The explicit specification of location has traditionally been
geometric
(e.g., as latitude-longitude pairs of numbers). However, few people
know them nor do they use them to communicate or receive them from
others in this way. Instead, people are used to specify a location
textually, which includes verbally, often on a mobile device where a
virtual keyboard is always present. Textual specifications have
numerous benefits. First, they are very useful for searching for text
documents for relevance to a particular location or set of locations.
Second, textual location specifications are general in the sense that
when they are used in a query, there is no need to be concerned about
their internal representation (e.g., a city like Los Angeles can be a
point or an area or every a boundary).
In this project, the underlying textual data is accessed via a map
query interface using direct manipulation actions such as pan
and zoom to navigate the data. The advantage of these actions is that
the act of pointing at a location (e.g., by the appropriate
positioning of a pointing device or gesturing appropriately) and
making the interpretation of the precision of this positioning
specification dependent on the zoom level is equivalent to permitting
spatial synonyms.
This project is a response to
shortcomings observed in systems and applications such as NewsStand
and TwitterStand which make use of a map interface to access documents
such as news and tweets, respectively.
(1) Detecting tweets about local events. This is difficult as
only a few people may be posting related tweets in contrast to global
events where many people post tweets thereby making it easier to
detect them. (2) Improving the resolution of ambiguous location names
when retrieving documents using textually-specified locations by
developing more appropriate precision and recall evaluation metrics.
(3) Enabling domain-specific tracking of mentions of events such as
crimes and diseases in news and social media such as Twitter over time
with the aid of heat maps which may have an impact on public safety
and health. (4) Allowing users to specify the desired domain in (3)
as well as infer it by use of exemplars. (5) Improving NewsStand's
clustering by using word2vec which makes better use of semantics
than the currently used TF-IDF. This clustering is used for the
actual documents and their associated images and videos. This has
the advantage of enabling the detection of similar images on semantics
which are the contents of the related news articles and tweets rather
than local features such as color, texture, etc. This has the
potential for much more sophisticated retrieval than just using image
captions or tagging the images with humanly generated keywords. Note
that no humans are involved in the image similarity process.
Wei, Hong and Zhou, Hao and Sankaranarayanan, Jagan and Sengupta,
Sudipta and Samet, Hanan. (2019). DeLLe: Detecting Latest Local Events
from Geotagged Tweets. Proceedings of the Third ACM SIGSPATIAL
Workshop on Analytics for Local Events and News (LENS 2019). 1 to
10. doi:10.1145/3356473.3365188.
H. Wei, J. Sankaranarayanan, H. Samet Enhancing local live tweet
stream to detect news. GeoInformatica, 24:411-441, April 2020.
doi:10.1007/s10707-019-00392-9.
Wei, Hong and Anjaria, Janit and Samet, Hanan. (2019). Learning
Embeddings of Spatial, Textual and Temporal Entities in Geotagged
Tweets. Proceedings of the 27th ACM SIGSPATIAL International
Conference on Advances in Geographic Information Systems. 484 to
487. doi:10.1145/3347146.3359108
Yadamjav, Munkh-Erdene and Bao, Zhifeng and Choudhury, Farhana M. and
Samet, Hanan and Zheng, Baihua. (2019). Querying Continuous Recurrent
Convoys of Interest. Proceedings of the 27th ACM SIGSPATIAL
International Conference on Advances in Geographic Information
Systems. 436 to 439. doi:10.1145/3347146.3359083
Ayhan, Samet and Costas, Pablo and Samet, Hanan. (2019). A Data-driven
Framework for Long-Range Aircraft Conflict Detection and Resolution.
ACM Transactions on Spatial Algorithms and Systems. 5 (4) 1 to
23. Status = Deposited in NSF-PAR doi:10.1145/3328832
Ayhan, Samet and Samet, Hanan. (2019). Data Management and Analytics
System for Online Flight Conformance Monitoring and Anomaly
Detection. Proceedings of the 27th ACM SIGSPATIAL International
Conference on Advances in Geographic Information Systems. 219 to
228. doi:10.1145/3347146.3359378.
Cao, Hancheng and Sankaranarayanan, Jagan and Feng, Jie and Li, Yong
and Samet, Hanan. (2019). Understanding Metropolitan Crowd Mobility
via Mobile Cellular Accessing Data. ACM Transactions on Spatial
Algoriths and Systems. 5 (2) 1 to 18. doi:10.1145/3323345
Cao, Hancheng and Xu, Fengli and Sankaranarayanan, Jagan and Li, Yong
and Samet, Hanan. (2020). Habit2vec: Trajectory Semantic Embedding for
Living Pattern Recognition in Population. IEEE Transactions on Mobile
Computing. 19 (5) 1096 to 1108. doi:10.1109/TMC.2019.2902403.
Peng, Shangfu and Sankaranarayanan, Jagan and Samet,
Hanan. (2018). DOS: a spatial system offering extremely
high-throughput road distance computations. 26th ACM SIGSPATIAL
International Conference on Advances in Geographic Information
Systems. 199 to 208. doi:10.1145/3274895.3274898.
Wei, Hong and Fellegara, Riccardo and Wang, Yin and De Floriani, Leila
and Samet, Hanan. (2018). Multi-level filtering to retrieve similar
trajectories under the Frechet distance. 26th ACM SIGSPATIAL
International Conference on Advances in Geographic Information
Systems. 600 to 603. doi:10.1145/3274895.3274978.
Theses
Janit Anjaria (2019). DistLearn: Learning to Compute Distance between
Trajectories. M.S. Scholarly Paper.
Samet Ayhan (2019):
Airspace Planning for Optimal Capacity, Efficiency, and Safety Using
Analytics. Ph.D. Thesis.
Hao Li(2018) (with Tom Goldstein):
Toward Fast and Efficient Representation Learning. Ph.D. Thesis.
Shangfu Peng (2019):
High-Throughput Network Distance Computations for Spatial
Analytics Inside Any Store. Ph.D. Thesis.
Hong Wei (2020):
Local News and Event Detection in Twitter. Ph.D. Thesis.
Programs/Software
NewsStand. An
example application of a general framework that enables people to search for
information with a map-query interface. The NewsStand system monitors the
output of more than 10,000 RSS news feeds and incorporates new articles
within minutes of publication. Each article undergoes a geotagging
procedure, where location references are identified and interpreted,
allowing us to associate each article with the geographic locations that it
mentions.
An article describing the NewsStand system appears as the cover article
of the October 2014 issue of the Communications of the ACM. It can be
found at
http://tinyurl.com/newsstand-cacm.
A cached version can be found at
http://www.cs.umd.edu/~hjs/pubs/cacm-newsstand.pdf
The original NewsStand article in the 2008 SIGSPATIAL conference
received the 2018 SIGSPATIAL 10 year impact award.
ACM also made a video about NewsStand to accompany the above article
which can be viewed at
https://vimeo.com/106352925
TwitterStand. The
TwitterStand system monitors a tweet stream where each tweet
undergoes a geotagging procedure, where location references are
identified and interpreted, allowing us to associate each article
with the geographic locations that it mentions explicitly or that
it is associated with as a result of the news or news tweet cluster
with which it is associated based on data from the NewsStand system..
PhotoStand. An
image based browser that enables the use of a map query interface to
retrieve news photos associated with news articles that are in turn
associated with the principal locations that they mention, based on the data
from the NewsStand system.
Preliminary Publications
Wei, Hong and Zhou, Hao and Sankaranarayanan, Jagan and Sengupta,
Sudipta and Samet, Hanan. (2018). Detecting latest local events from
geotagged tweet streams. 26th ACM SIGSPATIAL International Conference
on Advances in Geographic Information Systems. 520 to 523.
doi:10.1145/3274895.3274977.
Wei, H and Sankaranarayanan, J and Samet, H.. (2018). Enhancing Local
Live Tweet Stream to Detect News. Second ACM SIGSPATIAL Workshop on
Analytics for Local Events and News (LENS 2018).
doi:10.1145/3282866.3282868.
M. E. Yadamjav, Z. Bao, F. Choudhury, B. Zheng, H. Samet (2020). Querying
recurrent convoys in a sliding window. ACM Transactions on Intelligent
Systems and Technology. To appear.
Ayhan, Samet and Costas, Pablo and Samet, Hanan. (2018). Prescriptive
analytics system for long-range aircraft conflict detection and
resolution. 26th ACM SIGSPATIAL International Conference on Advances
in Geographic Information Systems. 239 to 248.
doi:10.1145/3274895.3274947.