[ppml] Combining Forecasts

[michael.dillon at bt.com]

> This is a recent change in Huston's predictions. A few months 
> difference from his previous prediction in July.  Google 
> cache of this page from Aug 4, shows April 16th, 2010.  Tony 
> Hain now says April 2010.
> 
> This seems to be a lot of variation from July, when both said 
> March 2010.  This deserves further investigation.  I suspect 
> that in Huston's case, if he doesn't update the data from 
> ARIN, etc, his program will see this as no new allocations 
> and compute a new (but wrong) exhaustion date. I'll see if 
> this is the case.

Combining forecasts by averaging them has been shown to improve the
accuracy of forecasting. Perhaps it is time to dig some of the other
forecasts out of the woodwork so that we have more than just Tony's and
Geoff's work. 

If you are interested in the study of combining forecasts, then check
this paper
http://www.forecastingprinciples.com/paperpdf/Combining%20forecasts.pdf
and the annotated bibliography mentioned in the references.


> IPv4 is not a sinking ship at all.  People said Fax would be 
> totally obsolete in the 1990s, replaced by email.  Now we use 
> both. Likewise, we will continue to use both IPv4 and IPv6.  
> There will continue to be IPv4 applications, because IPv6 is 
> too heavy for some applications. Text messaging and cheap 
> cell phones did not entirely replace pagers.  

TV made radio obsolete. CDs made vinyl obsolete. The automobile made
horses obsolete. If we can learn anything from history, it is that old
technologies that were widespread almost always find a niche and hang
around for a lot longer than people imagine. The ones that die out
quickly are the ones which were never very widespread like Banyan VINES
or vacuum tube computers or drum memory or 8-track tapes.

If you want to run TCP/IP on a Z80 (remember those?) then you will
probably keep on running IPv4 until they stop manufacturing Z80 chips.
http://www.computer-solutions.co.uk/chipdev/micronet.htm And yes, you
can still buy Z80s today
http://www.zilog.com/products/family.asp?fam=220

--Michael Dillon