土地覆被遥感产品真实性检验方法对比

真实性检验是保障土地覆被遥感产品生产质量,支持土地覆被遥感产品应用的重要环节.土地覆被遥感产品真实性检验实践总与理论存在一些差异,其主要体现在用于检验的参考数据样本数量和空间分布两个方面,而这种差异对检验结果的影响还不十分清楚.以中国陆地范围为实验区域,GlobeLand30作为全样本参考数据,ESA CCI-LC作为...

Comparison of Accuracy Assessment Methods of Remote Sensing based Land Cover Products

Accuracy assessment is important for the application of land cover products. In practice， there are many differences for sample size and spatial distribution of the reference data used for accuracy assessment， and the impact of this difference on accuracy assessment results is not very clear. This paper validated the ESA CCI-LC using GlobeLand30 as the reference data in China. We test the impact of sample size， sampling model， and sample unit on the overall accuracy and various types of accuracy. The results are as following. Firstly， the sample size makes a difference to the accuracy assessment results. The overall accuracy based on point sample is close to that of the theoretical sample size while the sample size in half （about 600 sample points）， however， the sensitive degree of different classes of precision on the sample size is different， classes with low area weight are more sensitive to sample size， especially stratified random sampling used in the case of small sample size. Secondly， based on the theoretical sample size， the sampling model has little effect on the overall accuracy whether it is the accuracy assessment of point sample or cluster sample， but it has an impact on the accuracy of each class， especially the class with a small area weight. Finally， the stability of accuracy assessment of simple random sampling based on cluster sample is worse than the accuracy assessment based on point sample. The increase of the sample unit will increase the uncertainty of the accuracy assessment result on the basis of the theoretical sample size， with the increase of the sample unit， although the volatility of the accuracy assessment result becomes smaller， the result is still large compared to the point sample. Therefore， in order to reduce the uncertainty of the accuracy assessment results of land cover remote sensing products， the sample size can be increased for point sample， and the number of sample units can be increased or the size of sample units can be appropriately reduced for cluster sample.