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Error bars for non-normal data

Hello JMP community,

 

I wanted to hear what statisticians believe is the best way to depict error bars for skewed data?

I have a non-normal distribution of measurements (mg of drug taken per a day across ~50 people across 3 days) and I have 3 groups of people. I'd like to make a line graph (not box plot) but I'm not sure what to put as the error bars. The main data points would be the median (not mean) amount of drug taken between the 3 groups of people at the 3 time points. Time would be the x-axis, mg of drug the y-axis.

 

Any suggestions on what's most statistically appropriate?

 

Thank you

AnalyticsGraphicsRe: Error bars for non-normal data

Sounds like you have a time series which may appear as a skewed distribution when the time component is collapsed.  Why not look at the data with a control chart? IR in JMP.  Or you could subgroup by groups of people, Or IR by Group)