Temporal sampling and service frequency harmonics in transit accessibility evaluation

In the context of public transit networks, repeated calculation of accessibility at multiple departure times provides a more robust representation of local accessibility. However, these calculations can require significant amounts of time and/or computing power. One way to reduce these requirements...

Full description

Saved in:
Bibliographic Details
Main Authors: Andrew Owen, Brendan Murphy
Format: Article
Language:English
Published: University of Minnesota Libraries Publishing 2019-12-01
Series:Journal of Transport and Land Use
Subjects:
Online Access:https://www.jtlu.org/index.php/jtlu/article/view/1379
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850229411402481664
author Andrew Owen
Brendan Murphy
author_facet Andrew Owen
Brendan Murphy
author_sort Andrew Owen
collection DOAJ
description In the context of public transit networks, repeated calculation of accessibility at multiple departure times provides a more robust representation of local accessibility. However, these calculations can require significant amounts of time and/or computing power. One way to reduce these requirements is to calculate accessibility only for a sample of time points over a time window of interest, rather than every one. To date, many accessibility evaluation projects have employed temporal sampling strategies, but the effects of different strategies have not been investigated and their performance has not been compared. Using detailed block-level accessibility calculated at 1-minute intervals as a reference dataset, four different temporal sampling strategies are evaluated using aggregate sample error metrics as well as indicators of spatially clustered error. Systematic sampling at a regular interval performs well on average but is susceptible to spatially-clustered harmonic error effects which may bias aggregate accessibility results. A constrained random walk sampling strategy provides slightly worse average sample error, but eliminates the risk of harmonic error effects.
format Article
id doaj-art-1f97b980168443b696eb22a3a8a6cd90
institution OA Journals
issn 1938-7849
language English
publishDate 2019-12-01
publisher University of Minnesota Libraries Publishing
record_format Article
series Journal of Transport and Land Use
spelling doaj-art-1f97b980168443b696eb22a3a8a6cd902025-08-20T02:04:14ZengUniversity of Minnesota Libraries PublishingJournal of Transport and Land Use1938-78492019-12-01121Temporal sampling and service frequency harmonics in transit accessibility evaluationAndrew Owen0Brendan Murphy1Accessibility Observatory University of Minnesota Center for Transportation StudiesAccessibility Observatory University of Minnesota Center for Transportation StudiesIn the context of public transit networks, repeated calculation of accessibility at multiple departure times provides a more robust representation of local accessibility. However, these calculations can require significant amounts of time and/or computing power. One way to reduce these requirements is to calculate accessibility only for a sample of time points over a time window of interest, rather than every one. To date, many accessibility evaluation projects have employed temporal sampling strategies, but the effects of different strategies have not been investigated and their performance has not been compared. Using detailed block-level accessibility calculated at 1-minute intervals as a reference dataset, four different temporal sampling strategies are evaluated using aggregate sample error metrics as well as indicators of spatially clustered error. Systematic sampling at a regular interval performs well on average but is susceptible to spatially-clustered harmonic error effects which may bias aggregate accessibility results. A constrained random walk sampling strategy provides slightly worse average sample error, but eliminates the risk of harmonic error effects.https://www.jtlu.org/index.php/jtlu/article/view/1379transit accessibilitytemporal samplingspatial analytics
spellingShingle Andrew Owen
Brendan Murphy
Temporal sampling and service frequency harmonics in transit accessibility evaluation
Journal of Transport and Land Use
transit accessibility
temporal sampling
spatial analytics
title Temporal sampling and service frequency harmonics in transit accessibility evaluation
title_full Temporal sampling and service frequency harmonics in transit accessibility evaluation
title_fullStr Temporal sampling and service frequency harmonics in transit accessibility evaluation
title_full_unstemmed Temporal sampling and service frequency harmonics in transit accessibility evaluation
title_short Temporal sampling and service frequency harmonics in transit accessibility evaluation
title_sort temporal sampling and service frequency harmonics in transit accessibility evaluation
topic transit accessibility
temporal sampling
spatial analytics
url https://www.jtlu.org/index.php/jtlu/article/view/1379
work_keys_str_mv AT andrewowen temporalsamplingandservicefrequencyharmonicsintransitaccessibilityevaluation
AT brendanmurphy temporalsamplingandservicefrequencyharmonicsintransitaccessibilityevaluation