Outliers - Box and Whisker Plot (1.5 IQR)

Learn how to find which data points are outliers using a box and whisker plot. We discuss the method of working with 1.5 times the interquartile range to find out which data points are outliers. We also discuss how to construct a box and whisker plot by finding the median, lower quartile, upper quartile, maximum and minimum.
Jump to Section of this Video:
0:06 What is an outlier?
0:28 How to create a box and whisker plot
0:36 How to find the median
0:54 How to find the median when there is an even number
1:17 How to find the Upper Quartile and Lower Quartile
1:57 How to graph box and whisker plot on number line
2:33 How to graph the whiskers using the minimum and maximum
2:44 How to find the IQR (interquartile range)
3:08 Use 1.5 IQR to find outliers
Related Videos to Help you Succeed with Math:
Firstly, If you like my teaching style Subscribe to the Channel
bit.ly/Subscrib...
Algebra 2 Final Exam Review
• Algebra 2 Final Exam R...
Take Your Learning to the Next Level with me!:
Get my Learn Algebra 2 Video Course (Preview 13 free video lessons & learn more)
mariosmathtuto...
Learn Algebra 1 Video Course
mariosmathtuto...
Looking to raise your math score on the ACT and new SAT?
Check out my Huge ACT Math Video Course and my Huge SAT Math Video Course for sale at
mariosmathtuto...
* Organized List of My Video Lessons to Help You Raise Your Scores & Pass Your Class. Videos Arranged by Math Subject as well as by Chapter/Topic. (Bookmark the Link Below)
www.mariosmath...

[@pedroarellano4266]

I'm in an online class right now. You explained it much better in less than five minutes than they did. THANK YOU!!

[@botlhalekoloje9029]

I just found you and you explanation is better than my teachers 😸.

[@yurigd1]

That's the video I was looking for. Informative and cut-to-the-chase. A deserved thumbs up.

[@MariosMathTutoring]

Glad you liked it!

[@rainymatch]

the best vid on this specific topic so far, seen a couple. big up!

[@scottdiver690]

Good video, well explained, thank you.

[@MariosMathTutoring]

Glad it was helpful!

[@khaledmekkari2045]

Hi, great video, why do we multiple by 1.5 ? and not any other number.

[@diax7831]

it's a law

[@slim6476]

@@diax7831 but why

[@ookeybookey7955]

@@slim6476 MATH

[@slim6476]

@@ookeybookey7955 yes but why

[@ibeeyt-brawlstar4965]

@@slim6476is just a law, there is no why. I’ve been studying Statistics GCSE for a while, still don’t know why multiply by 1.5

[@IrinaHerreraYT]

Great video, thank you very much!!!

[@watimunthali607]

Very helpful

[@marvelmuziq]

youve saved my biostatistics exam

[@ivyyu6432]

Thankyou sir.

[@MariosMathTutoring]

Most welcome

[@basedchad534]

Bet Mario won't pin this comment

[@ob2065]

مشان الله لاقولنا ال mean !

[@athenaa.bosendorfer]

So if 60 is an outlier, do we take it out of the plot and just put a point there? And change the lowest value to 82?

[@ayahelhoussieny474]

question: why do you multiply 1.5 by the IQR?

[@aaronjuarez-cruz]

Idk a guy just mad that up I forgot his name though

[@aaronjuarez-cruz]

Correction we do that to see if we have any outliers

[@humparepatta]

Hey. Thanks a lot for the video. It is very helpful. I nevertheless have a question. As I understood: the outlier is regarded as an error and therefore not shown as the lowest value. However, its influence on Q1, Q2 and Q3 are still present, right? If we really threw it out, we would calculate a whole different box and whiskers plot. Shouldn't we be using such a new one?

[@EricLaspe]

It's still part of the data. In labeling a datum an outlier, we're not saying it was an erroneous measurement; we're saying it doesn't have as much predictive power as the rest of the data.

[@sbbperson]

where does 1.5 come from?

[@darrienxavier5536]

Straight to the point

[@jojoo_aah8072]

Finally I get it!!

[@hishamtarek4067]

MR JHONNY

[@keiniece9519]

You explained this perfectly. Thank you 😊

[@MariosMathTutoring]

Glad it was helpful!

[@shilpanavare7439]

Nice explanation. Why do we multiply by 1.5

[@_0920SSNN]

Did you find logical answer?

[@shilpanavare7439]

@@_0920SSNN no

[@BVfamily]

Awesome video. Brief and lots of info. Thank you!

[@MariosMathTutoring]

Glad it was helpful!

[@zapatobama8301]

thanks , but how do we deal with duplicated data? in this scenario for instance. Consider the following set of data;
0.87, 0.88, 0.91, 0.92, 0.86, 0.91, 0.90, 0.93, 0.82, 0.89, 0.87
Construct and interpret a box-and-whisker plot for this data

[@貴方を見てるよ]

doing god's work. keep it up

[@MariosMathTutoring]

Glad you like my videos!

[@TheLostEngineer-xb8iy]

Direct and short explanation, clear, very concise. That's just too perfect for a free video. Thanks!

[@MariosMathTutoring]

Glad it was helpful!

[@SocksforEdits]

I wish you were my teacher in my school!

[@alirezaalheli2226]

thank you 👍

[@MariosMathTutoring]

Welcome 👍

[@s_w_i_s_s_c_h_e_e_s_e]

Could you please post the formula down here?

[@theonepersonokay6966]

THANKS I needed this

[@Owlzon]

Great video , thank you

[@ruhikaragul3620]

birlliant thx much

[@yareshvijayasundaram7272]

Thank you!

[@abdulhamidalanany4398]

Thank you

[@aneeqa1001]

Thank you so much sir!

[@jaz3115]

Thank you so so much, saved me once again

[@MariosMathTutoring]

Glad it helped!