Which Value to Use: % Discrepancy or Standard Deviation?

[August Lee]

I did an experiment about interference of light when it passes two slits. I got datas and made chart, but I'm confused which result value I need to use whether % discrepancy or standard deviation. My data's & discrepancy is around 7, and difference between theoretical value and experiment value is less than one standard deviation. How can I state about this experiment? I know their concept but I cannot utilize them :(

Thanks in advance!

 

[Dale]

That is largely a judgement call. I usually do a normal qq plot on the data and another on the log of the data (essentially the percent discrepancy). If the log transformed data is much more normal then I will use it, but if they are about the same then I will use the untransformed data.