Type formula in Excel format

Hi Experts,

I'm trying to determine the number of audit samples required in a call center with the following parameters:

Transaction/Volume: 110,000
No. of Agents (population): 100
Confidence level: 95%

I found this formula onlineFormula.jpg.

I've attached a sample workbook and i followed the formula but i can't match the answer in the website.Book1.xlsx

Based from additional research N is the population or in this case the # of agents


Please help.

Thank you,

Which of your values is e and which is z? What is N?

What have you tried so far?

With no idea of expcted result, I tried this:

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AliGW on MS365 Beta Channel (Windows 11) 64 bit

	A	B	C
1	110000	N
2	100	p	113276.3
3	98%	z
4	0.05	e

Sheet: Sheet1

I also trying this. Which i assume.

Formula:

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Formula:

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File Attach.

thank you for the help Experts. The result in the website is 285 based on the following parameters:

Monthly Call Volume: 110,000
No. of Agents (population): 100
Confidence level: 95%

I've included the link to the website in the sample workbook Book1.xlsx. I'm trying to understand how they came with 285.

Sorry - I have no idea about the calculations you've already tried - I just don't understand them or your logic. I'm out.

That formula just returns whatever value you put in for N.

Do you mean the formula in post #1 or one of the attempts to create it in Excel?

Both. (the formula in the last workbook is a straight recreation of the one in the picture).

It appears to me to be an error on the website's part in defining p or in describing how p goes into the formula or something.

Analyzing the function, I see, as rorya began to suggest, a horizontal asymptote at y=N. As p approaches +/-infinity, y approaches N from the positive side. I also note to vertical asymptotes at denominator=0 (p~-0.06 and p~1.06. Exact values can be found by solving the quadratic equation).

I note that I can use Solver/goal seek to find that y=285 when p~1.092 (or -0.092), but I don't see how to get either of those values from 110000 calls and 100 agents.

I dug into the source code for your calculator's website. I see that they are calculating sample size as:

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or what looks like numerator=z^2*0.5*(1-0.5)/e^2, denominator =1+(numerator-1)/(callvolume/agents). If I put 1100 into B3 and 0.5 into B6 of your spreadsheet, then your spreadsheet will calculate 285 for the sample size. It appears that they did a very poor job of describing their calculation scheme.