when do we and why do we implement MEAN DEVIATION or also known as the AVERAGE DEVIATION? aside the difference in formula compare to STANDARD DEVIATION, when is it more appropriate to use one over the other?

Question

nincompoop · Answer

I am doing a little bit of research for my physics report analysis.  There are some materials on the internet that provides their definitions, but they aren't succinctly compared for my level of comprehension or use.   This is not a requirement, but I am doing it to learn more for my own sake.  

The instruction in my lab book clearly wants me to use "mean deviation," but I recall from my past chemistry labs that identifying errors and precision in measurements is done more accurately with standard deviation.

nincompoop · Answer

calling help from math whiz, number crunchers, statistic savants and experts.

zale101 · Answer

start tagging @nincompoop

chmvijay · Answer

@ganeshie8 @Hero @Directrix have a look at this

e.mccormick · Answer

THis looked useful on it: http://www.physicsforums.com/showthread.php?t=318193