Standard Deviation and Standard Error of the Mean

This video describes the differences between standard deviation and the standard error of the mean, and how they can be used to interpret data when the values are plotted as error bars on a graph.

[@his198]

Thank you very much for this video! I can't imagine a more clear explanation

[@PiersSupport]

Thanks Lena, I am glad you found it helpful!

[@deeplearning2552]

Kevin Piers what I don't understand is where does the number 6.33 at 4:18 come from?
Standard deviation of a list of red-colored numbers (averages from 12 experiments with Jack, on 3:40), that is of [100, 101, 99, 114, 103, 101, 95, 99, 95, 105, 100, 93], is not 6.33 but 5.25. I've checked with Python with numpy, by hand, and using online SD calculators. All give population SD as 5.25 and sample SD as 5.48.

[@Tyokok]

same calc results. asking too.

[@KandMwedding]

it's because he has messed up a lot in this video. the s.d. of the first 5 trials listed for jack is 14.14 (not "16" as he claims later). and the SEM of *that* set is 6.32. so i assume that's what he was referring to with "6.33." ..as for the rest of the video, it's also not a very good explanation of a simple concept: i.e. that you can have quite variable data (say flipping a coin and calling heads "0" and tails "1") which could have a large s.d. no matter how many times you measure it (for the coin example it will approach 0.5 as the number of random flips grows), but nevertheless the uncertainty in the mean itself (represented by the SEM) will tend toward zero as you make more and more measurements, irrespective of how noisy those data are.
the video could've used a better example (for instance, a person running anywhere is not a good example of independent data, as there could be trends in either direction -- faster or slower -- depending on the time between trials; thus these data are not even appropriately lumped together like this) and as you point out, he could've at least double checked his math before posting.

[@winvictorywin5612]

Piers Support
Hello sir,
I am having airborne dust concentrations data as PM10, PM2.5, PM 1 .
These data was taken before and during dust producing work in a civil construction site.
N=5
How can i compare these before and during operations data ?
It seems that there is percent variation in dust concentrations in atmosphere between before and during operation data based on particle size.
Before operation:
PM 10 ( particle size less than 10 microns) is sharing 40% of total airborne dust, and PM 2.5 ( particle size less than 2. 5 micron) shares 10% of total airborne dust.
During machine operation:
PM 10 shares 60% and PM 2.5 10% only.
It seems that PM 10 share is increased due to that machine operation?
Which test is suitable for analysing these type similar data for discussion ?
How to use statistics?
Any comparison among these particle sizes?
thank u.

[@davidrosen5137]

Four semesters of graduate level statistics, and you accomplished in 10 minutes what four different profs failed to accomplish at all. Thank you!

[@katomoon6170]

No better explanation than this one. Can't thank you enough Dr. Piers. You're an exceptional instructor with the ability to clearly, precisely and simply explain very complex statistics topics. God bless you. Much appreciation from Uganda - East Africa.

[@quintonwilson8565]

This is thee single best video on this subject on YT, thank you Dr. Piers.

[@jessicafb5398]

Thank you for explaining this concept so clearly and with great humor. Very helpful and enjoyable!

[@emmayu1847]

This is the best statistics video I have seen. Such clear explanation and great presentation. Thank you!

[@devong4722]

You have a gift. Needed to brush up on a few of these for a class and this was concise yet coherent. Thank you so much!

[@cajogos]

Really good refresher to these statistics ideas, I had completely forgotten what standard deviation and SEM was! Thanks a lot!

[@aziziqbal2777]

Most clear explanation on this topic I have seen on youtube. You've earned yourself a subscriber.

[@Mamatin2]

This was so great! Thank you, Dr. Pierce!

[@vikkirossiter]

I'm doing a stats class now and I understand more from this 10 minutes than the whole lecture on it. Much thanks

[@SmokeyHooder]

Watched this three times and finally I understood this. The best explanation I have found on this topic, no doubt!

[@NiekVink]

Finally a clear video on SEM, this helped a lot. Thanks!

[@cindybokish1534]

Thank you! Appreciate you taking time to explain. I cannot say how much this helped me.

[@dinglixi5179]

This solves my question which bothers me for so long. Thank you so much!

[@josephinetityiwe4434]

Thank you very much for enhancing my understanding of SD and SEM.

[@lensmaticoptical4083]

Thank You Sir. It is a best explanation ever i have seen on this topic. Amazing... God bless you.

[@soknya]

I need to watch it twice to confirm my understanding. Thank you for a clear explanation

[@JaqulinePrabu76]

Unreasonably good...great presentation!!

[@xuul7338]

Great video! Thanks for sharing, this was clear and concise.

[@dr.renupoonia5337]

very simple but effective way to teach these two terms and their use. Thanks a lot.

[@manikant1990]

Excellently explained, please make more videos of these sort in statistics and any other topic. :) Great job again!!

[@prakash_kp3039]

Thats a great , concise and holistic video.

[@akshu251]

Sad that I watched it too late. But as it is said, better late than never. Amazing video. Now, I will never forget the difference. Thank you.

[@912sonic]

I'm glad I found this too. Better late then never honestly

[@futurefee1444]

Excellent breakdown, thank you for your service.

[@belal7490]

Thanks very much Dr. Pier for your efforts.
This is a very useful video.

[@SaberNezumi]

A really good explanation. Thanks for the video.

[@jamesrobertson9149]

This is a brilliant video because it makes clear what the SEM is. first class! thanks.

[@mohammedalqahtani2643]

Truly you made it so simple and easy, Thanks!

[@andrewlukkuz369]

Thank you for making this video, I have a chem quiz on this and for some reason I couldn't wrap my head around the subject, your video helps alot bro.

[@michellexhg6077]

finally the video that answered all my questions! good job and thank you 💪🏼

[@neerajrokaya1132]

subscribed just after seeing this video..cant explain how aewsome this explanation is

[@p_mouse8676]

I always explain it this way to students. SD is a measure of how big the spread is between samples. SEM is a measure how exact we know the average (or mean). It starts to get interesting when SD is relatively big. At that point one could argue how valid the test actually was. Because it's perfectly possible that the SD is very big (individual samples are widely spread) but SEM is quite small at the same time.

[@user-pv5lg7hr1w]

You are a very good teacher and that is very rare nowadays.

[@okiwahboris1597]

Thanks for the video, i really understood much today, and i am defending my DVM tomorrow. God bless you

[@dheerajvarapana1124]

Fantastic explanation. Thanks a lot for your time and help.

[@adatse51849]

Very informative and perfectly explained!

[@quanzhaohe1221]

Very clear explanation! Thank you!

[@noazamstein]

Awesome video! so clear and concise

[@ZhigaZhega]

Thanks man, most helpfull explanaton on you YT.

[@navymcz]

Great video! Very well explained!

[@itssmsn91]

Thanks for the video with such a nice explanation :)

[@Selorm4christ]

Thanks very much. This info is statistically a life challenger.

[@ayabulelamkutswana2110]

watching this and I have a submission in two days, really helped thank you Doc!

[@oliverbird8320]

You explained so well on the concept!!!!!!!!!!

[@lllMrKrobylll]

Very nice and clear video. Thanks a lot!

[@wilsonvuong8855]

This is without a doubt the clearest video on SEM. Thank you so much for your efforts.

[@NiekVink]

agree!

[@jonelabutyte6617]

very good and quick refresher of SD and SEM evaluations❤ Thank you!!!

[@amirnashed9701]

great and very clear explanation, thank you

[@MDMAx]

Thank you for the clear explanation!

[@THE______TRUTH]

idk why but I laughed at the example of examining the data of Jack and jill who ran up the hill.

[@logjonbudha137]

This video is most important for the understand of S.D.& S.E
.Thnku so mush sir!!

[@luisborgesjr]

This man really knows his stuff!

[@gehuishen5415]

Very clear explanation!

[@mateom6596]

what a lucid explanation. thank you.

[@Tennischik93]

Absolutely brilliant, thank you!

[@ramzyhedia1277]

Thank you very much for taking the time and effort to prepare this is a really very interesting and useful video. God bless you

[@sarahbronte3043]

that's is really a simple access to the two complex concepts, thanks, that's really helpful for the psychology student without a math background to understand. you really knows what we are confusing in each steps.

[@ahmed_shawa]

Thank you very much! This was really helpful.

[@harikishanbusa4714]

Best explanation! much thanks.

[@lesliehermann7267]

That was SO helpful! Thank you!

[@drswetaruparel]

Thanks a lot for such a helpful video !!! 👍

[@miladiouss]

You create intuition, something that other videos don't.

[@GT-hj7ko]

Thank you great video and an excellent explanation of 5/5

[@aceplusplusplus7652]

Thank you Dr Piers!

[@genevieveperdue8019]

Thank you so much, this is a wonderful tutorial. I am a TA for a data analysis course and was having the hardest time figuring out how to emphasize the difference between SD and SEM. You did it very clearly and simply!! You just saved my students from a very confusing lab explanation :)

[@PiersSupport]

Thanks for the positive comment Genevieve! I'm glad you found it helpful.

[@yaswanthbangaru9116]

An Incredible way to put it!

[@arwabaabdulla9272]

Thank you very much for your clear explanation

[@ozgekrklk4718]

he is explaining very well , thank you

[@chitritaghosh4279]

Thank you very much for the video. I am a medical student. I needed a understanding of the difference between SD & SEM for community medicine. Your video helped me a lot...

[@dreamliner707]

That explanation was so clear. Thank you.

[@MrEndocytosis]

Nice video thanks! Would you say in general that when a single person does the same test repeated times (person running a mile 5 times) you should show SEM but when you have a group of people that do the same test such as a team running a mile, then you show the SD?

[@brookesullivan6663]

This was such a helpful video thank u so much

[@JasmineFarhan]

Wow that was really really really helpful!!!!! Thanks so much

[@VaibhavYawalkar]

best video on this topic. Thanks a lot sir.

[@user-kr7yc4cb3k]

This made me clear. Thanks !

[@user-uh9gg5dc5k]

GRACIAS!!!! Well done! Clearly and cleverly stated.:)

[@amosbako3981]

Thank you for this video, it's a must-watch for statistic student

[@sujanbandyopadhyay8895]

Fantastic video.

[@sekhothalimphafi6677]

wow! Thank you so much Dr Pierse

[@FoodHealthFit]

Great explanation, thank you

[@ammarparmr]

Wonderful video!

[@anirudhsood2006]

Thank you so much for the video.

[@ritachaudhary5780]

Thank you!
Well explained

[@movement9192]

Excellent explanations of sd and adm

[@swastiksanmay2315]

Nothing more nothing less Simply Awesome.

[@tiannamamo5862]

Thank you, thank you, thank you. Very helpful

[@KishorePenumuru]

Fantastic!! so clear!!

[@pig_samurai]

You are my angel~ Mr. Kevin thank you!

[@cbrewster10390]

THANK YOU. I have consulted 10+ sources trying to figure out the difference and was beginning to feel like a complete idiot until you.

[@longjamboris1041]

very helpful video. thanks again

[@ansariarbaz3374]

Just superb❤️❤️🔥🔥

[@nandiniB11]

Excellent explanation

[@blackkissi]

well explained! Thank you

[@KostasGiotis]

Great video!

[@shyamopt]

Dr Piers, good job

[@subramaniank6360]

Clear explanation of standard error mean

[@joenyc]

holy shit thank you for this explanation. it all makes sense now!

[@PlazmaHunter]

you are insane my man much loveee

[@komawni6075]

Thanks, it was so clear .