Google Scholar, OverLeaf, and Gephi Prof. Ralucca Gera, Applied Mathematics Dept. Naval Postgraduate School Monterey, California rgera@nps.edu Excellence Through Knowledge

Excellence Through Knowledge

Try it at www.overleaf.com and register using your NPS email ShareLaTeX Free: https://www.overleaf.com/ OverLeaf is a web-based real-time collaborative (like GoogleDocs) LaTeX editor (no need of LaTeX on your machine) Documentation: https://www.overleaf.com/learn Templates: https://www.overleaf.com/latex/templates Try it at www.overleaf.com and register using your NPS email

Try it using your NPS email! Synch it with the Dropbox and GitHub (the dropbox account must use the same email addressed use to create the overleaf account): Click Account on the upper right on the main site Account settings Log in Dropbox Integration

Google Scholar (https://scholar.google.com/)

Google Scholar’s goals It enables searches of scholarly literature (scholarly publications, abstracts, books…). Easy to use (same familiar search bar as Google, but results are limited to scholarly resources). Contains links to the article’s PDF, Postscript, HTML format. Easy to view key information about articles: “cited by”, “related articles” and so on. Easy to export citation to LaTeX that can be used for any research formatting style.

Historical background Google Scholar was released (in beta) in 2004 Not the first freely available citation database (CiteSeer, Scirus, etc) Not subject specific Many use it as a viable alternative to traditional citation databases such as Web of Science, since: Easy of use (free, no account needed) Extensive coverage of articles Encodes wide range of metrics about articles/authors However metrics are not perfect (data base is not complete, some duplications exist, algorithms used)

Features of Google Scholar Searches all scholarly literature from one convenient place Explores related works, citations, authors, and publications Locates the complete document through your library or on the web Keeps up with recent developments in any area of research Checks who's citing your publications, creates a public author profile (if you get an account) Source: http://scholar.google.com/scholar/about.html#about

How are documents ranked? “Google Scholar aims to rank documents the way researchers do, weighing the full text of each document, where it was published, who it was written by, as well as how often and how recently it has been cited in other scholarly literature.” Source: http://scholar.google.com/scholar/about.html#about

Practice for the research publication Try Google Scholar now!

Gephi Overview (https://gephi.org/)

Resources for Gephi: Overview and explanations of Gephi Gephi’s overview tutorial An introductory video to create data for Gephi and to use degree, closeness and betweeness (also posted on the website unde today’s lecture). Gephi’s overview of layouts Basic navigation

Layout choices (install plugins for more): Layouts Layout choices (install plugins for more): Force directed (repulsion) ones: Force Atalas 2 (It is focused on being useful to explore and get meaning for real data, and a good readability, slow) Yifan Hu (similar to FA2, fast, good for large graphs) Fruchterman-Reingold (The nodes are the mass particles and the edges are springs between the particles. The algorithms try to minimize the energy of this physical system. It has become a standard but remains very slow.) OpenOrd layout (good for communities) Not force directed: Expansion Geographic map with GeoLayout

Cannot use undo in Gephi SAVE Once you have a visualization that you like, save the network, so that the next time you open it looks the same Cannot use undo in Gephi When you run an analysis, save the network again with a different name for future references When you open part of a network on a new tab in Gephi, save that as well.

Preview Tab Click Preview next to the Data Laboratory, you might like that view of the network better: If you export, then this is what you export:

Ranking nodes based on a statistic Once you ran a statistic (say degree) => size/color the nodes based on the ran statistic. Under on the top left, choose Nodes and either size or color Depending on the version you run, you will see:

Filtering nodes based on a statistic Find Filters on the top right, next to Statistics Under topology, you can find the centralities Choose one, drag and drop it to the Queries Choose the bounds needed.

Take a screen shot using Snipping Tool, or Export Take a screen shot using Snipping Tool, or Export the visualized graph as SVG or PDF: Go to preview (fix if needed) Resize for large networks Click SVG (SVG is vectorial graphics like PDF so they scale to different sizes nicely)

Other statistics Average path length: under the statics module, right Computes the average of shortest paths between all pairs of nodes Result:

Try Gephi Now!

Back up slides - GoogleScholar

Use “Advanced Search”

Google Scholar – Advanced Search

Google scholar - Metrics

Google Scholar – Advanced Search

H-index of a scientist from wikipedia “a scholar with an index of h has published h papers each of which has been cited in other papers at least h times” . Source: https://en.wikipedia.org/wiki/H-index

Google Scholar Available Metrics The h-index of a publication is the largest number h such that at least h articles in that publication were cited at least h times each. For example, a publication with five articles cited by, respectively, 17, 9, 6, 3, and 2, has the h-index of 3. Source: http://scholar.google.com/intl/en-US/scholar/metrics.html#metrics

Google Scholar Available Metrics The h-core of a publication is a set of top cited h articles from the publication. These are the articles that the h-index is based on. For example, the publication above has the h-core with three articles, those cited by 17, 9, and 6 in the list 17, 9, 6, 3, and 2 with the h-index 3. Source: http://scholar.google.com/intl/en-US/scholar/metrics.html#metrics

Google Scholar Available Metrics The h-median of a publication is the median of the citation counts in its h-core. For the example before, the h-median of the publication was 9 (recall the references are 17, 9, 6, 3, and 2 times, of which17, 9, 6 are in the k-core). The h-median is a measure of the distribution of citations to the articles in the h-core. Source: http://scholar.google.com/intl/en-US/scholar/metrics.html#metrics

Google Scholar Available Metrics Finally, the h5-index, h5-core, and h5-median of a publication are, respectively, the h-index, h-core, and h-median of the articles that were published in the last five complete calendar years. Source: http://scholar.google.com/intl/en-US/scholar/metrics.html#metrics