantages of compact space usage and node size as opposed to diagram-based methods.Space-filling-based methods have two main research directions:static and dynamic performance.Methods This study presented a treemapping method based on balanced partitioning that enables excellent aspect ratios in one variant,good temporal coherence for dynamic data in another,and in the third,a satisfactory compromise between these two aspects.To layout a treemap,all the children of a node were divided into two groups,which were then further divided until groups of single elements were reached.After this,these groups were combined to form a rectangle representing the parent node.This process was performed for each layer of the hierarchical dataset.For the first variant from the partitioning,the child elements were sorted and two groups,sized as equally as possible,were built from both big and small elements(size-balanced partition).This achieved satisfactory aspect ratios for the rec-tangles but less so temporal coherence(dynamic).For the second variant,the sequence of children was taken and from this,groups,sized as equally as possible,were created without the need for sorting(sequence-based,good compromise between aspect ratio and temporal coherency).For the third variant,the children were split into two groups of equal cardinalities,regardless of their size(number-balanced,worse aspect ratios but good temporal coherence).Results This study evaluated the aspect ratios and dynamic stability of the employed methods and proposed a new metric that measures the visual difference between rectangles during their movement to represent temporally changing inputs.Conclusion This study demonstrated that the proposed method of treemapping via balanced partitioning outperformed the state-of-the-art methods for several real-world datasets.展开更多
树图是一种实用的层次数据可视化方法,由于其数据属性和分析任务具有多样性,单种树图布局算法难以满足各层数据的显示需求.文中介绍了Slice and Dice,Squarified,Pivot-by-middle,Pivot-by-size,Pivot-by-split-size,Strip,Spiral和Orde...树图是一种实用的层次数据可视化方法,由于其数据属性和分析任务具有多样性,单种树图布局算法难以满足各层数据的显示需求.文中介绍了Slice and Dice,Squarified,Pivot-by-middle,Pivot-by-size,Pivot-by-split-size,Strip,Spiral和Ordered-Squarified 8种典型的矩形树图布局算法,给出了评价它们的6项性能指标定义,具体包括平均长宽比、连续性、可读性、平稳性、平稳的平衡性和距离相关性.通过实验,采用这6项性能指标对8种算法进行了比较分析,给出实验和分析结果.同时提出了多种布局算法混合使用的优化方案,并进行了优化后的指标分析,其结果可为树图布局算法的选择提供参考.展开更多
在很多领域的统计分析中,通常需要分析既具有层次结构又具有多维属性的复杂数据,如食品安全数据、股票数据、网络安全数据等.针对现有多维数据和层次结构的可视化方法不能满足对同时具有层次和多维两种属性数据的可视分析要求,提出了一...在很多领域的统计分析中,通常需要分析既具有层次结构又具有多维属性的复杂数据,如食品安全数据、股票数据、网络安全数据等.针对现有多维数据和层次结构的可视化方法不能满足对同时具有层次和多维两种属性数据的可视分析要求,提出了一种树图中的多维坐标MCT(multi-coordinate in treemap)技术.该技术采用基于Squarified和Strip布局算法的树图表示层次结构,用树图中节点矩形的边作为属性轴,通过属性映射、属性点连接、曲线拟合实现层次结构中多维属性的可视化.将该技术应用于全国农药残留侦测数据,实现了对全国各地区、各超市、各农产品中农药残留检出和超标情况的可视化,为领域人员提供了有效的分析工具.MCT技术也可用于其他领域的层次多属性数据的可视化.展开更多
文摘Background The problem of visualizing a hierarchical dataset is an important and useful technique in many real-life situations.Folder systems,stock markets,and other hierarchical-related datasets can use this tech-nique to better understand the structure and dynamic variation of the dataset.Traditional space-filling(square)-based methods have the advantages of compact space usage and node size as opposed to diagram-based methods.Space-filling-based methods have two main research directions:static and dynamic performance.Methods This study presented a treemapping method based on balanced partitioning that enables excellent aspect ratios in one variant,good temporal coherence for dynamic data in another,and in the third,a satisfactory compromise between these two aspects.To layout a treemap,all the children of a node were divided into two groups,which were then further divided until groups of single elements were reached.After this,these groups were combined to form a rectangle representing the parent node.This process was performed for each layer of the hierarchical dataset.For the first variant from the partitioning,the child elements were sorted and two groups,sized as equally as possible,were built from both big and small elements(size-balanced partition).This achieved satisfactory aspect ratios for the rec-tangles but less so temporal coherence(dynamic).For the second variant,the sequence of children was taken and from this,groups,sized as equally as possible,were created without the need for sorting(sequence-based,good compromise between aspect ratio and temporal coherency).For the third variant,the children were split into two groups of equal cardinalities,regardless of their size(number-balanced,worse aspect ratios but good temporal coherence).Results This study evaluated the aspect ratios and dynamic stability of the employed methods and proposed a new metric that measures the visual difference between rectangles during their movement to represent temporally changing inputs.Conclusion This study demonstrated that the proposed method of treemapping via balanced partitioning outperformed the state-of-the-art methods for several real-world datasets.
文摘树图是一种实用的层次数据可视化方法,由于其数据属性和分析任务具有多样性,单种树图布局算法难以满足各层数据的显示需求.文中介绍了Slice and Dice,Squarified,Pivot-by-middle,Pivot-by-size,Pivot-by-split-size,Strip,Spiral和Ordered-Squarified 8种典型的矩形树图布局算法,给出了评价它们的6项性能指标定义,具体包括平均长宽比、连续性、可读性、平稳性、平稳的平衡性和距离相关性.通过实验,采用这6项性能指标对8种算法进行了比较分析,给出实验和分析结果.同时提出了多种布局算法混合使用的优化方案,并进行了优化后的指标分析,其结果可为树图布局算法的选择提供参考.
文摘在很多领域的统计分析中,通常需要分析既具有层次结构又具有多维属性的复杂数据,如食品安全数据、股票数据、网络安全数据等.针对现有多维数据和层次结构的可视化方法不能满足对同时具有层次和多维两种属性数据的可视分析要求,提出了一种树图中的多维坐标MCT(multi-coordinate in treemap)技术.该技术采用基于Squarified和Strip布局算法的树图表示层次结构,用树图中节点矩形的边作为属性轴,通过属性映射、属性点连接、曲线拟合实现层次结构中多维属性的可视化.将该技术应用于全国农药残留侦测数据,实现了对全国各地区、各超市、各农产品中农药残留检出和超标情况的可视化,为领域人员提供了有效的分析工具.MCT技术也可用于其他领域的层次多属性数据的可视化.
