Citation Map: Visualizing the Spread of Scientific Ideas Through Space and Time

Blog

Team Members: Yingjie Hu, Grant McKenzie, and Song Gao

With Citation Map, what can we do:
- Searching publications and their corresponding citations through keywords or author names.
- Geolocating publications using the first author’s institution.
- Mapping citation information all over the world and in different years.
- Discovering the top 10 authors who have cited your publications most frequently.
- Sharing publication and citation information through social media like Facebook, Twitter, and Google Plus.

If you are interested in our work, please see more at: Song Gao, Yingjie Hu, Krzysztof Janowicz, Grant McKenzie. A Spatiotemporal Scientometrics Framework for Exploring the Citation Impact of Publications and Scientists. In ACM SIGSPATIAL GIS 2013, Nov. 5-8, 2013, Orlando, FL, USA. DOI: 10.1145/2525314.2525368.

Introduction
We designed a Citation Map for the Robert Raskin Mashup Mapping competition. This web mapping application is a novel approach to visualize research topics, authors, publications, as well as their citation relations on a world map. By displaying the geographic distribution of research paper citations, this dynamic web map shows how a scientific idea spreads through space and time (i.e. How a scientific publication is accepted and cited by researchers in different countries over the years). This Citation Map also shows the researchers who have cited your papers most frequently, and where are these researchers.

Multiple data sources have been integrated in this Citation Map. The basemap data come from OpenStreetMap, styled by Cloudmade and served through the Leaflet Javascript Framework, while the information about publications, authors, and citations are sourced through Microsoft’s Academic Search. The publication data are dynamically accessed and “mashed” with the basemap on the fly instead of storing the data locally. While one paper may have several co-authors, the institution of the first author has been employed as the location of the publication.

To view the citations of a single paper, users can first enter some keywords or author names and a list of candidate publications will be displayed. Users can click on one of the presented publications, and watch the map automatically zoom to the location of the first author’s institution.


Fig. 1: Using the keywords ’citizen as sensors’ to search papers


Fig. 2: Zooming to the location of the first author’s institution (eg. Prof. Michael Goodchild at UC Santa Barbara)

Users can also click on each of the pushpins to see detailed information about the publications and authors.


Fig. 3: Detailed information of a paper

Users can then click the “Map Citations” button in the upper right corner to see how this paper is cited by researchers throughout the world. As the citations are being displayed, the Citation Map also calculates the top ten authors who have cited the paper most frequently, and automically draw lines to link these authors with the first researcher. In this way, users can see which researchers have strong interests in the paper.




Fig. 4: Mapping the geographic distribution of research paper citations(e.g. Prof. Michael Goodchild, Prof. Michael Batty, and Prof. Martin Raubal)


Fig. 5: The mapping of the paper "community structure in social and biological networks" shows a global influence

This Citation Map has a number of potential applications. It can help researchers discover possible collaborators on the other side of the globe, or remind academics of similar work being conducted in their own backyard. Additionally, it can help visualize the geographic distribution of a particular research topic and stimulate thinking on the relationship between a specific research topic and particular regions (i.e. Why a research topic is so popular in certain areas). It can even provide an alternative method to evaluate a researcher’s influence (e.g., Whether an author’s influence is global or restricted locally).

Motivation
The number of citations is an important criterion to measure the quality of a scientific publication. A large number of citations often indicates a wide acceptance of the idea proposed by the paper. Therefore, many academic search engines, such as Google Scholar, Microsoft Academic Search, and Arnetminer, have stored citation information in their database, and has provided links to the citations of a paper.
While some academic search engines have also provided an abstract map, in which the citation relations of the authors are weaved into a network, there is still no such a map that can show the geographic distribution of a paper’s citations. Mapping such geographic distributions can help discover citation distribution patterns which may not be detected by simply looking at the numbers. For example, a publication which have 15 citations throughout the world may have a higher influence than a paper with the same number of citations but limited to a single country. There could be many other interesting applications with this Citation Map, and therefore we choose this topic, hoping to visualize how scientific ideas spread through geographic space over the years.

Design principle
In order to locate each scientific publication, we employ the location of the institution of the first author. We choose the first author’s location because the first author is usually the one who got the original idea and who has contributed most to their work. Microsoft Academic Search has been chosen as the publication data source because it has more complete information about the authors compared with many other academic search engines, such as Google Scholar.
To make the publication and citation information standout, we used a light color for the background, darker color for the publication markers, and multiple colors for the lines which link the author with those who have cited his\her paper. We also repeat the basemap so that empty space will not be shown if the user zooms out the boundary of the map.
When a citation has been found, it will be automatically pinned on the map. The density of the icons can show a geographic pattern of the citations (i.e. in which areas that a research topic is most popular). A series of icons in gradual colors have been provided to differentiate the most recent citations (in dark green colors) and those in earlier years (in light green colors). The authors who most frequently cited the paper are also displayed, and are connected using colored lines.

The Citation Map web can be accessed from the URL http://stko-work.geog.ucsb.edu:8080/map