generating lognormal and powerlaw distributions in excel

Hi everyone,

First time poster, but long time lurker. I am working on a project that requires that I generate a series of randomly generated distributions. I have done a normal distribution with a mean of 45 and a SD of 3.33 by using the following code:
=(NORM.INV(RAND(),45,3.33)

I am now trying to do a lognormal distribution. When I do simply =lognorm.inv(45, 3.33), I get some terrifically large numbers that are functionally unusable. I suspect that I am not scaling my mean and SD correctly. Does anyone have any insights into how I could generate this distribution correctly? Since the distribution needs to be skewed by definition, I assume that the SD needs to change, but I am not quite sure.

Lastly, I am hoping to generate a power law distribution as well. From what I know, Excel does not have a built in function to do this. Does anyone know the formula to obtain such a distribution?

Thanks for your help here.

Bye,

H

I think you are missing one crucial argument in Lognorm.inv function.

Syntax =Lognorm.inv(probablility, mean, standard_dev)
All 3 arguments/parameters are required.
So looks like you are missing probability.

Read below for details.
https://support.office.com/en-us/art...1-E151B2D4F600

Ok, that is good to know. Thanks, CK76. I suppose my follow on question would be how do I determine the probably associated with the log-normal distribution. That part eludes me.

Thanks again for the link, CK76.