Huh? What? Leak =12 Max = 14.4, BUT Median = 0

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Physician
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Huh? What? Leak =12 Max = 14.4, BUT Median = 0

Post by Physician » Thu Aug 21, 2014 4:36 pm

My sleep doc used ResScan for a six month summary from the S9 SD card. AHI = 0.1.

LEAK
median 0.0 95th %ile = 12 Maximum = 14.5

PRESSURE
median = 7.8 95th%ile = 10.4 Maximum = 10.9

I need to go back to high school math because I cannot understand the median values in the Leak and Pressure. How can the median be zero ?

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englandsf
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Re: Huh? What? Leak =12 Max = 14.4, BUT Median = 0

Post by englandsf » Thu Aug 21, 2014 4:39 pm

As I understand it, the way the software is calculating "median" is from the commonest value of all the data points it collects.

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palerider
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Re: Huh? What? Leak =12 Max = 14.4, BUT Median = 0

Post by palerider » Thu Aug 21, 2014 4:46 pm

englandsf wrote:As I understand it, the way the software is calculating "median" is from the commonest value of all the data points it collects.
that would be *wrong*

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palerider
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Location: Dallas(ish).

Re: Huh? What? Leak =12 Max = 14.4, BUT Median = 0

Post by palerider » Thu Aug 21, 2014 4:49 pm

Physician wrote:My sleep doc used ResScan for a six month summary from the S9 SD card. AHI = 0.1.

LEAK
median 0.0 95th %ile = 12 Maximum = 14.5

PRESSURE
median = 7.8 95th%ile = 10.4 Maximum = 10.9

I need to go back to high school math because I cannot understand the median values in the Leak and Pressure. How can the median be zero ?
for those of us that skipped stats in school, (including me) our resident math professor has written up a remedial stats course:
http://adventures-in-hosehead-land.blog ... de-to.html

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Accounts to put on the foe list: dataq1, clownbell, gearchange, lynninnj, mper!?, DreamDiver, Geer1, almostadoctor, sleepgeek, ajack, stom, mogy, D.H., They often post misleading, timewasting stuff.

bv1800
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Re: Huh? What? Leak =12 Max = 14.4, BUT Median = 0

Post by bv1800 » Thu Aug 21, 2014 5:33 pm

If you were to line up all of the readings, in a column, then sort the column in either ascending or descending order, the median would be the one that's exactly in the middle of the list (take the average of the two middle ones, if you have an even number of readings).

For example, if you have readings of
0
0
0
0
0
0
0
0
6
9
14.4

then the median is 0, but the max if 14.4 (not sure what Leak measures, so I can't comment on it).

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