238 research outputs found
Philosophical Foundations of GeoAI: Exploring Sustainability, Diversity, and Bias in GeoAI and Spatial Data Science
This chapter presents some of the fundamental assumptions and principles that
could form the philosophical foundation of GeoAI and spatial data science.
Instead of reviewing the well-established characteristics of spatial data
(analysis), including interaction, neighborhoods, and autocorrelation, the
chapter highlights themes such as sustainability, bias in training data,
diversity in schema knowledge, and the (potential lack of) neutrality of GeoAI
systems from a unifying ethical perspective. Reflecting on our profession's
ethical implications will assist us in conducting potentially disruptive
research more responsibly, identifying pitfalls in designing, training, and
deploying GeoAI-based systems, and developing a shared understanding of the
benefits but also potential dangers of artificial intelligence and machine
learning research across academic fields, all while sharing our unique
(geo)spatial perspective with others.Comment: Final Draf
Domestic insurers in Poland and the global crisis
The article contains the analysis of the impact of global crisis on Polish insurance sector. The main areas of the crisis impact on the activity of Polish insurance companies has so far been the change in the assets value and the associated decline in the profitability of investment activity. The danger arising from the economic downturn has not been realized so far in the Polish insurance sector. Although the premium written is high, the structure of the portfolio in life insurances is changing. In 2008, however, a significant retreat from saving insurance policies with capital funds in the direction of structured products is observed. A significant increase in premiums written resulted in a good financial situation of Polish insurance companies. Despite the turmoil in financial markets it also seems that solvency of Polish insurance sector is unthreatened as measured by statutory ratios.insurance companies, Polish insurance market, global crisis
Open and Transparent: The Review Process of the Semantic Web Journal
While open access is established in the world of academic publishing, open reviews are rare. The Semantic Web journal goes further than just open review by implementing an open and transparent review process in which reviews are publicly available, and the assigned editors and reviewers are known by name, and are published together with accepted manuscripts. In this article we introduce the steps to realize such a process from the conceptual design, over the implementation, a overview of the results so far, and up to lessons learned
An Empirical Study on the Names of Points of Interest and Their Changes with Geographic Distance
While Points Of Interest (POIs), such as restaurants, hotels, and barber shops, are part of urban areas irrespective of their specific locations, the names of these POIs often reveal valuable information related to local culture, landmarks, influential families, figures, events, and so on. Place names have long been studied by geographers, e.g., to understand their origins and relations to family names. However, there is a lack of large-scale empirical studies that examine the localness of place names and their changes with geographic distance. In addition to enhancing our understanding of the coherence of geographic regions, such empirical studies are also significant for geographic information retrieval where they can inform computational models and improve the accuracy of place name disambiguation. In this work, we conduct an empirical study based on 112,071 POIs in seven US metropolitan areas extracted from an open Yelp dataset. We propose to adopt term frequency and inverse document frequency in geographic contexts to identify local terms used in POI names and to analyze their usages across different POI types. Our results show an uneven usage of local terms across POI types, which is highly consistent among different geographic regions. We also examine the decaying effect of POI name similarity with the increase of distance among POIs. While our analysis focuses on urban POI names, the presented methods can be generalized to other place types as well, such as mountain peaks and streets
POIReviewQA: A Semantically Enriched POI Retrieval and Question Answering Dataset
Many services that perform information retrieval for Points of Interest (POI)
utilize a Lucene-based setup with spatial filtering. While this type of system
is easy to implement it does not make use of semantics but relies on direct
word matches between a query and reviews leading to a loss in both precision
and recall. To study the challenging task of semantically enriching POIs from
unstructured data in order to support open-domain search and question answering
(QA), we introduce a new dataset POIReviewQA. It consists of 20k questions
(e.g."is this restaurant dog friendly?") for 1022 Yelp business types. For each
question we sampled 10 reviews, and annotated each sentence in the reviews
whether it answers the question and what the corresponding answer is. To test a
system's ability to understand the text we adopt an information retrieval
evaluation by ranking all the review sentences for a question based on the
likelihood that they answer this question. We build a Lucene-based baseline
model, which achieves 77.0% AUC and 48.8% MAP. A sentence embedding-based model
achieves 79.2% AUC and 41.8% MAP, indicating that the dataset presents a
challenging problem for future research by the GIR community. The result
technology can help exploit the thematic content of web documents and social
media for characterisation of locations
The semantics of similarity in geographic information retrieval
Similarity measures have a long tradition in fields such as information retrieval artificial intelligence and cognitive science. Within the last years these measures have been extended and reused to measure semantic similarity; i.e. for comparing meanings rather than syntactic differences. Various measures for spatial applications have been developed but a solid foundation for answering what they measure; how they are best applied in information retrieval; which role contextual information plays; and how similarity values or rankings should be interpreted is still missing. It is therefore difficult to decide which measure should be used for a particular application or to compare results from different similarity theories. Based on a review of existing similarity measures we introduce a framework to specify the semantics of similarity. We discuss similarity-based information retrieval paradigms as well as their implementation in web-based user interfaces for geographic information retrieval to demonstrate the applicability of the framework. Finally we formulate open challenges for similarity research
ISED: Constructing a high-resolution elevation road dataset from massive, low-quality in-situ observations derived from geosocial fitness tracking data
Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund.Gaining access to inexpensive, high-resolution, up-to-date, three-dimensional road network data is a top priority beyond research, as such data would fuel applications in industry, governments, and the broader public alike. Road network data are openly available via usergenerated content such as OpenStreetMap (OSM) but lack the resolution required for many tasks, e.g., emergency management. More importantly, however, few publicly available data offer information on elevation and slope. For most parts of the world, up-to-date digital elevation products with a resolution of less than 10 meters are a distant dream and, if available, those datasets have to be matched to the road network through an error-prone process. In this paper we present a radically different approach by deriving road network elevation data from massive amounts of in-situ observations extracted from user-contributed data from an online social fitness tracking application. While each individual observation may be of low-quality in terms of resolution and accuracy, taken together they form an accurate, high-resolution, up-to-date, three-dimensional road network that excels where other technologies such as LiDAR fail, e.g., in case of overpasses, overhangs, and so forth. In fact, the 1m spatial resolution dataset created in this research based on 350 million individual 3D location fixes has an RMSE of approximately 3.11m compared to a LiDAR-based ground-truth and can be used to enhance existing road network datasets where individual elevation fixes differ by up to 60m. In contrast, using interpolated data from the National Elevation Dataset (NED) results in 4.75m RMSE compared to the base line. We utilize Linked Data technologies to integrate the proposed high-resolution dataset with OpenStreetMap road geometries without requiring any changes to the OSM data model
Where you go is who you are -- A study on machine learning based semantic privacy attacks
Concerns about data privacy are omnipresent, given the increasing usage of
digital applications and their underlying business model that includes selling
user data. Location data is particularly sensitive since they allow us to infer
activity patterns and interests of users, e.g., by categorizing visited
locations based on nearby points of interest (POI). On top of that, machine
learning methods provide new powerful tools to interpret big data. In light of
these considerations, we raise the following question: What is the actual risk
that realistic, machine learning based privacy attacks can obtain meaningful
semantic information from raw location data, subject to inaccuracies in the
data? In response, we present a systematic analysis of two attack scenarios,
namely location categorization and user profiling. Experiments on the
Foursquare dataset and tracking data demonstrate the potential for abuse of
high-quality spatial information, leading to a significant privacy loss even
with location inaccuracy of up to 200m. With location obfuscation of more than
1 km, spatial information hardly adds any value, but a high privacy risk solely
from temporal information remains. The availability of public context data such
as POIs plays a key role in inference based on spatial information. Our
findings point out the risks of ever-growing databases of tracking data and
spatial context data, which policymakers should consider for privacy
regulations, and which could guide individuals in their personal location
protection measures
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