摘要
本文对不确定性可视化表达的主要技术与方法进行了简要论述,进而以北京市城市边缘带样区基于地统计学的土壤表层的pH空间预测作为案例研究,以相对误差表示预测结果的不确定性,应用色调-饱和度-亮度(HSI)色彩模型实现土壤属性预测结果和不确定信息的可视化同步表达。在HSI模型中,色调值被用来表示预测值,白度表示不确定性。在案例研究的pH预测输出结果中,颜色发白的区域表示预测结果的不确定性较高,需要做进一步补充采样。实际应用过程中发现,二维图例对不确定性的可视化表达效果有一定的限制作用,仍需在二维图例完善或创建新型图例方面开展深入的研究工作。图3参14。
Hue-Saturation-Intensity (HSI) color model, a psychologically appealing color model, was employed to visualize uncertainty represented by relative prediction error based on the case of spatial prediction of pH of topsoil in the peri-urban Beijing. A two-dimensional legend was designed to accompany the visualization-vertical axis (hues) for visualizing the predicted values and horizontal axis (whiteness) for visualizing the prediction error. Moreover, different ways of visualizing uncertainty were briefly reviewed in this paper. This case study indicated that visualization of both predictions and prediction uncertainty offered a possibility to enhance visual exploration of the data uncertainty and to compare different prediction methods or predictions of totally different variables. The whitish region of the visualization map can be simply interpreted as unsatisfactory prediction results, where may need additional samples or more suitable prediction models for a better prediction results.
基金
Under the auspices of Knowledge Innovation Frontier Project of Institute of Soil Science,Chinese Academy of Sciences(No.ISSASIP0716 )
the National Nature Science Foundation of China ( No.40701070,40571065)