On 03/03/06, Bin Jiang <[log in to unmask]> wrote:
> Usually we compare space syntax measures within a same system, not
> across different systems. This is my perception. Am I wrong?
Well, if you use local integration for a single axial map you *are*
comparing different systems because the number of nodes involved to
calculate this measure vary for each node. It is the same if you
compare global integration between different maps.
Therefore, if you do not agree that RRA / Diamond Shapes provides some
help... forget the whole thing about local integration... just does
not work.
For me it is quite OK.
> I am not convinced by the popular saying that the local integration is a
> good indicator of pedestrian or vehicle flows. Recently I happened to
> get some vehicle observation datasets with pressure-sensed techniques
> (so must be very precise observation). I compared the datasets with
> local integration, and did not end up with a good correlation (R square
> value about 0.5).
I have got the same in this paper:
"Continuity lines: aggregating axial lines to predict vehicular
movement patterns"
http://www.mindwalk.com.br/papers/
That is a problem. I produced a continuity map that reveals clearly
the main street system of my city (Recife, Brazil). But ... correlate
abstract graph properties with real movement is another issue. There
are many other factors, such as attractors, street width, etc.
Therefore, this is just a matter what is the number you accept as a
good proof that the urban grid itself (ignoring the other factors) can
organise movement patterns.
Regards!
Lucas Figueiredo
CASA - Centre for Advanced Spatial Analysis
University College London
1-19 Torrington Place
London WC1E 7HB England
E-mail: [log in to unmask]
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