Stuck on standard deviation?? This video will help you understand what that crazy formula really says.. Watch a few times if necessary... "THE AVERAGE DISTANCE TO THE MEAN!!" *sort of... How to think of this measure of spread...
I did not know how fast the 17 minutes went away!!! I could understand and will permanently remember the concepts taught!!! Extraordinary teaching.. You are unique and energetic... keep up this way.. do not change based on some tasteless comments ... you are one of the best teachers who can keep the audience entertained while they learn it really well!
On hearing the kids in the background (in what I assume is his house): "Oh, thank god, this guy has reproduced." We need more math profs like this! Thanks so much!!!
I like how you did this video. We need more people like you. Some professors are just so boring and I feel like I'm falling behind cuz they explain so poorly. But your examples are fun and keep me awake! LOL
Same here, I can not understand a thing my BSTAT teacher says because he is Indian and he just reads right from the power points, but I understood this.
I'm going to watch every video you've posted. This was such a huge help! I love the humor, the energy, the entertainment, and (mostly) the approach to teaching. It's brilliant!
Thank you MrNystrom, your teaching style is very upbeat and has a great pace. I wish my college professors had half of your talent when it comes to teaching. I'm watching your videos for my business statistics course and I'm really enjoying how you simplify the material. Again, thank you so much and keep up the great work!
I think he is teaching children and your idea of a clown is what children like. In fact, having a straight face while teaching is the most disengaging way of teaching - even for adults. Did you try teaching children anytime, buddy?
Dude. I can't thank you enough. Now I know how people feel when I make a tech tutorial for them. This was so clear and awesome. Thank you so freaking much.
Wow, I used to find music, movie and all the entertaining stuff exciting on RU-vid but after watching this video not only taught me the lesson but made me realize that even Maths can be interesting. Thank you, Keep the great work up.
You my friend are extremely talented at what you do. It's a nice surprise to find a teacher who keeps a lesson interesting and unique. Thank you so much :)
I really like your way of teaching. You break the puzzle into paces, you simplify it, and then you fix it one by one until the whole picture is drawn. Thank you very much.
I see. I'm an EE major and I have to take a class like that this upcoming semester. I thought that you were taking something like it and this was being discussed in your class.
Supreme Gentleman No I actually just randomly was wondering one day what people meant by standard deviation and youtubed it. I learned it in middle school with the mean median mode stuff but never understood it. and nice dude I'm a mech-e.
Hands down - the BEST way I've seen this taught....I was CLUELESS coming onto this video--I'm DEFINITELY test-ready on this now. I paused the video before you worked out the sample problem, tried it on my own and did it right the first time! Awesome instructor!
dude, this is just perfect!!!!!!!!!!! I watched many many videos, but no one was even close to answer the question marks that I had... it's like you are reading my mind...
Thanks man! I'm an Oral English teacher currently teaching in China and preparing for the GRE and standard deviation has always kicked my butt. I loved your body language crazy enough to keep people's attention and asking the questions that we already have. Perfect teaching style. I'm sure you don't hear it enough (none of us educators do) great job, and great energy. Thank you!!
What an absolute hero. Took me like so long to understand it. About halfway through this video I got it immediatly. Thank you so much. Keep doin' what your doin'
You are the BEST math teacher I have ever seing before. Your videos are now the only source I will reach out for help. Thanks for your passion that it's contentious to everyone who listens to you.
3 years ago I had my statistics exam and I hadn't studied anything. I got up a few hours before the exam and searched you tube and found this video and channel. I got an honour in my exam and I was thrilled. All thanks to this man. Thank you.
I am an MBA graduate student and have never had a professor explain standard deviation as well as this video. THANK YOU for making a complicated problem seem easy.
That was an absolutely brilliant explanation. Thank you so much!!! I've always wondered WHY standard deviations required you to square the figures in the dataset, now I know. Thanks again!
You should be a teacher. You make stuff that I would usualy find boring more enjoyable by your overall attitude and jokes. My teacher had even showed us your videos in class sometimes because he likes them so much.
I got this video to watch and take notes on over the summer, and you've done an amazing job explaining it in full detail. I'm glad this was part of my assignment, and I feel a lot more confident about AP statistics! The school year will be quite different, of course, but videos like this are what will help me get through :)
You are a gem!! Loved it. Will remember for long and you exactly helped me clear the confusion with the formula and how it really came into existence!!!!!
THIS WAS UNREAL. THIS VIDEO is the only video / way of teaching that has me finally understanding SD. Thank you so much! I'll be binging all of your videos now! haha
THANK YOU !! YOU ARE A LIFE SAVER!!! when my professor was explaining this in class it went over my head. I like how you broke everything down and explained what the formula means and what all the symbols mean.. so thank you!!!!
I have a teaching demonstration on Standard Deviation coming up and this has helped a great deal on how to make it understandable. I love your charisma. Thanks so much.
Awesome explanation - after trying to understand this for years, this explanation was what I needed haha the concept will stay in my head for ever lol great job!
You are amazing! I went through like 4-5 different websites before I landed here on you tube and you literally "Nailed" it in my "understanding". It's like a permanent folder being created on my Brain Drive that I would always be able to refer to whenever I see this word "Standard Deviation". It is the first video of yours that I have seen and your abilities and style forced me to subscribe to your channel - I don't even know your name but will get to see it after I am done with the comments here as I so much want to appreciate your efforts and style. Kudos man, you rock and may God bless you!
One small problem which might confuse a lot of people here. Taking the root of the average squared distance from the mean does NOT give you the average distance from the mean. In fact, standard deviation is technically NOT the average distance from the mean (thats where his "sort of" disclaimer kicks in). You can take a look at his example, average distance of {1,2,3,4,5} from the mean is 1.2 but root of the average of squared distance from the mean, root 2, is not 1.2. This still doesn't answer the question, where does the formula come from? Why take the root of the mean of the distance square instead of mean of the positive root of the distance square (which is actually the average distance of the mean).?
+Raymond Foo Thank you for pointing this out. I just realized this last night, and was watching this video hoping to get an answer to the question of why do it this way. Taking the average deviation from the mean seems to make a lot more sense.
+MrNystrom Could you please explain why it is done this way, and why this is more useful than calculating the more intuitive average deviation from the mean? Thanks.
From all the videos I watched with lots of animations and high skills presentation, your video is the only one that gets my full respect ....I just want to say to you ....Thank you very much
Mr. Nystrom, you are still helping people in 2021. I'm in grad school and need to know this for assessment purposes. You saved me from despair. Grateful.
think about another measure of spread.. like the range (high-low). think... what would be higher.. the range of a sample or the range of the population you took it from??? I hope you can see that the population will most likely be higher because a small sample most likely won't have the extreme highs or lows.... we take samples because we are curious about the population.. so if you took a sample's range, you'd know it was probably smaller than the population's.. so you'd guess the population's range was a bit bigger. so you might add a little to the value when you guess the population's range. A similar thing happens with standard deviations.. when we take a sample SD... it tends to be a bit lower than the population's SD... but instead of guessing a bit more... we insert a fudge factor (n-1) in the denominator which adds a bit more automatically.. as the sample gets larger.. the n-1 has less of an impact, as it should, as you'd be picking up more extreme values as n grew. so if you have the population, calculate the SD with just n, because you have all the stuff. if you are using a sample to guess the population's SD, divide by n-1. does that make sense?
That makes sense when you say it like that, but my prof didn't explain it quite like that... Sometimes I swear he's speaking Greek. Lol! Thanks for the explanation.. Wish me luck!
Erin Brooke McDonald Hi Erin, dividing by (n-1) is for sample standard deviation and dividing by (n) is for population standard deviation. I know this is late but oh well :)
Just Paused the video to say that you are awesome, the way you teach..... i have no words to describe every word that comes into my mind is just too small for such an amazing teacher like you.
Honestly my prof could not get this into my head any quicker. I like the style you have with breaking down a formula with definition and explanation of the reason behind it!
Hi. I love your teaching method and thank you for sharing :) I have a question. Can you explain the difference between standard deviation and sample standard deviation. In the second one N become N-1 and I cannot figure out why. :) thank you again. loved your class.
when you are given a problem set and you are to calculate the SD with a "sample" size, you are assuming the population size, so you must include (n-1) as the population number. If you are given the exact number of the population size, there is no estimation here, that is when you utilize just (N). I hope i shed some lil light on this
Eh, waaaaaaait a minute. So the "mean absolute deviation" is the actual average distance to the mean, which in the sample set is 1.2, but the regular standard deviation is sqrt(2), which is 1.41 But you call both values the "average distance to the mean." But 1.2 is not equal to 1.41, so which one is the average distance to the mean? 1.2 seems like the correct answer, so what does 1.41 buy us?
+Andries Liebenberg The first one is the "true average distance to the mean" the standard deviation is "about the average distance to the mean"... We say "the average distance to the mean" because it is about the typical distance to the mean. It gives us something to relate to, (in this case, the concept of average and distance). The standard deviation is a tricky measurement that also accounts for variability within a set. I do not talk about this in introductory lessons as students will miss the point. The two sets 3, 3, 7, 7 and 2, 4, 6, 8 have the same mean, 5, and the same average distance to the mean, 2... Looking at these sets, which do you think has the most variability? I hope you think the second. The standard deviation takes this "variability within" into consideration and it shows up in the calculation because of the squared distances... So the standard deviation of the second set is larger than the first set. Even though they have the same average distance to the mean, the second is more variable....
+Joseph Nystrom t's like when you teach Pi... you don't say its "3.14159..... etc.." The correct way to teach Pi is to say "it's about 3" and use 3 for some calculations of area and circumference.. The fact that Pi is irrational is pretty cool, so using Pi as an introduction to irrational numbers is a good teaching approach, however, using the fact that Pi is irrational to introduce it is a HORRIBLE way to teach Pi. Students get lost in the mystery of irrational numbers and don't ever get to see that Pi is "about 3" ... Pi is simply how many diameters fit around a circle, and how many radii fit around a half circle (hence... radians...).
@@josephnystrom7154 Great video but IMO you should have included this info in the video. It's brief, simple and clearly clarifies what otherwise is a confusing takeaway from the video.
Holy shit! You start with the most intuitive measures and build up to the "accepted" measures. I love you. I always wondered why there so much hate against absolute value when it's much more intuitive
Noel Samkomwa A quick explanation... usually, we take a sample to find out about a population... We may take an average height of 30 random kids at a school to estimate the average height of all of the kids at a school. That would be using the sample mean to make a guess at the population mean.. If we used those same 30 kids' heights to estimate the true population standard deviation, we'd find that our sample standard deviation tends to underestimate the actual population. This underestimate happens over and over... SO... to make a better estimate, we want to make our sample standard deviation a little bigger so it estimates the population standard deviation better... we do that by making the denominator a little smaller, and alas... a slightly different formula..
Where have you been all my math life? I've been dutifully working this formula for weeks without a clue as to why. Now I should be able to remember the formula without constantly referring to my notes. Thank you.
I just started my college Statistics class and was really struggling with this. Thank you for making this so simple to understand. You have a great teaching method.
I don’t know how finding him attractive and pointing it out makes her one or the other. She could have also found this lecture helpful. Also having a libido does not make you a sociologist even if she hates math. Not to mention the fact that she isn’t a representative of all women in the first place. I’m not really upset. I only found this a dumb comment.
I want to thank you for taking a complex topic and making it simple. This was a turning point in my career as an engineer and the discipline of variation analysis. Understanding the essence of std deviation opened up the entire world of process control , GD&T and variation management allowing me to teach others.