Statistics 101: Sample Proportions

Рет қаралды 45,070

Күн бұрын

In this Statistics 101 video, we learn about the fundamentals of sample proportions. To support the channel and signup for your FREE trial to The Great Courses Plus visit here: ow.ly/doxR30njfZy
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Пікірлер: 52

@j.anderson6503 5 жыл бұрын

I've been using your videos to refresh my basic stats for my final dissertation defense in biostatistics. Thank you for these videos, they are fantastic!

@ariacube07 5 жыл бұрын

i am binge-watching your videos for my statistics exam. wish me luck. and thank you for making such helpful and understandable statistics materials.

@rbewoor 5 жыл бұрын

Brandon the way you present and explain these concepts, you are truly gifted! Your own clarity of concepts and the effort put in to make these dense concepts clear to the viewer are very obvious. Kudos sir!

@BrandonFoltz 5 жыл бұрын

Thank you! :)

@kailashkarwa221 5 жыл бұрын

Thanks for simplifying stats.Keep enlightening us.

@Shreyash709 5 жыл бұрын

It's a really great video to understand. I believe lots of effort and knowledge is required to create such a type of tutorial. really thanks

@prabhudaskamath1353 4 жыл бұрын

Thank you Brandon. You are the best

@kashishjain78 4 жыл бұрын

11:18 how we substitute the value of population proportion p with sample proportion p-bar which is 0.567

@abdullahbabor4876 4 жыл бұрын

I am confused too!!

@yonasgetachew3361 4 жыл бұрын

thank you kindly, this was really helpful...

@adesomojujames4095 9 ай бұрын

thank you so much B, it is goign a long way in my python work

@jaweriaraza1463 Жыл бұрын

Best channel i found... best videos and playlist

@BrandonFoltz Жыл бұрын

Glad you enjoy it!

@evanssabawo2499 2 жыл бұрын

Brandon you are explaining the concepts very clearly

@cococnk388 Жыл бұрын

You are the best sir

@MuhammedShiharMZaid 5 жыл бұрын

Thank you boss!

@AJ-et3vf 2 жыл бұрын

awesome video! THank you!

@manzoorwanigeo2335 5 жыл бұрын

Very nice.. Thanks sir

@vincenzo4259 2 жыл бұрын

Thanks

@ericadhikari1598 11 ай бұрын

loved it

@fineschaumburg5211 5 жыл бұрын

Dear Brandon, many thanks for all your fantastic videos! One question: in minute 11.01, when calculating the standard error, the formula demands to put in a value for "p" (population proportion), but instead you fill in the value 0.567, which was previously calculated as a value for "p bar" (sample proportion). Why is that so? Do you consider that "p" and "p-bar" are the same?

@vulnerablerummy 5 жыл бұрын

i'm gonna assume they're the same for now since he only takes one sample proportion (one test to find E(p-bar)), whereas in previous videos on sample means, Mr. Brandon takes multiple samples (9 test to find E(x-bar)). add a grain of salt to that since this is only my hypothesis

@tallajayakumar5277 3 жыл бұрын

Hello, I've got the same doubt after rewatching the video I've got clarity. It's because population proportion is the expected value of the sample proportions E(p(bar)) = P. And E(p(bar)) is the average of the sample proportions that we take. So here E(p(bar)) = P = avg(all(p(bar))). there is only one p(bar). so P = p(bar)

@kinjalvora3352 3 жыл бұрын

Hi Brandon, so there are multiple ways of calculating Z-scores. If the sample is regular Z = x-xbar / standard deviation if it is a sampling distribution: Z = xbar - E(xbar) / (standard_deviation / sqrt(n)) if it is a sampling proportion: Z = pbar-E(pbar)/sqrt(p(1-p)/n) Can someone please explain when to use which one? what is the difference between sampling distribution and sampling proportion? Also how does one come with the formula for standard deviation as sqrt(p(1-p)/n)

@tunahangumuskaya5356 5 жыл бұрын

Hi Brandon, You can create your sampling distribution with only one sample because the rule of the approximation to normal is fine for this example. Am I right? or Can you create sampling distribution with only one sample in general? Thank you in advance.

@rbmian 5 жыл бұрын

You literally saved my educational career, thank you.

@Annie-star-Light 5 жыл бұрын

14:38 the mean(at z=0) that was used, is that population proportion P ? I am a bit confused.. can some one help me with this?

@robertasalatioan 4 жыл бұрын

Best

@kashishjain78 4 жыл бұрын

11:18, In calculating the standard error of proportion we need population proportion then why you are putting value of sample proportion

@adeyemiadeyanju2247 Жыл бұрын

Hi Brandon, thanks for this wonderful video but I'm a little confused in 10:19, i thought the formula for z-score is "z = (x-μ)/σ," are there different formulas in calculating z-score for standard error for mean and standard error for proportion ?

@mohdibrahim2173 9 ай бұрын

It's sampling distribution of sampling proportion standard error of mean is as standard deviation of sampling distribution. Maybe that is the reason of using standard error instead of standard deviation of population or sample

@mohdibrahim2173 9 ай бұрын

Standard error of mean and standard deviations of sampling distribution are same

@manzoorwanigeo2335 5 жыл бұрын

How can we get a relationship when independent variable is qualitative in nature and dependent variable is in quantative

@BrandonFoltz 5 жыл бұрын

Hello! A few ways, but easiest may be to set up dummy variables for the IVs and then use regression.

@swethakulkarni3563 4 жыл бұрын

timestamp 16:43: Why 0.55 is on the left side of 0, since it is a positive number, can’t it be between 0 and 0.6572 ?

@StocksKingPRO 5 жыл бұрын

Sorry, what are these tests you are running at 11:30 ? Before you said n/N and its relationship to 5%. Now you are saying stuff about np and n(1-p) and their relationship to 5%. Whats going on?

@wackojacko1997 Жыл бұрын

@BrandonFoltz -- I have the same question as the OP above. I assume that I'll find out why you are using 5 to determine if you can use the normal distribution in a prior video, but when I see it here in the video, I have no idea where it comes from. The 5% that Ethan mentions I think is just a test of significance and unrelated to the 5 mentioned at 11:30 (I think?).