Xu Lu, A. Croitoru, Jacek R. Radzikowski, A. Crooks, A. Stefanidis
{"title":"Comparing the spatial characteristics of corresponding cyber and physical communities: a case study","authors":"Xu Lu, A. Croitoru, Jacek R. Radzikowski, A. Crooks, A. Stefanidis","doi":"10.1145/2536689.2536805","DOIUrl":"https://doi.org/10.1145/2536689.2536805","url":null,"abstract":"The proliferation of social media over the past few years is presenting us with unique opportunities to sample opinions and interests at spatial and temporal resolutions previously unheard of. In order to make best use of this information though, we need a better understanding of the degree to which the cyber community that is observed through them can serve as a proxy for the corresponding physical community. In this paper we are making a contribution towards this issue by presenting a case study in which we compare spatial characteristics of a community both in the physical and cyber spaces. The key findings of our analysis relate to the selection of an appropriate level of spatial aggregation for analyzing social media content, and on the effect in the level of participation of the distance from the point of interest.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129953151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Temporal decomposition and semantic enrichment of mobility flows","authors":"C. Coffey, A. Pozdnoukhov","doi":"10.1145/2536689.2536806","DOIUrl":"https://doi.org/10.1145/2536689.2536806","url":null,"abstract":"Mobility data has increasingly grown in volume over the past decade as localisation technologies for capturing mobility flows have become ubiquitous. Novel analytical approaches for understanding and structuring mobility data are now required to support the backend of a new generation of space-time GIS systems. It is increasingly important as GIS is becoming a decision support platform for operations in fleet management, urban data analysis and related applications. This paper applies the machine learning method of probabilistic topic modelling for semantic enrichment of mobility data recorded in terms of trip counts by using geo-referenced social media data. It further explores the questions of causality and correlation, as well as predictability of the obtained semantic decompositions of mobility flows on a real dataset from a bike sharing network.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"7 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113954570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Ribeiro, C. Davis, Diogo Rennó Rocha de Oliveira, Wagner Meira Jr, Tatiana S. Gonçalves, G. Pappa
{"title":"Traffic observatory: a system to detect and locate traffic events and conditions using Twitter","authors":"S. Ribeiro, C. Davis, Diogo Rennó Rocha de Oliveira, Wagner Meira Jr, Tatiana S. Gonçalves, G. Pappa","doi":"10.1145/2442796.2442800","DOIUrl":"https://doi.org/10.1145/2442796.2442800","url":null,"abstract":"Twitter has become one of the most popular platforms for sharing user-generated content, which varies from ordinary conversations to information about recent events. Studies have already showed that the content of tweets has a high degree of correlation with what is going on in the real world. A type of event which is commonly talked about in Twitter is traffic. Aiming to help other drivers, many users tweet about current traffic conditions, and there are even user accounts specialized on the subject. With this in mind, this paper proposes a method to identify traffic events and conditions in Twitter, geocode them, and display them on the Web in real time. Preliminary results showed that the method is able to detect neighborhoods and thoroughfares with a precision that varies from 50 to 90%, depending on the number of places mentioned in the tweets.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124305863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohamed Sarwat, Jie Bao, A. Eldawy, Justin J. Levandoski, A. Magdy, M. Mokbel
{"title":"The anatomy of Sindbad: a location-aware social networking system","authors":"Mohamed Sarwat, Jie Bao, A. Eldawy, Justin J. Levandoski, A. Magdy, M. Mokbel","doi":"10.1145/2442796.2442798","DOIUrl":"https://doi.org/10.1145/2442796.2442798","url":null,"abstract":"This paper features Sindbad; a location-based social networking system. Sindbad supports three new services beyond traditional social networking services, namely, location-aware news feed, location-aware recommender, and location-aware ranking. These new services not only consider social relevance for its users, but they also consider spatial relevance. Since location-aware social networking systems have to deal with large number of users, large number of messages, and user mobility, efficiency and scalability are important issues. To this end, Sindbad encapsulates its three main services inside the query processing engine of PostgreSQL. Usage and internal functionality of Sindbad are implemented with PostgreSQL and Google Maps API. Both a web and android phone applications are built on top of Sindbad for better interaction with the system users.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"99 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127941639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multimodal geo-tagging in social media websites using hierarchical spatial segmentation","authors":"P. Kelm, S. Schmiedeke, T. Sikora","doi":"10.1145/2442796.2442805","DOIUrl":"https://doi.org/10.1145/2442796.2442805","url":null,"abstract":"These days the sharing of photographs and videos is very popular in social networks. Many of these social media websites such as Flickr, Facebook and Youtube allows the user to manually label their uploaded videos with geo-information using a interface for dragging them into the map. However, the manually labelling for a large set of social media is still borring and error-prone. For this reason we present a hierarchical, multi-modal approach for estimating the GPS information. Our approach makes use of external resources like gazetteers to extract toponyms in the metadata and of visual and textual features to identify similar content. First, the national borders detection recognizes the country and its dimension to speed up the estimation and to eliminate geographical ambiguity. Next, we use a database of more than 3.2 million Flickr images to group them together into geographical regions and to build a hierarchical model. A fusion of visual and textual methods for different granularities is used to classify the videos' location into possible regions. The Flickr videos are tagged with the geo-information of the most similar training image within the regions that is previously filtered by the probabilistic model for each test video. In comparison with existing GPS estimation and image retrieval approaches at the Placing Task 2011 we will show the effectiveness and high accuracy relative to the state-of-the art solutions.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122747920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Can off-the-shelf object detectors be used to extract geographic information from geo-referenced social multimedia?","authors":"Daniel Leung, S. Newsam","doi":"10.1145/2442796.2442801","DOIUrl":"https://doi.org/10.1145/2442796.2442801","url":null,"abstract":"On-line photo sharing websites such as Flickr not only allow users to share their precious memories with others, they also act as a repository of all kinds of information carried by their photos and tags. The objective of this work is to perform geographic knowledge discovery by crowdsourcing of geographic information from Flickr's geo-referenced photo collections. In particular, we explore the idea of extracting geographic information semantically for land-use classification by applying state-of-the art object and concept detectors directly to the photo collections. Our results suggest that even though the detectors are able to produce distinctive spatial distributions of different objects, performing land-use classification using user contributed geo-referenced photos remains a challenging problem due to the wide variety of photos available in the collections.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128452890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"SNAIR: a framework for personalised recommendations based on social network analysis","authors":"Saajan Shridhar, Mithleshwar Lakhanpuria, Abhishek Charak, Ankur Gupta, Swapan Shridhar","doi":"10.1145/2442796.2442809","DOIUrl":"https://doi.org/10.1145/2442796.2442809","url":null,"abstract":"This paper presents a social network mining and analysis framework delivering personalized recommendations to the user in a privacy-preserving manner. Recommendations are based on the core elements of social media namely location, interests, work domain, gender, friends and nature of interactions. These elements are mined from the multiple social networking applications utilized by the user. The user controls the source and nature of recommendations received through configurable privacy filters.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114883439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"TweoLocator: a non-intrusive geographical locator system for Twitter","authors":"Rodolfo Gonzalez, Gerardo Figueroa, Yi-Shin Chen","doi":"10.1145/2442796.2442804","DOIUrl":"https://doi.org/10.1145/2442796.2442804","url":null,"abstract":"In the last decade, the Internet has seen the rise of social networking as the number one online activity worldwide. To estimate the geographical location of users of social networks at a particular moment, we propose an approach to geo-tag Twitter users based only on the content of their posts. These data can later be used for local sentiment analysis, emergency detection, finding a missing person, and other novel location-based purposes. Our approach carries out a semantic analysis of tweet content to infer where in the globe a particular user is located at a given time. Based on our experimental results, conducted through Amazon Mechanical Turk, the proposed framework was evaluated by 93 evaluators who assessed 654 twitter user profiles and 2,165 tweets from 17 countries. Our system inferred some geographical information for 81% of evaluated profiles. Results show 79% accuracy in identifying the user's country and 66% accuracy in identifying the user's current location. This high accuracy shows that our proposed method is feasible and effective.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129615306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
James Caverlee, Zhiyuan Cheng, Wai Gen Yee, Roger Liew, Yuan Liang
{"title":"Public checkins versus private queries: measuring and evaluating spatial preference","authors":"James Caverlee, Zhiyuan Cheng, Wai Gen Yee, Roger Liew, Yuan Liang","doi":"10.1145/2442796.2442806","DOIUrl":"https://doi.org/10.1145/2442796.2442806","url":null,"abstract":"Understanding the spatial preference of mobile and web users is of great significance to creating and improving location-based recommendation systems, travel planners, search engines, and other emerging mobile applications. However, traditional sources of spatial preference -- which reflect the patterns of geo-spatial interest of large numbers of users -- have typically been expensive to collect, proprietary, and unavailable for widespread use. In this paper, we investigate the viability of new publicly-available geospatial information to capture spatial preference. Concretely, we compare a set of 35 million publicly shared check-ins voluntarily generated by users of a popular location sharing service with a set of over 400 million private query logs recorded by a commercial hotel search engine. Although generated by users with fundamentally different intentions, we find common conclusions may be drawn from both data sources -- (i) that the relative geo-spatial \"footprint\" of different locations is surprisingly consistent across both; (ii) that methods to identify significant locations results in similar conclusions; and (iii) that similar performance may be achieved for automatically identifying groups of related locations. These results indicate the viability of publicly shared location information to complement (and replace, in some cases), privately held location information.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133239961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Exploratory analysis on heterogeneous tag-point patterns for ranking and extracting hot-spot related tags","authors":"M. Ruocco, H. Ramampiaro","doi":"10.1145/2442796.2442802","DOIUrl":"https://doi.org/10.1145/2442796.2442802","url":null,"abstract":"The availability of a huge amount of geotagged resources on the web can be exploited to extract new useful information. We propose a set of estimators that are able to evaluate the degree of clustering of the spatial distribution of terms used to tag such geotagged resources. We introduce the concept of tag point pattern to derive indexes from the exploratory analysis by taking advantage of the second order Ripley's K-function, previously used in epidemiology, geo-statistics and ecology. The derived model estimates the degree of aggregation of the geotagged resources, taking into account the heterogeneity of the spatial distribution of the underlying population. Further, thanks to subsampling techniques, our approach is able to handle large datasets. Without losing of generality, we perform our experiments on a dataset derived Flickr pictures, as a use case. This dataset consists of tags that were extracted from a set of 1.2 million of pictures. We evaluate our proposed indexes with respect to their ability to extract tags related to geographical landmarks and hotspots. Our experiments show that we get good results using our estimators.","PeriodicalId":107369,"journal":{"name":"Workshop on Location-based Social Networks","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123130360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}