什么是mean error和mean squared error?

什么是mean error和mean squared error? the root mean square error Mean mean what 's mean what 's mean What's your mean? what 's that mean? mean什么时候加s totally suckwhat's mean? What's up?mean? lashkar ,what's mean mean什么时候加s mean和meaning what's the mean 和 what's the meaning 有什么区别`what's the mean of That's all mean to What is h's mean what is BMW's mean? What's the DOZ mean?