objectivity and factoring analysis

[Anonymous]

Nicko van Someren writes:

> The estimate
> of the cost of construction I gave was "some hundreds of
> millions of dollars", a figure by which I still stand.

But what does that mean, to specify (and stand by) the cost of
construction of a factoring machine, without saying anything about how
fast it runs?  Heck, we could factor 1024 bit numbers with a large abacus,
if we don't care about speed.  A cost figure is meaningless unless in the
context of a specific performance goal.

> I was then asked how fast this machine would run and I tried
> to do the calculation on the spot without a copy of the
> proposal to hand, and came up with a figure on the order
> of a second based on very conservative hardware design.
> This figure is *wildly* erroneous as a result of both not
> having the paper to hand and also not even having an
> envelope on the back of which I could scratch notes.

And yet here you say that it took you completely by surprise when someone
asked how fast the machine would run.  In all of your calculations on the
design of the machine, you had apparently never calculated how fast it
would be.

How could this be?  Surely in creating your hundreds of millions
of dollars estimate you must have based that on some kind of speed
consideration.  How else could you create the design?  This seems very
confusing.

And, could you clarify just a few more details, like what was the size
you were assuming for the factor base upper bounds, and equivalently for
the size of the matrix?  This would give us a better understanding of the
requirements you were trying to meet.  And then, could you even go so far
as to discuss clock speeds and numbers of processing and memory elements?
Just at a back of the envelope level of detail?

Adam Back wrote:
> The mocking tone of recent posts about Lucky's call seems quite
> misplaced given the checkered bias and questionable authority of the
> above conflicting claims we've seen quoted.

No, Lucky made a few big mistakes.  First, he invoked Ian Goldberg's
name as a source of the estimate, which was wrong.  Second, he presented
Nicko's estimate as being more authoritative than it actually was,
as Nicko makes clear here.  And third, he fostered panic by precipitously
revoking his key and widely promulgating his "sky is falling" message.

We wouldn't be in this situation of duelling bias and authority if
people would provide some minimal facts and figures rather than making
unsubstantiated claims.

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