[Excel] - IG distribution

[RefUser]

hi all,
how do i find inverse gaussian distribution and values in excel?

thanks!

 

[Dason]

What do you mean by that? Do you want CDF values? Random deviates from the IG distribution? Density values?

 

[RefUser]

yes, CDF.
i need the equivalent to normdist and norminv for gaussian dist...

 

[gianmarco]

Hi,
have you tried this?

Hope it helps
Regards
Gm

 

[Dason]

That seems to be for the normal distribution but the OP is asking about the Inverse Gaussian distribution.

 

[gianmarco]

Oops...yes...I will try and give another look at the web.
Thanks Dason

Gm

 

[Dason]

I don't do anything with excel but it seems that if you have a function for the standard normal cdf (which excel does) then you could program the cdf for the inverse gaussian relatively easily: http://en.wikipedia.org/wiki/Inverse_Gaussian_distribution

 

[RefUser]

I don't do anything with excel but it seems that if you have a function for the standard normal cdf (which excel does) then you could program the cdf for the inverse gaussian relatively easily: http://en.wikipedia.org/wiki/Inverse_Gaussian_distribution

Thanks!
that's very helpful!

 

[RefUser]

one last question:
is there a way to get inverted values of IG, like norminv or gammainv in excel?

 

[RefUser]

ok, in case anyone sees this thread, a simple way to find IG quantiles is through goal seek:

make one column of "wrong" x
set these xs in IG CDF function
and then change the wrong x cell to the wanted distribution, since F(x)=distribution.

 

[Dason]

I don't understand what you're saying.

But I think you're just finding quantiles by plugging values into the CDF until you find a value that is close enough to what you want.

 

[RefUser]

that's exactly what i meant...