Lognormal distribution

[Carl Betterton <carlb uga edu>]

I agree, and believe the Gnumeric function RANDLOGNORM does exactly what 
the Excel function LOGINV does, if a random probability is used in the 
Excel function. The Excel help documentation explains the syntax of  
LOGINV(probability,mean,standard_dev) and gives an example. If one uses 
the Excel function LOGINV(RAND(),mean,standard_dev) the result is the 
same as with Gnumeric's RANDLOGNORM function. Actually, looking at the 
Excel help file was how I came to properly interpret the Gnumeric function.

My original point, perhaps poorly made, was that the help documentation 
for Gnumeric was not very helpful. I agree using semantics that are 
consistent with Excel is a good approach, but the Gnumeric help 
documentation should stand on its own should it not?.

Morten is spot on that R gives better consistency. If it were only 
myself, R fills the ticket, but one of my goals is to have my students 
accept Gnumeric as a viable (or preferable) alternate to Excel. Thus my 
concern with help documentation.

As mentioned in the earlier post, I am new to Gnumeric and this list, so 
am traveling the learning curve. Thanks.

Carl


Morten Welinder wrote:
> It would make sense to first verify that LOGNORMAL does what it is
> supposed to do, i.e., what it does for Excel.  It is well known that
> arguments to Excel's statistical functions can be illogical or worse.
> Nevertheless, changing the semantics away from Excel's is only going
> to make things worse.
>
> If you need consistency, use the "R" functions: R.DLNORM, R.PLNORM,
> and R.QLNORM.
>
> Morten
>
>