
1. Re: How to Calculate Confidence Level, Standard Deviation, Weighted Response, Pvalue Dynamically in Tableau
Don Wise Nov 26, 2018 12:37 PM (in response to Mahesh Gujar)Hello Mahesh,
I was only able to get you partially there. Had to stop at the Standard Deviation calculation as I wasn't arriving at nearly the same values that MSExcel is producing, even when mimicking the calculation out of Excel. Perhaps someone else will also see this post and see something that I don't...I tried a number of different scenarios and table calcs and didn't come close to those that you need...sorry! I was able to get you Weighted Response & Conversion Lift; both of which, required some additional table calc settings (you should look at them to see how they're set).
Regardless, attached is a 2018.3 workbook and below are some sample screenshots to help you (or others along):
Conversion Lift:
Weighted Response:
This is the STDEV calculation I did to mimic the MSExcel version, with unequal results:
This version of STDEV calculation using Tableau Function matches that of several calculators:

Dynamic Values.twbx 18.3 KB


2. Re: How to Calculate Confidence Level, Standard Deviation, Weighted Response, Pvalue Dynamically in Tableau
Mahesh Gujar Nov 26, 2018 11:09 PM (in response to Don Wise)Thank you so much Don Wise. Really appreciate your help.
This is a ray of light for me!!
With current value of Standard Deviation, could you please show me a way to calculate pvalue and confidence level.
I will work on Standard Deviation value till then, and will let you know if I come across anything.
Thanks a ton, Don.

3. Re: How to Calculate Confidence Level, Standard Deviation, Weighted Response, Pvalue Dynamically in Tableau
Don Wise Nov 27, 2018 8:57 AM (in response to Mahesh Gujar)Hello Mahesh,
Please see newly attached 2018.3 workbook. I've added in a PValue and Confidence Level, however, not sure they're correct as Confidence Level relies on PValue.
PValue is calculated based off of Tableau's ZScore calculation Calculate Zscores  Tableau so please read that thread for some understanding.
The PValue calculation in your Excel file is using TDIST (Student Distribution Score); which returns the Percentage Points (probability) for the Student tdistribution where a numeric value is a calculated value of t for which the Percentage Points are to be computed. The tdistribution is used in the hypothesis testing of small sample data sets. In Tableau, TDIST doesn't exist in terms of an equal equivalent.
However, I did locate the following thread where a PValue was calculated using Tableau's ZScore methodology: To achieve T.Dist() function of Excel in Tableau to get the pvalue of a TTest So, hopefully you're getting the values you need. Not sure due to the amount of data involved here which is very small. Hopefully your real data set is a larger set of data? The Confidence Level is fairly simple after that which is: 1[PValue] formatted as percentage, per your Excel file.
Again, my results don't match yours whatsoever; of which, goes back to the original method in the Excel worksheet for Standard Deviation and how that's being calculated. I'm using Tableau's results for Standard Deviation, which is why my numbers are different from yours. Each of your results from LefttoRight are contingent upon each other until the final Confidence Level value.
Hope it helps! Thx, Don

Dynamic Values.twbx 18.7 KB
