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Percentages in Stats - Printable Version

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Percentages in Stats - Columbiabill - 02-02-2023

I have not been able to find it in the help guide.  What do the percentages mean under the statistics.  For example last night under leak I posted Min = 0, Med = 7.20, 95% = 15.6 and  99.5% = 27.6. I am guessing the Med = average?   
The MyAir App showed 13 L/Min which doesn't match the Med=7.2.  TIA

RE: Percentages in Stats - Gideon - 02-02-2023

Welcome to the forum.
Med does not equal average.
Med is the middle value of all values recorded with an equal number of samples above and below it.
Average is the sum of all samples divided by the !umber of samples

Percentage values are the value that xx% of samples are at or below that value.

Max is not used and a very high percentage is used instead to suppress posting totally unrealistic values that likely are an electronic spike. I believe you can change this in preferences.

RE: Percentages in Stats - pholynyk - 02-02-2023

Med is short for Median, which means there are as many values above this value as below. It is the same as the 50th percentile value. This is different from the average, which is the sum of all values divided by the number of values.

The other items - 95% and 99.5% are percentiles, for which there is no convenient symbol. They mean that out of the total collection of values, 95 % (or 99.5 %) fall below the given value.

I don't know if that is any clearer than the Wikimedia article on percentiles... Big Grin

RE: Percentages in Stats - Columbiabill - 02-02-2023

Makes sense to me.  Thank you.