Traditionally, it is widely accepted that measurement error usually obeys the normal distribution. However, in this paper a new idea is proposed that the error in digitized data which is a major derived data source in...Traditionally, it is widely accepted that measurement error usually obeys the normal distribution. However, in this paper a new idea is proposed that the error in digitized data which is a major derived data source in GIS does not obey the normal distribution but the p-norm distribution with a determinate parameter. Assuming that the error is random and has the same statistical properties, the probability density function of the normal distribution, Laplace distribution and p-norm distribution are derived based on the arithmetic mean axiom, median axiom and p-median axiom, which means that the normal distribution is only one of these distributions but not the least one. Based on this ideal distribution fitness tests such as Skewness and Kurtosis coefficient test, Pearson chi-square chi(2) test and Kolmogorov test for digitized data are conducted. The results show that the error in map digitization obeys the p-norm distribution whose parameter is close to 1.60. A least p-norm estimation and the least square estimation of digitized data are further analyzed, showing that the least p-norm adjustment is better than the least square adjustment for digitized data processing in GIS.展开更多
WEN 我国的汉字究竟有多少?常用字、次常用字各有多少?(陕西新安机械厂任之功) DA 我国的汉字究竟有多少,这是一个目前还难于准确回答的问题,因为,长期以来,我国的汉字随时随地增加,“生而不报”,有些字又随时失去作用,“死而不葬”。...WEN 我国的汉字究竟有多少?常用字、次常用字各有多少?(陕西新安机械厂任之功) DA 我国的汉字究竟有多少,这是一个目前还难于准确回答的问题,因为,长期以来,我国的汉字随时随地增加,“生而不报”,有些字又随时失去作用,“死而不葬”。人们在回答这个问题的时候,只能根据几部大型工具书的收字数量,说出一个估计数字。如《康熙字典》收字47,043个。展开更多
文摘Traditionally, it is widely accepted that measurement error usually obeys the normal distribution. However, in this paper a new idea is proposed that the error in digitized data which is a major derived data source in GIS does not obey the normal distribution but the p-norm distribution with a determinate parameter. Assuming that the error is random and has the same statistical properties, the probability density function of the normal distribution, Laplace distribution and p-norm distribution are derived based on the arithmetic mean axiom, median axiom and p-median axiom, which means that the normal distribution is only one of these distributions but not the least one. Based on this ideal distribution fitness tests such as Skewness and Kurtosis coefficient test, Pearson chi-square chi(2) test and Kolmogorov test for digitized data are conducted. The results show that the error in map digitization obeys the p-norm distribution whose parameter is close to 1.60. A least p-norm estimation and the least square estimation of digitized data are further analyzed, showing that the least p-norm adjustment is better than the least square adjustment for digitized data processing in GIS.
文摘WEN 我国的汉字究竟有多少?常用字、次常用字各有多少?(陕西新安机械厂任之功) DA 我国的汉字究竟有多少,这是一个目前还难于准确回答的问题,因为,长期以来,我国的汉字随时随地增加,“生而不报”,有些字又随时失去作用,“死而不葬”。人们在回答这个问题的时候,只能根据几部大型工具书的收字数量,说出一个估计数字。如《康熙字典》收字47,043个。
