Standard Error of the Mean

This statistics video tutorial provides a basic introduction into how to calculate the standard error of the mean from the sample standard deviation as well as the population standard deviation.

Introduction to Probability:

Central Limit Theorem:

Standard Error of The Mean:

_____________________________________
Confidence Intervals & Margin of Error:

Find The Z-Score Given Confidence Interval:

How To Calculate The Sample Size:

Student's T-Distribution:

Confidence Interval-Population Proportion:

Chebyshev's Theorem:

_____________________________________
Hypothesis Testing - Null & Alternative:

Type I and Type II Errors:

One Tailed and Two Tailed Tests:

Test Static For Means & Pop Proportions:

Hypothesis Testing Problems:

____________________________________
Final Exams and Video Playlists:

Full-Length Videos and Worksheets:

[travisdean]

You got me through undergrad, now I'm watching your videos for medical school 6 years later. Love you.

[hamida.]

How do you know every thing from physics to biology, chemistry, math in detail. I am speechless.

[JamesJon]

If anyone else was super confused about "n-1", apparently, it's called "bessel's corrections" and it's the due to the difference between a full population's standard deviation and a sample of the population. If it's the full population you use "n" and if it's a sample, you use "n-1".

[suzannechadwick]

I've checked out so many and you are by far the best. I truly understand after I watch the videos. Not like others where I'm just as confused as when I began. Thx

[ouranos]

I don't actually have anything to comment, I just appreciate how well you explain things in your videos, and I've heard that commenting on videos helps

[ArYan-fxty]

my favourite guy for everything, beside the khan academy guy

[mokotb]

In the second example, the 9th minute exactly, you said the relation is that when you increase the "n" by a certain factor, the standard deviation of the sample decrease by the half of this factor. Actually the standard deviation decreases by the square root of this factor not the half, as if you try any number rather than 4 it will explain my words.
Thanks

[shadiaaborakhes]

Thanks allot u r better than any lecturer at the university. Love u fir that ❤️❤️❤️❤️❤️

[justinfrank]

Physics, chemistry, Maths, geology, biology. I'm still wondering how this guy managed to know everything 🎉🎉

[eliaswondamlakzeleke]

dear our teacher thank you to give us these great tutor. I ame from ethiopia

[veerakanneboina]

1) I was given with 4 values, which are considered population. Then I have made possible samples of size 2, I got total 6 samples.
Now I calculated mean of these 6 samples(m1, m2, m3, m4, m5, n5).
Now I was asked to find the sample error of the means how to calculate it. Can you explain it clearly

2)And are there both population standard error and sample standard error
3)And i can't get where to use sample standard deviation and population standard deviation.

[ramlanzaderas]

Hello Can I ask Why did you come up with 3.114 I can't Get it in my Equation

[nguyenmsg]

Thank you man, you just helped me pass my AP bio exam

[brunnobenatti]

Just found your channel and I'm in deep love with it. Thank you very much for your work.

[aracupcupin]

How did you get the 3.114? I don't know how to put the sum of variance in the calculator to get the 3.114

[fatimaothman]

If my sample size is small, should I do a normality test and why?

[VIJAYKUMAR-vygf]

Excellent explanation. I appreciate your teaching skills

[richardkale]

Please help with this question: A survey of 500 adults showed that 240 of them drank alcohol daily. Calculate
standard error for the adult population that drink alcohol daily and also
construct the 95% confidence level.

[gauridubey]

Just loved it, I was trying so hard to learn this but you made it so simple for me.Thank you so much.

[alexgoldberg]

Isn’t it that when you have something with a negative in parenthesis and square root it, it is always positive. For example (-0.8)^2 would be 0.64, but -0.8^2 would be -0.64. In they first problem the answer was as if the numbers didn’t have parenthesis around them. I’m the proper equation should you put parenthesis around the numbers when squaring them of not?