送交者: 秦州刺史 于 2006-4-05, 14:00:41:

回答: 新到中xj关于error bar的解释有一问题 由 littlebird 于 2006-4-05, 11:13:02:

just like Rodger said:
"It is the same to prove sum of squares is smaller than
square of sum, given all elements are larger than 0."

But I didn't find a proof for Mean-SE>=X(min) and from
my simple Excel calculation, I found a counter example:

0.1, 0.1, 0.1, 9.e+13

Mean-SE=0.09765625, which is < 0.1.

Here, SE=SD/SQRT(N), and SD refers to the bias-corrected
variance,just like how Mathematica implements StandardDeviation[list]

Could this be due to numerical uncertainty?

• You only need to prove that when MIN(x) = 0 - wasguru (526 bytes) 2006-4-05, 16:41:40
  • hi, I was just thinking about you after all these people wrote - steven (116 bytes) 2006-4-05, 19:46:45
  • 谢谢指教 - 秦州刺史 (73 bytes) 2006-4-05, 19:21:21
    • 是，故儒的方法经常和别人不同，蛮有创意的 - xj (0 bytes) 2006-4-05, 19:27:34
• It is easy to prove (Mean-SE) greater than 0 given (在所有数据 \gt 0的前提下） - 秦州刺史 (0 bytes) 2006-4-05, 14:05:22

加跟贴