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<DIV><FONT face=Arial size=2><SPAN
class=239441702-04082007>Hi,</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2><SPAN
class=239441702-04082007></SPAN></FONT> </DIV>
<DIV><FONT face=Arial size=2><SPAN class=239441702-04082007>Every time I use
g_msd to calculate the MSD for one group, this program always output the
diffusion constant like</SPAN></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2># D[ SOL] =
0.4996 (+/- 0.0366) (1e-5 cm^2/s)</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><SPAN class=239441702-04082007><FONT face=Arial size=2>I know that g_msd
calculates the D using the least square (LSQ) method. But I dont know how to
calculate the deviation of D. In this case, how does g_msd get +/- 0.0366?
Although I got the exactly same D value using LSQ, I failed to
reproduce this deviation value. I know maybe it is very simple, but I have spent
considerable time without success. Can anyone explain how to calculate it from
the angle of mathematics so that I can easily reproduce the deviation of
D?</FONT></SPAN></DIV>
<DIV><SPAN class=239441702-04082007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=239441702-04082007><FONT face=Arial size=2>Thanks in
advance,</FONT></SPAN></DIV>
<DIV><SPAN class=239441702-04082007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=239441702-04082007><FONT face=Arial size=2>Zhongqiao
Hu</FONT></SPAN></DIV>
<DIV><SPAN class=239441702-04082007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=239441702-04082007><FONT face=Arial size=2>National University
of Singapore</FONT></SPAN></DIV></BODY></HTML>