How to Calculate Variance and Standard Deviation

Learn how to Calculate Variance and Standard Deviation for both a population and a sample data set, along with a worked example of the sample variance and sample standard deviation.

0:50 – Introducing the Equations for the Standard Deviation and Variance for both Populations and Samples

2:33 –Example for Sample Standard Deviation and Variance

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[eventhorizon]

You are a life saver. I have a huge test tomorrow and I could not for the life of me figure out even what each of the symbols meant from my teachers notes. thank you dude

[capnroberts]

im doing L1 CFA and this finally made the quant section click for me. thank you so much matey :)

[garima]

Hi Andy I really like your sessions and its building my confidence to face my CQE exam. Thank you so much!

[danieltesfay]

This is great video!!! Standard Deviation and Variance are the key elements in Statistics. Knowing or understanding these concepts would help one to deal or handling big data samples easily. Thanks for sharing this with us!!!

[salaheldin]

Brilliant. Thank you so much for the proper and easy way to simplify the calculation of variance and standard deviation in both population and samples.

[natekemp]

You are more helpful than my college instructor. Thank you!!!

[haroldsimpson]

Excellent Andy I know this but I enjoyed how you taught it as this is how I taught suppliers employees how this works by pen.

There are calculator that do this for us, but to know what to do is priceless.

[luisalmanza]

This video showed me a lot!! Thanks for taking the time to make these its been a great resource

[edwinscox]

Super clear. Easy to follow. Thank you!

[mahgoubhamid]

Thank you very much for sharing this vedio 🌹

[hopebaran]

I didn't understand the square root of 94? can you explain how calculated that number? Thank you
I am a science student so these are all new to me :)

[ziadabderrahmanesalem]

Thank you very much for this video.
I would like yo ask why we devide by N-1 and not N when calculating s for samples?

[pwrmx]

You should explain why the values are squared.

[phunglethuy]

Anyone helps me with this please. 
Suppose a sample of n = 74 observations was taken and the sample variance was calculated to be 1011.24. What is the sample standard deviation? Where relevant, round your answer to three decimal places.
To obtain standard deviation, we just need to take the square root of the variance. Does n = 74 have anything to do with the calculation of standard deviation?

[EdwardThen]

Hi Andy.
Thanks for sharing.
But just curious, is scientific calculator not allowed in US's CQE exam? If we key in all the figures in a scientific calculator, then we can get the variance in less than a minute.

[ratnasekharchatragadda]

Hello Andy, What is difference between standard deviation overall and within, How this was calculated from sample data. Minitab is showing the both value when we perform analysis. Can you please give some clarification on this