Percentiles and Quartiles

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[@crazypolite]

10 years after you made it, still helping students (FYI) 👍🏻 Thanks man

[@MikeDiaz-mf4jz]

I love you too

[@gabriel-no4uh]

My professor couldn't explain this very well and neither could the book. This was so helpful, keep up the good work!

[@wakia7179]

What percentile would be 11? I hope u don't mind explaining

[@RebeccaUzoh]

I have a biostatistics exam tomorrow, this was a HUGE help, thank you.

[@MissWooHoo11]

+Rebecca Uzoh i have a stats one tomorrow as well! good luck!

[@SagarKumar-su3kb]

My DAR (Data analytics and representation) exam tomorrow too!

[@eliezerriveraeli6856]

Did you get a good grade?

[@RebeccaUzoh]

@@eliezerriveraeli6856 Yes I did!!

[@JimboPro]

I have a stats test tomorrow as well but in the present

[@okuu_utsuho]

That's way easier than what was thaught to us in applied statistics. In our 1 1/2 hr class, the prof showed some k shenanigans where you can just find the 2 values near what you get from dividing percentile by 100 then multiplying it with n+!

[@kuknisti]

You explained it so clearly, thank you.

[@euscieu4246]

Thank you very much! You've helped me so much. I love how concise but extremely helpful your videos are. Subscribed :)

[@HealthGuy_]

I have a Medical stats test in 3 hours. This helped!!!

[@v-bay]

literally better explanation than my college professor and his notes. Professors make these things seem so complicated with other useless information

[@school-zm4hm]

bro I know, my college professor is so ass at teaching us it sounds like gibberish

[@mariyaasghar7539]

thank you so much .. I answered a couple of my community medicine questions in my exam thanks to this video

[@occupiedusername]

Explained everything I never understood neatly and quickly. Wonderful!

[@kyedae9066]

jeez i cant believe u are probabaly near or in 30s now

[@occupiedusername]

@@kyedae9066 31, and now a PhD student working with statistics every day!

[@The_Sw0rdman]

@@occupiedusername are you still alive ?

[@shellielewis8387]

Very clear and direct, thank you! ♥

[@craiglistly8210]

thank you. did a good job covering the important things.

[@thinkinle]

thank you so much for carrying me through statistics.

[@ysynha9]

I Can~t believe I learned it in 3 min, thank you! haha

[@roselover02]

Like my channel for more

[@brazwen]

I'm a visual learner and this helped a lot. Thanks (:

[@hhyyatt]

it is so clear. Thanks for your time.

[@diana_me_021]

LOVED it, thank you!

[@veronicaibarra4651]

you made it soooooo simple! Thanks!!!!

[@PreyaMia]

This was great, it really helped me out a lot :)

[@MrChadhatarun]

thank you soooooooo much for making the understanding so easy

[@antwaun123]

Thank this really helped me a lot!

[@shealyngillaspy3711]

this was so helpful! made my homework much easier

[@Typewriter_z]

wow, you made it so simple, thanks!

[@ricardovera7383]

You explained something in 3 minutes that a class wouldn't do

[@comdymaster2163]

this was really helpful video thanks alot man

[@minhucbui9566]

Thank you, it still works in 2021

[@Coachvinoo]

This was a last minute help for my stats exam, thanks very much!

[@queenpree4399]

his was very helpful. Only question I have is why do we use the 5th and 6th value to get the average?

[@AD-yq8rl]

Thank you soooo much , I really appreciate 🙂

[@studyinnorwayandeurope2837]

So clear, thank you.

[@fincy8309]

Thank you so much. You made my day.... :)

[@apexlegends5440]

Reversing 1st formula and increasing one in postion gives 6th position In 2nd formula why 20+1?

[@jmsison7124]

This help me a lot ty

[@tarsier9241]

thank you so much this helped me a lot

[@ariukaa27]

quite helpful, thanks!

[@justicewolosin6602]

at 3:03, what if your data set is smaller and only has 4 numbers? What do you do about needing the 5th and 6th values of the data set?

[@francief9660]

I love you!!! So helpful

[@gwenramos6111]

Thank you so much for this

[@rvandeep]

brilliant explanation .. :-) simple ... thank you

[@jordangolden3985]

thanks this was really helpful

[@yaseeenali636]

Thank you professor

[@Elaine-rb6kk]

Thank you sooooo much!

[@MsPrincesz101]

That was helpful! thank you!!

[@ErikRuvalcaba]

Great video. I don't expect you'll answer as this instructional is quite old and out of your thoughts. But I ask anyway for the benefit of the community here. What would you do if your 5th value had been, say, 4? The average there is 4.5, which is still not a value you in your data set. Would a legitimate answer be? Would you round (as one exchange here opined)?

[@centurychallenger]

Thank you very much.

[@chpervaiz1876]

Thanks.. it is quite helpful :)

[@jbzynga]

Simple and elegant !!

[@PaperClipFlip]

Could you briefly explain why the formula to obtain the Value # is the way it is?

[@amanday3103]

For the part a 2:58. What if you get an odd number and your mean is a fraction that is not part of the data set? Would you round?

[@Nguoitinh100nam]

Thank you very much

[@forexcitycapital4293]

If we followed the same definition it means that when ask what is the quartile or 25 percentile ranking at? We mean what is the rank of the number 5 since it lays after 5 numbers from a population of 20 ? 20/4 the two example you have provided are deferent !

[@proce1193]

Thank you so much!!!!

[@benedictekitenge6155]

thank yo so much for this explanation

[@sniper786oghul]

this video very understanding helpfully

[@iitzeazie2900]

Short and meaningfull thank you

[@anadiajaghai801]

I hope this helps me with my test tomorrow. I have a better understanding of the topic but I'm still a little shaky. Thanks overall tho. 😁

[@MsPerva]

Great, thanks 🌹🌹🌹

[@hisetenespanolbysara6556]

In the 25% sample, what does the number 1 in the parenthesis represent?

[@sniper786oghul]

nice video thank you very much

[@helloWorld29138]

short yet consice and clear 👍👍👍👍

[@as24836]

Yeah, brief and çlear. Thanks ıt just was what ı looking for

[@queenpree4399]

This was very helpful. Only question I have is why do we use the 5th and 6th value to get the average?

[@kannan2052]

Because the value is 5.25th number..that means between 5th and 6th value..thats why we take the avg….i am literally replying after a year…pardon me

[@sabtainshah8986]

is it necessary to arrange data in ascending order

[@SagarKumar-su3kb]

Thank you a lot! You saved me from failing tomorrow's exam. My teacher Usha is too stupid. She took an hour to explain the same thing and most students in my class were unable to understand it.

[@mrbeastindia8660]

iitm online degree?

[@SagarKumar-su3kb]

@@mrbeastindia8660 Nope, she was a faculty at my college. I am sure you're talking about Usha Mohan right?

[@mrbeastindia8660]

@@SagarKumar-su3kb yes the statistics teacher, i have enrolled in the degree and she's my stats teacher

[@SagarKumar-su3kb]

@@mrbeastindia8660 enjoy your stats classes

[@elvynr.7358]

So if what if I find the mean of the 5th and 6th percentile and still get a decimal? What do I do then? Round?

[@flippy08100]

How did the equation that multiplies percentile with (n+1) come about, how did anyone come up with this, how does it even work. I feel like this is the most important bit about maths, because you can't only use given equations as tools

[@ptronilomatias5319]

compre ko sa saturday.. i hope this lesson will help me

[@hellamilles4419]

My uni textbook gave such an overcomplex way of finding percentile values that I totally forgot there was such a simple way of finding it, i was getting ready to calculate category boundaries and cumulative percentages and all that crap 😅

[@ashtar.m]

SUPER helpful :) Thank you and God bless your soul (if there is a God n a soul ;)) THANK YOU again :)

[@ravloo]

After further thought, I feel that the only thing that needs to change here is the given definition for a percentile. Namely, the "boundary point" should be included. So something like this -- "A percentile is a value for which a certain percentage of values lie at or below." Otherwise...great explanation.

[@MsVamPireChic]

Wtf! When I did that p/100 * (n+1) thing I got 6.5 so then I rounded up to 7 and if I go between the 7th and 8th number in my list, I get 18, but that doesn't make any sense because if I do it on my TI-84, it says the 25th percentile is 15! I did it another way by doing (.25)(25)=6.25, rounded down to 6, and went in between the 6th and 7th number and got 15. So this way makes no freaking sense!

[@mohammed130nazer7]

what is the percentile ranking of 11 ?

[@ravloo]

Is there a contradiction here? In this video it's stated that 5 is the value corresponding to a 25th percentile ranking. If I understand the given definition of a percentile correctly, this would mean 25% of the elements should fall below the value 5. However this is false, since only 20% of the elements in this set fall below 5.

[@maryam000002]

Thank you that's helpful :)

[@lucybuckley8674]

how does it work that 10 has the ranking of 80% but using the second formula, the 80th percentile lies at the 16.8th value which is between 9 and 10?

[@apexlegends5440]

In my book a question had percentile rank position 20 why he than took avg of 20and 21 or is it wrong in book?

[@evelynedagang5901]

🙏 thanks sir

[@mathhelpmadeeasy]

I liked the way this guy described it. A little different than the way I described it on my video

[@matthewreynolds8068]

Holy crap, this video is 10 years old?!

[@MathematicalMinds]

Why we add 1 sir

[@arabianchessfriends]

when you summarize 2 hours lecture in 3 minutes

[@codytaylor2914]

Why did you add 1 to n?

[@arjunrathi93]

This is wrong! the formula is basically for the location of the percentile. so if you get 5.25 then it means its between 5th and 6th location. so what you gotta do is multiply .25 by diff of location 5 an 6 and then add that value to location 5. lemme explain by an example! 0 0 5 7 8 9 12 14 22 33 now to calculate 25th percentile or 1 st quartile L(25)= (10+1)*25/100=2.75 this means that the position of the 25th percentile is 2.75 now, .75 more than 2nd position so .75*(5-0)=3.75 {5-0 because 2nd location value is 0 and 3 location value is 5 and percentile location is 2.75} now al you gotta do is add 3.75 to the 2nd location L(25)=0+3.75!

[@chpervaiz1876]

that is exactly what he told.. it is for VALUE NUMBER not the value..

[@mamtabkbk6292]

Hi.. I need help in statistics can you help me.

[@Biochem2k17]

why standard deviation is denoted by sigma

[@amartyamukherjee4298]

If more than a single person get the same marks, will the percentile of all of them holding the same marks will be same?

[@fillemonawala474]

finally i understand my topic...where ever we gonna meet,i will give you a hundred dollar

[@vipultawde6350]

Shouldn't 12 correspond to the 100th percentile in the list ?

[@aditidump]

why does the formula work??

[@rahrealofficial]

Waooo, amazing

[@offical_SolDERAN]

I didn't know hero's still existed.

[@eidm1801]

I love you bro

[@kyaiaiakyaiaia4230]

shouldn't have given up my notebook to someone, but whatever I have yt I don't need that today. I just wanna check when to add n(+1) because in the trimmed mean we don't add +1.

[@kyaiaiakyaiaia4230]

+Kyaiaia Kyaiaia so basically percentage and quartiles are the same thing we still add +1 to n. nothing is confusing anymore ..

[@Yumiesthetic]

Don't you round up 5.25 to 6 so you get the average of the 6th and 7th term? But then again it's still 5+5/2 so the answer is the same.

[@KrestenGiese]

So if the percentile is 5.25, I take the average of the 5th and 6th right? What is the 5th value is 5, and the 6th is 6. That means... 5 + 6 / 2 = 5.5. I am still left with a number that's not whole.

[@chroniclesblade9555]

No, you don't just round it off to 6 if the number is not whole you just need to round it off to the next number example 5.25 so 6 you don't need to get the average if the given is not whole number then just leave 5.25 be if it is a whole number then round if off to the next number hope it helps :)

[@pratyushchow6724]

why (n+ 1) when calculating 25% percentile

[@drwho8672]

cuz you start counting from 0 and not from 1.

[@musicjunkie8228]

It's the opposite of what you'd do when calculating the percentile. Try writing out the same percentile formula with the value number left unknown, with some easy algebra you'll get value = (percentile/100)*(n+1)

[@johnnyasdfaddad]

MusicJunkie Still can't get it....

[@swastikatiwari1390]

Because that is individual series

[@68216339]

Because we are finding the position. For any data, to determine the middle position we could use (n plus 1)/2. Because we are taking (n plus 1) × 50%. So in order to determine the position say the 25th percentile we could take 25% of (n+1).

[@aletheiarodriguez9101]

What 16 ➗ to 10 or 20 sir

[@jonpritzker9709]

Isn't 10 included in the percentile ranking? So it should be 17/20 *100percent, no?

[@svendubliano9919]

yay now i dont have to fail my grade 12 math exam tomorrow!

[@tylercochrane9404]

Sven Dubliano I need this for 6th grade online homework and I don’t get it at all

[@yasirhilal7814]

tq

[@seanmarkmira7694]

They have the same voice of seananners. Try to search it on youtube

[@hannahjuliagonzales6950]

@ 3:05 I don't understand how it became 5+5 shouldn't it be 5+6?