How To... Calculate Pooled Variance in Excel 2013
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- Опубликовано: 11 сен 2024
- Pooled variance is used in Student's t-Test for comparing means where equal variance is assumed. Learn how to manually calculate this statistic using a simple example.
7 Years later and you are still helping students, thank you so much!
Your voice and accent is beautiful Eugene
Thanks you helped me a lot
Thank You Sir very helpful video.
Hello,
what about calculating S_pooled using the formula: S_pooled= sqrt( Variance_within+Variance_between). Which is the most meaningfull this formula or the formula in the video ?(PS: I think we must include the hypothesis in the formula that I've mentioned which is the normal distribution of observations) .
Thank you!
In the Book of Humongous Statistical Problems, the pooled variance is calculated without the complex square root. So the equation starts with Sp and not S2p. Any thoughts? I might fail this question then?
Eugene O'Loughlin Your "How To... Embed a video in Powerpoint 2013" is outdated I tried using old embed code but the option isn't there.
Please respond as soon as you can. Thanks.
Thank you Sir
Hey Eugene, How would you calculate the variance for a particular day? I.e Use xxx stock price data over period 03/01/2005-31/12/2014, estimate the variance
for the date 01/01/2015.
Hi +Sebastian Maxwell - I'm guessing your question is not about pooled variance (which is the variance of two samples combined)?
Variance is a measure of central tendency around the mean of a sample. You have nine years of data for xxx stock. Unless there are dramatic changes in a stock's price, variance will not change much as new values are added every day - in order to calculate variance for your sample you would have to re-calculate variance on 01/01/2015.
However, I'm not sure that it is variance that you want - it seems to me that you are looking to make a prediction, and variance is not normally used for this. Have you thought of using moving averages?
I have a series of videos on how to calculate moving averages which are used in prediction. Go to my RUclips Channel (ruclips.net/user/eoloughlin) and search for "average" - this will display a short list of videos which might be more suitable.
Dr E.
Hi Sir, lets say I have a criteria, and in that criteria, I have no.s, 1, 2, and 3 with 30 equal respondents. Should I still put 30 in n1 & n2, and average variance of that 1, 2, 3?
+Jun Garcia
Are you doing this for a t test to compare two means?
Dr E.
Eugene O'Loughlin Yes, sir. I think I already got the correct value. Thank you for this video, its really really helpful. Good day!
Dear sir if you provide me it's Excel sheet .. that is your pleasures