The short answer is yes, 'betweenness' is included in Depthmap, and it
is called 'choice'.
The long answer requires Shinichi Iida to explain some intricate details
about deciding between pairs of shortest paths when two paths have the
exact same length.
Since paths of exactly the same length are rare in angular maps,
betweenness and choice (radius n) can be generally considered to be the
same thing in angular segment analysis.
Alasdair
Martin Tomko wrote:
> Dear Alan,
> yes, I am aware of the different "versions" of betweenness, also from
> network analysis. I was talking about the "pure", or global value -
> betweennes as a portion of shortest trips between all combinations of
> nodes leading through a certain node/path (axial line,...). My problem
> is rather if/where I can find this measure in the standard space syntax
> tools, say depthmap, mindwalk? Is it available? I did not find these
> measures, so I assumed that it may be a confusion of terminology. After
> searching in the social logic of space, I did not find betweenness
> anywhere in the index (searched for betweenness and centrality as well).
> I was also wondering if there is a relation between betweenness and
> integration (p. 108, seems to be the synonym of RA?), but from its
> definition (through mean depth, which I am still trying to get familiar
> with), I was not able to find out.
> I think this is only my problem due to the fact that I am not used to
> the terminology (syntactic spaces,...). Ah well, heritage of a different
> background, I guess, mea culpa :)
> Back to the point - I know that in some space syntax papers the measure
> of betweenness is widely used, as was wondering where it is hiding in
> the tools. Any idea?
> Thanks
> Martin
>
> P.S. I hope that these is not boring for the rest of the list, as I say,
> I am just getting into the area. Thanks for the help!
>
> ----------------------------------------------
> Ing. Martin Tomko
> PhD. candidate
>
> CRC for Spatial Information
> Department of Geomatics
> University of Melbourne
> Victoria 3010
> Australia
>
> phone +61 3 8344 9179
> fax +61 3 9349 5185
> email [log in to unmask]
> url http://www.geom.unimelb.edu.au/tomko
> url http://www.spatialinformationscience.org
> url http://www.crcsi.com.au
> ----------------------------------------------
>
> Alan Penn wrote:
>
>> Martin,
>>
>> 'betweenness' covers a whole series of measures including global and
>> radius
>> choice. The main concept is to consider all 'shortest' trips from all
>> nodes
>> to all other nodes and then to consider the number of those trips that
>> pass
>> through any node. Radius versions look at trips between all nodes
>> within the
>> radius. Now, there are a number of variations in how this can be
>> measured.
>> First, in the consideration of the kind of 'distance' that can be used to
>> select the 'shortest' route (eg. metric, topological (ie. steps from
>> node to
>> node) or angular). Second, in what you do when two routes are tied on
>> distance (do the trips subdivide between alternatives, or is a random or
>> other selection made). Third, do you include origins and destinations
>> in the
>> trip count. Etc.
>>
>> You can see the scope for terminological proliferation :-)
>> Alan
>>
>>> Dear list,
>>> Again, my troubles with space syntax terminology, I was wondering what
>>> is the term used in Mindwalk/Depthmap for Betweenness (more properly,
>>> betweenness centrality, as defined in graph theory).
>>> Thanks a lot
>>> Martin
>>> --
>>>
>>> ----------------------------------------------
>>> Ing. Martin Tomko
>>> PhD. candidate
>>>
>>> CRC for Spatial Information
>>> Department of Geomatics
>>> University of Melbourne
>>> Victoria 3010
>>> Australia
>>>
>>> phone +61 3 8344 9179
>>> fax +61 3 9349 5185
>>> email [log in to unmask]
>>> url http://www.geom.unimelb.edu.au/tomko
>>> url http://www.spatialinformationscience.org
>>> url http://www.crcsi.com.au
>>> ----------------------------------------------
>>
>>
>
>
--
Alasdair Turner
Course Director
MSc Adaptive Architecture and Computation
Bartlett School of Graduate Studies
UCL Gower Street LONDON WC1E 6BT
http://www.aac.bartlett.ucl.ac.uk/
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