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Flow cytometry Stats - Median, Arithmetic Mean, Geometric Mean (Oct/11/2007 )

After FCM, in the stats you can have median, arithmetic mean, and geometric mean. For my experiments, I just see the median value but I wonder what are the cases you consider artih mean, when median, and when geometric mean.

Can anyone help me with this blink.gif

-Bungalow Boy-

QUOTE (Bungalow Boy @ Oct 11 2007, 04:51 AM)
After FCM, in the stats you can have median, arithmetic mean, and geometric mean. For my experiments, I just see the median value but I wonder what are the cases you consider artih mean, when median, and when geometric mean.

Can anyone help me with this blink.gif


The decision to use median or mean depends on your experimental set-up and on how you plan to use the data. Generally I've found that flow cytometry data are reported using geometric mean. The geometric mean is more robust than the arithmatic mean, it is much less likely to be affected by outliers. The median is usually even more sensitive to outliers than the arithmatic mean, because it is nothing more than the 'middle' of a set of values. You can (and probably should) consult any good stats textbook if you're interested in how geometric mean, arithmatic mean, and median are calculated.

As far as what you "see" when you do your experiments, you can click on 'edit histogram stats' to change which stats are displayed.

-Cassio-

Thank U Cassio, I have gone through the theory part of statistics of them but was not clear. I referred some papers and some were using Mean Flourescent Intensity (Geometric) and RFMI while some used median fl. intensity. I was confused with that. You explanation helps a lot. Thank U

-Bungalow Boy-