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Re: Mode???? [message #13988 is a reply to message #13984]

Wed, 13 January 1999 00:00

Robert S. Hill
Messages: 11
Registered: January 1998

Junior Member

On Wed, 13 Jan 1999, Lisa Bryan wrote:
> Mode refers to the most likely value in an array. The method that
> jumps to mind is using the histogram function. The mode is the value
> associated with the max of the histogram. Is there anything slicker
> out there?

Getting a good estimate of the mode is not trivial. If you don't have
lots of counts in your histogram, either it will be noisy near the peak
or you will have to use such a big bin size that the quantization error
in your estimate is large. Two approaches that I have seen are to fit a
function (e.g., gaussfit) to the histogram, or to forego the histogram
altogether and to use the estimator mode=3*median-2*mean. (I don't have
a reference for the question under what conditions the latter formula is
applicable; my ancient CRC Tables lists it without further comment as
"Empirical Relation Between Mean, Median, and Mode," so presumably the
distribution should have a sort of skewed Gaussian shape.)

Bob

--
Robert.S.Hill.1@gsfc.nasa.gov Phone: 301-286-3624
Raytheon ITSS / Code 681, NASA/GSFC, Greenbelt, MD 20771

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[Message index]

		Re: Mode???? By: f055 on Thu, 14 January 1999 00:00
		Re: Mode???? By: Robert S. Hill on Wed, 13 January 1999 00:00
		Re: Mode???? By: lbryanNOSPAM on Wed, 13 January 1999 00:00
		Re: Mode???? By: rivers on Wed, 13 January 1999 00:00
		Re: Mode???? By: steinhh on Wed, 13 January 1999 00:00

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