Degrees of Freedom and Effect Sizes: Crash Course Statistics #28

Today we're going to talk about degrees of freedom - which are the number of independent pieces of information that make up our models. More degrees of freedom typically mean more concrete results. But something that is statistically significant isn't always practically significant. And to measure that, we'll introduce another new concept - effect size.

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[libertarianPinoy]

I hope you discuss ANOVA in the future. First time I understood degrees of freedom.

Also it would be really cool if crash course website had some work sheet excercises for these topics.

[doodelay]

The explanation of degrees of freedom in the credit card thief example was a stroke of genius

[emilyclarke]

I have an exam on statistics (especially multiple regression) in two days and this just helped so much!

[justynaizabela]

This is an awesome series! Explains so much! I am surprised it's not more popular because this knowledge is much in demand on the job market...

[madanverma]

Best explanation of the topic. Bees example is a killer one and also the Credit Card example. I wish we had such brilliant teachers at grass root level, so that maths does not feel boring and hard. Thank you entire team of Crash course.

[johannachesshir]

That Mean Thief bit would make a great children's show idea

[revolutionarydefeatism]

Actually, everybody's credit card number HAS an effect on other's, because it excludes that number!

[jamiekwon]

Brilliant example for degrees of freedom. Thanks a lot.

[JackDraak]

CrashCourse rocks! Thanks for the uploads!

[soulfrench]

@10:17 Any person knows why the denominator is (s1^2+s2^2)/2, different from the pooled variance from the two-sample t-test? Why is the variation divided only by 2? Is it just the case that Effect size use the different denominator than the two-sample t-test?

[AntKPro]

That bee example is hard to understand. Where 5420 comes from? Why is there 100 under the square, but they tell about 99?

[francoislacombe]

I miss the little bamboo plant. I hope nothing bad happened to it. 😟

[VashdaCrash]

Ok, first half of the video I didn't get anything (as always), but when they started to talk about how practical significance is just as important as statistical significance and stuff, then I went: "Oh, so that's what you're talking about!" xD

[JoeMaza]

I saw your plush of BOO the dog. RIP Boo.

[dr.honeypremendra]

Appreciations for a very nice initiative by introducing dialogue box which will help a lot in depicting what you all actually want to convey...many times..

[donovan]

Can you teach us about Artillery Only?

[libertarianPinoy]

This is awesome. Hope you guys do regression and forecasting too.

Brushing up on my econ subjects since I have never used them.

[hochinghui]

LOL, I have statistics quiz in hours and here I am.

[Megastash]

could you guys do one about mono hybrid inheritance

[JCResDoc]

3:04 you will never know where you are on any distribution until degrees of freedom are removed - which they never are (n-1)