Rui,
I think that the point people are making is actually about street names. Now
that we have nice map data with street names attached it is relatively
straightforward to aggregate segments according to name. Thus Oxford Street
and New Oxford Street would have separate existence (although they are
mainly covered by a single axial line) while the Balls Pond Road would be a
single entity in spite of it being quite sinuous and made up of many axial
lines (but only one continuity line, Lucas?). At this point I would argue by
reference to old Will:
Romeo and Juliet, 1594:
JULIET:
'Tis but thy name that is my enemy;
Thou art thyself, though not a Montague.
What's Montague? it is nor hand, nor foot,
Nor arm, nor face, nor any other part
Belonging to a man. O, be some other name!
What's in a name? that which we call a rose
By any other name would smell as sweet;
So Romeo would, were he not Romeo call'd,
Retain that dear perfection which he owes
Without that title. Romeo, doff thy name,
And for that name which is no part of thee
Take all myself.
All the best,
Alan
>
> Alan,
>
> you make an obvious point: we KNOW that the ramp at Torrington Plc is not
> a street (I would think the same for the emergency access to UCH). But
> that seems to require non-geometric information to be combined with the
> topological data?
>
> So what IS a street?
>
> Rui
>
>
> >The more problematic street segments on OS
> >Mastermap are the very short bits that go round traffic bollards in the
> >middle of roads and at junctions - perhaps it is these that give rise to
> the
> >curve at the tail of the distribution? Sticking to geometry based
> >definitions seems to me to be much simpler than semantic or heuristic
> >definitions for this kind of thing.
> >
> >
> >Alan
> >
> >>
> >> Lucas
> >>
> >> A question: If we include, following 'TeleAtlas' for instance, to map
> such
> >> countless bits of space as 'The ramp to the car park at 1-19 Torrington
> >> Plc' or 'The entrance to the emergency services at UCH' into a street
> >> network, could it change its degree distribution from a 'log-normal' to
> >> a 'power-law'? If so, can we really claim that the degree distribution
> of
> >> street networks does not follow a power law but a log-normal?
> >>
> >> Regards,
> >> Hoon
> >>
> >>
> >> >On Thu, 31 May 2007 19:24:49 +0100, Lucas Figueiredo
> >> ><[log in to unmask]> wrote:
> >> >
> >> >>On 31/05/07, Rui Carvalho <[log in to unmask]> wrote:
> >> >>> Pitty no one knows what a street is...
> >> >>
> >> >>Certainly it is not a segment (or route) between two junctions.
> >> >>Otherwise we would have things like "Oxford Street sector A, B, C"
> and
> >> >>so on...
> >> >
> >> >The ramp to the car park at 1-19 Torrington Plc. This comes in GPS car
> >> >navigation systems as a decision point? is it a street?
> >> >
> >> >The entrance to the emergency services at UCH (that's UCL Hospital for
> >> non
> >> >Londoners). Is it a street?
> >> >
> >> >This question appears when you process data from services like
> TeleAtlas
> >> -
> >> >the most accurate data available on street networks...
> >> >
> >> >Looks like Alan should organize that 'mass observation' on what a
> street
> >> >is after all...
> >> >
> >> >Comments welcome!
> >> >
> >> >Rui
> >> >
> >> >
> >> >>
> >> >>Regards,
> >> >>
> >> >>Lucas Figueiredo
> >> >>http://www.flickr.com/photos/lucasfigueiredo/
> >> >>
> >> >>Mindwalk
> >> >>http://www.mindwalk.com.br
> >>
> >========================================================================
> >========================================================================
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