Statistics 101: F-ratio Test for Two Equal Variances

Рет қаралды 143,983

Күн бұрын

In this video, we learn how to use the F-ratio and F-distribution to test the assumption that two population variances are equal. We learn the conceptual background and then do an example problem. Oftentimes quality assurance professionals or other analysts wish to test whether or not two population variances are equal. Since sampling error is involved, the ratio of the two sample variances will fall over a range in the F-distribution. The samples will most likely be different, but is the difference significant? Let's find out.
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#statistics #machinelearning

Пікірлер: 147

@Ipherix 8 жыл бұрын

Liked within one minute lol sometimes a supportive message is nice to hear.

@trushadalal8564 9 жыл бұрын

i love the optimism and motivation thrown in with the knowledge haha

@BrandonFoltz 11 жыл бұрын

Hello! My favorite stats book so far is Anderson, Sweeney, and Williams "Statistics for Business and Economics" I LOVE IT.

@eliizabeth7557 3 жыл бұрын

8 years later, you're still saving lives-

@hendelshaarawi7137 2 жыл бұрын

I love the way he starts his videos. He has such an uplifting and kind soul, I genuinely appreciate it.

@jantoinejones 5 жыл бұрын

I was having a hard time conveying F-ratio Test to a student. He informed me this was helpful. I just wanted to say thanks for the great video!

@ruthmatthews724 9 жыл бұрын

This will get me through my exam tomorrow. My lecturer is not very good at explaining things, so this has been a great help. Thank you!

@kuhajeyangunaratnam8652 Жыл бұрын

your lectures are only better source I found so far to understand these concepts. They are done in a very well detailed manner for understanding below par person like me. Thanks a lot Brandon.

@MsAnnaChristine 9 жыл бұрын

This is beyond great. I love how you are able to turn something this complicated, into something so simple. Great with references to WHAT you can actually use these things for, instead of merely knowing HOW you can calculate it. A big thumbs up from Denmark.

@kikikarei9210 Жыл бұрын

Great. Thank you for the sacrifice in making the vedio.

@HeRuruAhau 10 жыл бұрын

Concise. And I really appreciated the vote of confidence at the beginning and the end. Great positivity. Thanks, Brandon :)

@BrandonFoltz 11 жыл бұрын

Hello! Thank you for watching. Actually all of my videos are organized into sequential topics and then within each playlist also on my channel page. KZfaq does a terrible job letting you know what you are watching is part of an overall playlist. Click "Videos" under my name and then change "Uploads" to "Playlists" Let me know if you cannot locate them. Best, B.

@andreaanderson9870 5 жыл бұрын

Thank you for the positivity and the slow, deliberate explanations of each step. Your videos make me feel like I can actually get through my statistics class.

@yogeshpagadala3225 5 жыл бұрын

Complex topics are explained in a simple and understandable way . Thanks a lot

@lupiris11 8 жыл бұрын

Thank you for the motivational talk in the beginning, def needed it.

@paulkortman2806 6 жыл бұрын

One of your best presentations. Not only understandable, but showing the app and especially the Excel formula was a blessing. Often, statistics ends up becoming more of an advance Excel course than a statistics course. Loved the extra help!

@markneumann381 8 ай бұрын

Thank you Brandon so much. You are an outstanding teacher. I appreciate the work you have done: guiding people along their journey in the world of statistics and data analyses. I also appreciate your having recognized the work being done by Josh over at Stat Quest. Both of you are my You Tube gurus for statistics. Your sincerity and conviction as a teacher are so wonderfully witnessed in these teaching courses. Again 'danyabad' (thank you)!

@salmanshafqat8180 4 жыл бұрын

Great video. You are a natural teacher.

@blessingmlandeli2170 3 жыл бұрын

Your channel has been my lifeline during my masters. Thank you so much for explaining things clearly.

@BrandonFoltz 3 жыл бұрын

Happy to help! But your lifeline can be found in the mirror. You came here and clicked. And that made all the difference.

@armandosandoval8730 5 жыл бұрын

I never comment but your explanations are so helpful that I just have to say thank you and please keep these videos up! Your motivation very necessary in finals season thanks thanks thanks!!!

@grounduplearning4990 9 жыл бұрын

This is the best video I've seen on the F-test and F-distribution! It's done so well. Thank-you for this

@crisphighfives 3 жыл бұрын

I appreciate the clarity of explanation. Thank you, Brandon.

@dcrow2009 6 жыл бұрын

All your lectures are awesome. There is no way to describe how much I and others benefit from your approach. You maybe an outlier but we should learn from that too.

@HabibKhan-wd1rn 10 жыл бұрын

Excellent Sir, I am thankful for these videos, they really help out. I am a business student, although at PhD level but not very good at statistics. I am able to build these concepts through these videos. Thank you again sir for uploading those videos. Humble Regards

@arrelite 8 жыл бұрын

a friend linked me this thing. After watching these videos I feel much safer in the course Im following. These videos quite literally created a bridge between me failing and passing my course. Thank you so much!!

@JuSophieRene 6 жыл бұрын

Omg, thank you for saving me before exam week!!! You make so much sense!

@janel6803 3 жыл бұрын

Thank you. you explain a concept troubled me for a long time

@genemaker4976 9 жыл бұрын

That was a great video Brandon. Very clear, well paced (for a beginner) and informative. I have liked, subscribed and passed your channel on to other students here in sunny Australia.

@Partiprincezz 9 жыл бұрын

Thank you for making these videos so clear and precise. As a student learning Statistics for the first time, I found these very helpful and simple to understand. You my friend, are awesome. Ps: I love your encouraging messages at the start and end, it really helped motivate me to keep trying. :)

@ishaagrawal5869 6 жыл бұрын

Thank you sir.. I was actually confused a lot before in my class with regard to the concept but you have made f-test my favourite topic. Thank you again...😊

@oliviahedlund6994 6 жыл бұрын

I love your videos!! They are extremely educational. Thank you for making me understand this 😊👌🏽

@reemahmed6822 8 жыл бұрын

Your videos saved my life! Thank you so much for your much appreciated effort! :)

@sunilkakarla1954 8 жыл бұрын

Best instructor ever! Loved it..

@fort5sbc 9 жыл бұрын

Brandon, you are a great and encouraging teacher. Thank you!

@glennsmith6762 9 жыл бұрын

Brandon, you make statistics so easy to understand!!!

@Anran07 8 жыл бұрын

thanks so much for these videos. explained things in a concise and precise way. makes learning that much more efficient.

@wyj4549 9 жыл бұрын

Thank you for the great lecture. It helps me a lot indeed

@xomegsxo 9 жыл бұрын

Thank you so much for your videos!!! They are helping me so much in my statistics class... Your videos really help me to have a clear understanding of all the concepts

@camalot02 8 жыл бұрын

Thank you!!! this is so helpful! I am taking Graduate Research Methods, and this was so helpful!

@psas09 11 жыл бұрын

Easier than I expected it to be. Thank you very much.

@simplitia 8 жыл бұрын

thanks; perfect balance of what to put in and what to take out. I'm especially grateful that you left the the whole chi-square thingy ;)

@Bittaneel 8 жыл бұрын

thanx alot for helpin' us to better understanding of F ratio testin'. realy thank you from my heart

@anjanisingh4526 5 жыл бұрын

I love your videos , thank you so much for wanting to help people !! you are awesome !!!

@sjaxn314159 9 жыл бұрын

Thank you so much for doing all this work! I wish my prof was as helpful as you are!

@krissgross2335 10 жыл бұрын

I really wish I had found this sooner. Thank you for posting these videos.

@kyongranpae5283 4 жыл бұрын

Thank you, your video has been helping all along

@natiajohannesen5357 9 жыл бұрын

You are really explaining great. Thank you!

@Nukerz999 10 жыл бұрын

thank you for your videos before I found them I was completely lost in my stats class could not follow along with discussion or class work at all the teachers explanations went right over my head but your videos saved me. thank you very much

@elliestewart125 6 жыл бұрын

Thank you so much, your videos are extremely helpful !

@meghansmith2010 10 жыл бұрын

All your videos have been so helpful

@rody1934 7 жыл бұрын

Thats good . Very clear and straight forward

@isoboy2125 7 жыл бұрын

I'm a smart, talented, amazing person, and I'll never let anyone tell me differently... *trance* Thanks for the wonderfully done video!

@mariamtashkandi1982 10 жыл бұрын

Thank you so much for your videos they were really useful and you have a great way in explaining things!

@lp7881 4 жыл бұрын

you saved my life !!! i have a statistics presentation monday !! wish me luck :)

@neurorn477 8 жыл бұрын

Thanks so much for the pace and clarity. Pretty cool how global your fan club is! Names from around the world. This grateful grad student is saying "thanks" from Montana.

@jagathfernando4682 9 жыл бұрын

Great Video. Very useful. Thanks a billion. Explanation is clear and very simple.

@shrikantprabhu799 8 жыл бұрын

Nice and simple introduction to F distribution ! Keep up the Good work Professor Brandon ! Thanks ...

@selinavu9344 3 жыл бұрын

The first minute of your video

@umarlatiff9595 6 жыл бұрын

Love the pep talk

@jordancardenas2422 2 жыл бұрын

Thank you so much for this video, it helped so much to breakdown what a F-ratio is. I have been struggling in statistics so this helped a lot

@SurinderSingh-mr9ey 8 жыл бұрын

Ultimate explanation.....thank you for such great lecture and motivation...

@parthgunjal7073 5 жыл бұрын

Hey, Keep doing the good work! You are really good at it...

@angryfieldmouse 11 жыл бұрын

Thanks! It was just the tutorial I needed!

@mjitape2083 11 жыл бұрын

Thanks man...great presentation and great explanation...Salute from South Africa

@stevencampasjr.2840 7 жыл бұрын

Great video. You have an excellent way of explaining a difficult topic. SC

@malvis8737 2 жыл бұрын

I like the motivation part , thank you .

@naveenbhatnagar5854 9 жыл бұрын

Both the content and explanation of these concepts seems very easy to understand.in your videos.

@sarasadeghi3608 5 ай бұрын

Thank you so much! very nice explained

@xiangqiwang5944 8 жыл бұрын

Thank you so much sir! You completely saved me

@kirakiralovely2014 7 жыл бұрын

Thank you! This was super helpful!

@jve5483 8 жыл бұрын

Thank you for making this video!

@ireneashamoses4209 4 жыл бұрын

Excellent explanation!! 😊💗👍👍

@JeFFiNat0R 4 жыл бұрын

you are so good! thank you!

@NickGlasgow 9 жыл бұрын

Excellent Tutorial

@TheBirdBrothers 9 жыл бұрын

nice and clear thanks fellow

@dreamcolouredsky6166 5 жыл бұрын

What a reassuring and nice intro. :)

@vikas1905 10 жыл бұрын

Nice explanation.. Thanks a lot

@arifulsohag1782 7 жыл бұрын

THANKS, IT WAS HELPFUL.

@myrss8832 3 жыл бұрын

that outro hit hard...... thank you

@preeyank5 7 жыл бұрын

Thanks man!! you rock!!

@TallminJ 8 жыл бұрын

Great video mayne

@bathama.k.7759 6 жыл бұрын

good explanation

@ricans4everus2332 10 жыл бұрын

thanks for ur assistance

@aliakbarianmajid 11 жыл бұрын

well explained.

@mundaJoel 8 жыл бұрын

thank you very much

@eskeybee 10 жыл бұрын

thank you so much!!

@yolandamudukuti9257 Жыл бұрын

Thank you thank you thank you thank you thank you!!!!

@frankvangool1716 9 жыл бұрын

Great and very usefull video's!

@BrandonFoltz 9 жыл бұрын

Frank van Gool Thank you! :)

@harshalshinde227 8 жыл бұрын

goodness of fit test shud be first in the playlist and then afterwards chi test and F test.

@harshalshinde227 8 жыл бұрын

Can u make an abridged video or a comprehensive video, where u can cover situation in which we can use a particular video. Also, plz make an video, emphasizing statistics in medical field - 1] How to read the result of study 2] How to determine that the study is plausible and not just manipulated via p value 3] Effects of power[ a dedicated video] 4] Cohen's d, this thing popped up on many sites 5] Biostatistical concept like odds ratio, relative risk 6] How to conduct studies and hence write thesis U are just awesome. The amount of Lynda certification u got is just awesome and ur videos speaks for them. I wish u a very beautiful career and happy life! Keep it coming.

@pablosanchez8179 Жыл бұрын

excelente!!!

@tusharmodi9883 8 жыл бұрын

Hi Brandon, I have basics understanding of Stats concepts. Can you please help me with the complete curricula or syllabus to get a complete statistical knowledge? I didn't find any such resources useful with the complete flow of where to start but your videos has helped me a lot. Thanks Keep it up.. have a great day ahead.

@healthfreak5438 8 жыл бұрын

Brandon, many thanks for putting this series on youtube. Can anyone tell why can't we find F-ratio for sample means similar to what we did for variances? why do we have to compare them using t-test or z-test?

@MsAndisheh 6 жыл бұрын

Thank you Brandon! No really!!! Thank YOU! :)

@NikkiThapa 9 жыл бұрын

thank you some much..:)

@safaaal-wajidi4606 7 жыл бұрын

Thanks.

@aboogen 8 жыл бұрын

thanks brandon

@nishantjain7775 10 жыл бұрын

thank u sir

@dr024 2 жыл бұрын

In 6:30 it was stated that we are not comparing sample variance with hypothesized variance… BUT IN REALITY, WE DO SOMEHOW. We have population variance1 and population variance2 in the F statistic. because F statisitc is actually ((sample variance1)/(population variance1))/((sample variance2)/(population variance2)). So we may not be “comparing” sample variance wih population (hypothesized) variance but we are “comparing” sample variance RATIO with the population variance RATIO. That is similar to the test of 2 means where we compare the sample mean DIFF with the population mean DIFF.

@kane3525 7 жыл бұрын

Very clear video. Love it. But in some contexts they still use 2 tailed test. Its not like u said in 13:07 and this does change the result. So what should I do. upper right tailed or 2 tailed. Thank you

@sheafsmash142 2 жыл бұрын

Nice videos! By the way, do you have a pdf about the topics of your videos? I would like to skip the first 10 playlists but reading those topics. Thanks in advance 😀