Semantically-Enriched Search Engine for Geoportals: A Case Study with ArcGIS Online
This work addresses the challenge of improving geospatial data reusability and knowledge discovery for users of geoportals, though it is incremental as it builds on existing query expansion techniques.
The paper tackled the problem of limited search intention understanding in geoportals like ArcGIS Online by proposing a semantic query expansion framework that enriches queries from geospatial and thematic perspectives, resulting in a significant performance improvement with over 3.0 increments in DCG@K metrics compared to a baseline.
Many geoportals such as ArcGIS Online are established with the goal of improving geospatial data reusability and achieving intelligent knowledge discovery. However, according to previous research, most of the existing geoportals adopt Lucene-based techniques to achieve their core search functionality, which has a limited ability to capture the user's search intentions. To better understand a user's search intention, query expansion can be used to enrich the user's query by adding semantically similar terms. In the context of geoportals and geographic information retrieval, we advocate the idea of semantically enriching a user's query from both geospatial and thematic perspectives. In the geospatial aspect, we propose to enrich a query by using both place partonomy and distance decay. In terms of the thematic aspect, concept expansion and embedding-based document similarity are used to infer the implicit information hidden in a user's query. This semantic query expansion 1 2 G. Mai et al. framework is implemented as a semantically-enriched search engine using ArcGIS Online as a case study. A benchmark dataset is constructed to evaluate the proposed framework. Our evaluation results show that the proposed semantic query expansion framework is very effective in capturing a user's search intention and significantly outperforms a well-established baseline-Lucene's practical scoring function-with more than 3.0 increments in DCG@K (K=3,5,10).