# Chi-square distribution introduction | Probability and Statistics | Khan Academy

Chi-Square Distribution Introduction

Watch the next lesson: https://www.khanacademy.org/math/probability/statistics-inferential/chi-square/v/pearson-s-chi-square-test-goodness-of-fit?utm_source=YT&utm_medium=Desc&utm_campaign=ProbabilityandStatistics

Missed the previous lesson?

https://www.khanacademy.org/math/probability/statistics-inferential/hypothesis-testing-two-samples/v/hypothesis-test-comparing-population-proportions?utm_source=YT&utm_medium=Desc&utm_campaign=ProbabilityandStatistics

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Thanks! Never had a class for this subject but now I understand it all!

How does this distribution approach standard normal distribution (mean = 0) as df increases if the mean is increasing? Isn't it just approaching a normal distribution (not standard normal)?

You forgot to normalize the new chi-squared distributions. You need to make sure the multiple integral ("volume") under the multivariate probability distribution is equal to 1.

Good

Actually this introduction vid seems to be the only of your chi-square vids I´m having a hard time to understand haha. I guess I shouldn´t have skipped the basics.

i can pass my exams because of you..thank you so much!

it's useful, thanks so much.

This guy's classroom probably has more A's than an Energizer factory.

~Reus Vult Ave Sumia, Pegasus Breeder and Root Beer Connoisseur

Can the chi-squared random vars follow any type of identically distributed set of random vars?

You're the best!

the normal distribution is actually "standard normal" with (0,1) AND the degrees of freedom is N-1. NOT 1. If your gonna post stats stuff get it right