Re: [dvd-discuss] Interpreting the Jaszi graph

["Baerwulf" <baerwulf(at)echidna.id.au>]

> <http://cyber.law.harvard.edu/openlaw/eldredvashcroft/pubdomain.html>
> 
> I'm completely baffled by this graphic.

As I understand it
 
> o What exactly does the Y axis represent?

The Y axis represents the rate of growth of the public domain
i.e. works entering public domain each year
i.e. dPD/dt
 
> o What is the meaning of the purple area?
>   The grey area?  Is this the number of 
>   works?  Percentage of works?  Something
>   else?

the grey area is the integrated extrapolation of dPd/dt
assuming original conditions (as at 1790)
the purple area is the same but with the extensions of copyright 
accounted for
both are in (relative) number of works 

> o Why doess the graph appear linear, when 
>   the growth of published works has been 
>   exponential?

I think a major assumption has been made but not stated here
(that the rate of creation of new works is linear)

> o Prior to 1978, any work published without
>   proper copyright notice immediately entered 
>   the public domain.  How does this fit in 
>   to the "zero growth" areas of the graph?

I think another assumption has been made
(that all works are copyrighted)

> o During the "zero growth" periods, 1831, 
>   1909, 1962, many works, entered the public 
>   domain due to failure to renew copyright.  
>   Are those not represented on the chart, or 
>   is the number of unrenewed copyrights 
>   negligable?  I thought that it was the 
>   other way around -- that only a very small 
>   percentage of copyrighted works had their 
>   copyright renewed.
> 
> o Note that with the renewal requirement
>   removed, and automatic copyright protection
>   for all works, we ARE now in a situation
>   of zero growth of the public domain --
>   but this is only since 1976.

Again i think that the author has assumed that all
works are renewed
these two assumptions give a worst case scenario.
which is what the berne convention gave us


> o If the public domain was growing at a large
>   "Y" value in 1831, then drops to zero, why
>   does it start at zero 14 years later when
>   copyright expirations resume, instead of 
>   picking up where it left off?

This appears wrong and it should infact start where it 
left off after a period of zero growth.


> Does anyone have a better understanding of 
> this graph?
>
maybe, maybe not :-)

 Nature abhors a vacuum. So does my sister's dog.