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Sorry a critical typo in the previous email - missed NOT: One can use segment as a basic unit, BUT NOT in the way as implemented in Depthmap. On 12/10/2016 11:41 PM, Bin Jiang wrote: > Thanks Alan for sharing your thoughts and arguments! > > I would like to clarify my criticism on some of space syntax methodology > based on my research in particular empirical studies. > > (1) At city level, natural streets are a better representation than > axial lines. There is little doubt on that. In this regard, we have two > empirical studies that proved that natural streets are better than axial > lines or segments. > > https://www.researchgate.net/publication/1764726_Street-Based_Topological_Representations_and_Analyses_for_Predicting_Traffic_Flow_in_GIS > > > http://hig.diva-portal.org/smash/record.jsf?pid=diva2%3A656758&dswid=-1471 > > > (2) at architectural level, axial lines are still a good representation, > since human movement occurs between buildings mainly. In this regard, we > have AxialGen to auto-generate axial lines. > > https://www.researchgate.net/publication/23421243_Automatic_Generation_of_the_Axial_Lines_of_Urban_Environments_to_Capture_What_We_Perceive > > > (3) We have found that why space syntax works, or why space syntax is > able to predict human movement is nothing to do with how human > conceptualize space as indicated by Bill Hillier in several of this > papers. We have proved that both humans and monkeys (or random walkers > in general) had the same traffic flow, because it is the underlying > street structure that determines traffic flow. Or put it in a different > way, at least 60% traffic (sometimes up to 80%) can be accounted for by > the underlying topological structure. We had at least four studies, two > of which adopted agent-based simulations: > > https://www.researchgate.net/publication/2177752_Ranking_Space_for_Predicting_Human_Movement_in_an_Urban_Environment > > > https://www.researchgate.net/publication/45878700_Agent-Based_Simulation_of_Human_Movement_Shaped_by_the_Underlying_Street_Structure > > > https://www.researchgate.net/publication/26858844_Characterizing_the_Human_Mobility_Pattern_in_a_Large_Street_Network > > > and more recently, > > https://www.researchgate.net/publication/281936247_Can_Cognitive_Inferences_be_Made_from_Aggregate_Traffic_Flow_Data > > > (4) Angular segmental representations work, because of topological > rather than geometrical effect. This is in line with natural streets, > because natural streets are defined by a smallest deflection angle, so > essentially angular effect. One can use segment as a basic unit, BUT in > the way as implemented in Depthmap. It must be done through topological > representation of streets or axial lines: see this paper and Section 4.3 > in particular. > > https://www.researchgate.net/publication/1918773_Self-organized_Natural_Roads_for_Predicting_Traffic_Flow_A_Sensitivity_Study > > > > Any comments and criticisms are welcome. > > Cheers. > > Bin > > On 12/10/2016 10:56 PM, Penn, Alan wrote: >> David, >> >> the paper and an open lecture are here: >> http://spacesyntax.tudelft.nl/media/Long%20papers%20I/alan%20penn.pdf >> https://youtu.be/NkePRXxH9D4 >> >> Briefly, we need to be a bit careful about terminology, by which I >> mean that the word ‘agent’ in this case may be misleading, and so >> mustn’t be taken as a direct proxy for the philosophical concept. >> Although we didn't really understand this at the time, the basis of >> our EVAS ‘agent' based representation was in fact a deterministic >> analysis of spatial geometry (and topology for that matter) and as >> such extremely reductive. It happens to have the interesting property >> of incorporating anisotropy (a property of an embodied agent perhaps) >> in its geometric and topological representation. It is however >> entirely deterministic and thus an ‘analysis’ or the environment >> rather than any kind of ‘simulation’ of individuals with any kind of >> autonomous agency aside from randomness. In this sense it is just as >> holistic as any other space syntax representation. >> >> EVAS stands for 'exosomatic visual agent simulation’ since the idea >> was that the representation in memory of the environment might lie >> outside the body in the environment itself (this builds on the space >> syntax notion that intelligibility might be a property of the >> environment itself). The thesis is that as society constructs cities >> through an essentially distributed process involving many different >> decision takers it builds into the geometry, topology and other >> aspects of the architecture - e.g. scale, land use, decoration etc. - >> patterns of relations between properties that make the world >> meaningful. This all sits ‘out there’ in the world and is readable by >> all the individual users of the environment in common. It is the >> distributed process of production of the built environment that leads >> to it being holistic and so amenable to syntax type analysis. >> >> So one of the experiments we did was to place ‘merchandise’ in a >> series of environments. Different ‘flavours’ of merchandise were >> represented as a vectors on the surface of building surfaces in the >> environment. Agents were given a ’taste’ for a specific ‘flavour’ >> (the hunger was also represented as a vector). That way the agent >> could search the environment looking for merchandise that matched >> it’s taste. This allowed us to measure how long it took agents to >> find merchandise that best matched their taste under different >> spatial conditions. This is about as far as we have got so far on the >> specific ‘shopping’ activity work, but is obviously one reason that >> we developed the so called ‘agent’ approach in that it allows us to >> experiment with the twin notions of configuration and attraction as >> drivers of human behaviour. >> >> A paper on this is here: >> http://dx.doi.org/10.1057/palgrave.udi.9000120 >> >> I am not sure whether this would count as a ‘manifesto’, but >> certainly these are some of the motivations behind developing this >> methodology. What it is not, though, is something that would pass >> muster amongst social simulators as any kind of simulation in which >> the entities had any kind of ‘agency’. For that they would need >> beliefs, desires and intentions as well as memory and some ability to >> compute and so adapt behaviours depending upon their perceptions. In >> this sense it is really an extension of space syntax representation >> based analysis, but extending the range of kinds of things that we >> incorporate in the representation (eg. forward face vision, >> attractors in they environment). >> >> Now, Bin often seems to come back with a criticism of these kind of >> developments in methodology. I find that hard to understand since >> what really matters is the empirical utility of a methodology - does >> it cast light on the phenomena we observe in the world? Angular >> segmental representations clearly do since they account empirically >> for observed human movement behaviours better than axial or ‘named >> streets’ although these seem not to have been subjected to the same >> level of testing against empirical movement data. I believe that the >> agent simulations also do. This is not to detract from the simplicity >> and elegance of the axial representation. >> >> All the best, >> >> Alan >> >> >> >> >> >> >>> On 10 Dec 2016, at 19:18, David Seamon <[log in to unmask]> wrote: >>> >>> Alan, >>> >>> You mention your paper on the IKEA research: might you provide a >>> reference? >>> >>> I understand your point about embodiment, though there is the >>> phenomenological question of reductive activation in that the >>> "agent" is limited in what its environmental and spatial >>> "experiences" are. But I appreciate the direction you're attempting >>> to move. >>> >>> One thing regarding the IKEA situation is that I don't see how the >>> agent-based account can incorporate the merchandise displays along >>> the sales route. The IKEA experience is more like a "stroll" than a >>> trip with intention. I understand why some shoppers feel >>> uncomfortable in an IKEA showroom space because one is quickly >>> disoriented, and if one starts to try to figure out where he or she >>> is, it becomes annoying. But my sense is (and I've only been to an >>> IKEA store twice so keep that in mind) that most shoppers aren't too >>> bothered because there is so much to see (and buy). So we move into >>> a phenomenology of different movement and pathway experiences >>> (stroll vs. constitutional vs. walk to work vs. walk through park >>> etc.). In other words, not all movements are the same experientially. >>> >>> My larger confusion is what the "agent approach" has to do with >>> space syntax, which to me is singular because it is topological and >>> thereby holistic. The "agent perspective" is somewhat "global" in >>> that the agent makes use of visual permeability. But it does seem to >>> me that the emphasis remains more partial in that the amount of >>> movement on a particular pathway, grounded in degree of integration >>> in the pathway system, is somehow lost. >>> >>> Do you see the agent-based work as integral to space syntax theory, >>> or should it be considered something different? If folks there are >>> beginning to integrate it into space syntax theory, then it would be >>> helpful to have a "manifesto" as to why. I'm not aware of any such >>> discussion and would like to know of it, if has begun. >>> >>> David Seamon >>> >>> p.s. I apologize for starting new threads each time I post. For some >>> reason, my "return email" for this list serve won't work. Reem is >>> always kind to tell me "didn't go through" so I then post a new >>> email. Thanks, Reem! > > -- > -------------------------------------------------------- > Bin Jiang > Division of GIScience > Faculty of Engineering and Sustainable Development > University of Gävle, SE-801 76 Gävle, Sweden > Phone: +46-26-64 8901 Fax: +46-26-64 8758 > Email: [log in to unmask] Web: http://fromto.hig.se/~bjg/ > -------------------------------------------------------- > Academic Editor: PLOS ONE > Associate Editor: Cartographica > > BinsArXiv: http://arxiv.org/a/jiang_b_1 > Axwoman: http://fromto.hig.se/~bjg/axwoman/ > ICA: https://sites.google.com/site/commissionofica/ > Geomatics: http://fromto.hig.se/~bjg/geomaticsprogram/ > RG: https://www.researchgate.net/profile/Bin_Jiang3 > > [Högskolan i Gävle] > > Högskolan i Gävle, 801 76 Gävle • 026 64 85 00 • > www.hig.se<http://www.hig.se> > > För en hållbar livsmiljö för människan > > University of Gävle, SE-801 76 Gävle, Sweden • +46 (0) 26 64 85 00 • > www.hig.se<http://www.hig.se> -- -------------------------------------------------------- Bin Jiang Division of GIScience Faculty of Engineering and Sustainable Development University of Gävle, SE-801 76 Gävle, Sweden Phone: +46-26-64 8901 Fax: +46-26-64 8758 Email: [log in to unmask] Web: http://fromto.hig.se/~bjg/ -------------------------------------------------------- Academic Editor: PLOS ONE Associate Editor: Cartographica BinsArXiv: http://arxiv.org/a/jiang_b_1 Axwoman: http://fromto.hig.se/~bjg/axwoman/ ICA: https://sites.google.com/site/commissionofica/ Geomatics: http://fromto.hig.se/~bjg/geomaticsprogram/ RG: https://www.researchgate.net/profile/Bin_Jiang3 [Högskolan i Gävle] Högskolan i Gävle, 801 76 Gävle • 026 64 85 00 • www.hig.se<http://www.hig.se> För en hållbar livsmiljö för människan University of Gävle, SE-801 76 Gävle, Sweden • +46 (0) 26 64 85 00 • www.hig.se<http://www.hig.se>