Talk:Newsvendor model/Archives/2012

Alternate Names

Added section for alternate names.

A Google search for "newsboy problem" (as suggested in a newsgroup post):
http://www.google.com/search?q=site%3Awikipedia.org+%22newsboy+problem%22
returned a hit for only the Italian version of Wikipedia

Google apparently does not index the existing redirect pages:
http://en.wikipedia.org/w/index.php?title=Newsvendor_problem&redirect=no
http://en.wikipedia.org/w/index.php?title=Newsboy_problem&redirect=no

Ac44ck 17:17, 3 May 2007 (UTC)

LOL WUT? --15.203.233.76 (talk) 15:41, 11 March 2009 (UTC)

Someone should post a proof

The numerical example is just plain wrong. Not only is the equation incomplete (it basically reduces to giving Q-star as Dmax*(p-c)/p), but it is not even self-consistent (the answer for the given parameters should be 23, which would be an incorrect stocking level). The equation should give Q-star as μ + z*β*σ, where μ = (Dmax+Dmin)/2, β = (p-c)/p and z = Finv((p-c)/p). Since F is a standard normal distribution, σ can be approximated as (Dmax - Dmin)/8. This returns a value of 63 for the stated parameters. If I were more adept at using the editing tools, I would make these changes myself.

Aloysiuspsd (talk) 22:07, 14 December 2009 (UTC)

I think its the equation that he has started with that is not quite what it should. I struggled a bit with that when I added the normal and lognormal calculations the $F^{-1}$ bit is most troublesome because it does not explain where $\mu$ and $\sigma$ fit in.Pkearney (talk) — Preceding unsigned comment added by Pkearney (talk • contribs) 07:15, 29 July 2012 (UTC)

numerical example is wrong

The optimum solution for the numerical example is 58. I obtained the result empirically (with a random number generator, using a computer).

I suppose the formula that is in the text is incorrect. The answer 58.55 (or 59) is not correct.

Also, in a previous section, the user Aloysiuspsd has an error in his calculations. He is considering that the distribution is normal. The text says it is an uniform distribution.

Hmmm, not sure, it looks right to me. — Preceding unsigned comment added by Pkearney (talk • contribs) 07:10, 29 July 2012 (UTC)

Normal and Log-Normal Examples

I added the normal and lognormal examples

Pkearney (talk) —Preceding undated comment added 07:08, 29 July 2012 (UTC)