Basemap :: Forum

6/1/2010 1:49:31 PM keithdrew76 Posts: 44	Hello Just sharing a published paper with you all, which I mentioned a few months ago to my TPM post - this is the 'sister' paper and first attempt at producing accessibility by weighted journey times. http://www.journalofmaps.com/crossrefMap.php?mid=1069. Any comments/queries are welcome. Keith
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7/29/2010 4:26:40 PM keithdrew76 Posts: 44	This is a direct link to the article - rather than having to sign up to the journal itself - http://www.mirrorservice.org/sites/www.journalofmaps.com/article_depository/europe/Drew_GIS_1241012233.pdf Would be good to know what you think - positive and negative! Keith
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7/30/2010 12:43:09 PM admin Administrator Posts: 146	An interesting read. I agree that having fare included in the software would be great, though unfortunately there is no national dataset of this data and so can't be used. I would be interested to know more on how you decided wait time should be analysed, you mention using headway on a service - this is similar to how frequency networks calculate wait time, though for low frequency networks it was found this wait time was un-realistic. Is this something you found?
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7/30/2010 2:55:10 PM keithdrew76 Posts: 44	Hi Dan Wait time was calculated outside of Accession using GIS - basically using a zoning approach. For high frequency wait time was simply half of headway, for low frequency it was capped to x minutes (can't remember what exactly). If a journey was not possible from A to B then wait time was calculated to the nearest major interchange, and then from the interchange to the destination. Wherever possible assumptions on wait time etc were made in line with WebTAG guidance for modelling. Keith
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