Mean and standard deviation versus median and IQR | AP Statistics | Khan Academy

Learn to choose the "preferred" measures of center and spread when outliers are present in a set of data.

AP Statistics on Khan Academy: Meet one of our writers for AP¨_ Statistics, Jeff. A former high school teacher for 10 years in Kalamazoo, Michigan, Jeff taught Algebra 1, Geometry, Algebra 2, Introductory Statistics, and AP¨_ Statistics. Today he's hard at work creating new exercises and articles for AP¨_ Statistics.

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[ianrjm]

I've read so many articles and watched so many videos, but this is the first one that turned the light on and help me understand. Thank you.

[jarrettortega]

I Honestly think that this man, Oh sorry Genius! is a excellent explainer. You are much better than any of my Teachers

[ahugebean]

This just all made sense. This helps a lot. Thanks a lot

[rontgenriesie]

Super informative, just what I was looking for thanks a lot.

[natalietucker]

Do you always use IQR as the measure of spread if median is the best measure of central tendency? Is this even if there aren't any outliars?

[ashah]

What is the difference between MAD and Standard Deviation?

[lennartka]

The Standard Deviation would be 66.046; you divided 34897.56 by 9; however the formula states n-1. Since there are 9 numbers n=9 --> 9-1=8

[natalie_lau]

Do you know what happens when there are 2 data sets, and one of the IQR is greater than the other? SO like, what does it mean when there is a high IQR vs. a low IQR?

[ariah]

can I just tell you I'm passing all my college math classes with A's because of you

[Arbitrageur_]

You didn't even touch on what the value of the SD represents on the chart. So you get a 75%