Turn a list of sources and their targets into a network with Nocodefunctions App (and visualize it in Gephi)
By Dr. Verónica Espinoza, 2022 / ✔Twitter @Verukita1 ✔LinkedIn Dra. Verónica Espinoza
¿What is Nocodefunctions tool?
Nocodefunctions is a free, no-registration web app for click-and-point data analysis. The long-term objective with nocodefunctions is to provide a free, user friendly, robust web app helping a variety of audiences to use common (but sophisticated) data analysis functions, offered in their best-in-class versions [1, 2].
Nocodefunctions was developed by Clément Levallois, a professor based in Paris, with a passion for extracting information from social media and networks. He has published studies in academic journals.
Find all the options offered by the Nocodefunctions in this story I wrote on Medium [3].
¿What is Gephi?
Gephi is a tool for data analysts and scientists keen to explore and understand graphs. Like Photoshop™ but for graph data, the user interacts with the representation, manipulate the structures, shapes and colors to reveal hidden patterns [4].
The goal is to help data analysts to make hypothesis, intuitively discover patterns, isolate structure singularities or faults during data sourcing. It is a complementary tool to traditional statistics, as visual thinking with interactive interfaces is now recognized to facilitate reasoning. This is a software for Exploratory Data Analysis, a paradigm appeared in the Visual Analytics field of research [4].
Find more about Gephi tool in this story I wrote on Medium [5].
💡Motivation of this tutorial
I have been a teacher for more than ten years and I have diverse information related to my students. Looking for a way to generate a network visualization with information of subjects that students share, I explored an interesting function that Nocodefunctions App integrates in which it is possible to “turn a list and their targets into a network based on how many targets they share”. In other words: 2 students are connected if they have taken at least one course in common. The more courses they share, the thicker their connection.
📖What will we review in this tutorial?
This tutorial has two parts: Part 1 describes how to use the Nocodefuntions App to convert a list and its targets into a network based on how much “targets” they share. Part 2 describes how to visualize the network file (generated in Part 1) in the Gephi tool.
File prepared for this tutorial and explanation of the data.
First, I prepared an excel file with the following information: Column A contains the name of the student (source), Column B contains the Subjects (targets) they are studying (separated by commas).
To convert this excel file into a network I used option 2 of the Nodecodefunctions, which is possible to turn a list and their targets into a network based on how many “targets” they share, as explained below.
🏁Lets start!
Part 1. Network preparation in Nocodefunctions tool
a) First, open the Nocodefunction App in the option Free tool to create networks from co-occurrences or lists [link] and choose Option 2: sources and targets to network.
b) Click Open your file and Choose your CSV or Excel file.
c) Click Upload
d) Click Read the data in the file (s)
e) If your data has headers, then select as shown, otherwise don’t select it.
f) Click on the column as the source, in this case the one of the names of the students and confirm the information by clicking on “yes”.
g) The following information will appear, now click on the download gexf file button (you can also view your results in Gephisto or VOSviewer, but in this tutorial we will focus on viewing the results in Gephi).
Let us see part 1 in action!
Part 2. Network visualization in Gephi.
h) Open your file in the Gephi tool.
i) Run Modularity to detect communities (statistics section). Color nodes by Modularity Class (appearance section) and Run ForceAtlas2 Layout.
j) Make other adjustments, for example, rank the size of the nodes by degree (or another attribute that you want). You can also adjust the size of the labels, assign other colors to the nodes, rotate or expand the graph, among others. Make the necessary adjustments to get the network you like it!
😃You can apply other layouts, colors or other statistics, this is just an example!
k) Finally, visualize your network in the Preview section and if you are already happy with the result, download it in one of the formats that Gephi offers, as shown.
👍Thanks for reading
😃My Twitter
REFERENCES
- Explore your data at a click [Internet]. Nocode functions. [cited Nov 9, 2022]. Available in: https://nocodefunctions.com/
- blog N functions-. Nocode functions is one year old! [Internet]. [cited 2023 Jan 6]. Available from: https://nocodefunctions.com/blog/nocodefunctions-is-one-year-old/
- Espinoza V. Nocode functions tool: explore your data at a click! [Internet]. Medium. 2023 [cited 2023 Jan 5]. Available from: https://medium.com/@vespinozag/nocode-functions-tool-explore-your-data-at-a-click-200389e99b61
- Bastian M., Heymann S., Jacomy M. (2009). Gephi: an open source software for exploring and manipulating networks. International AAAI Conference on Weblogs and Social Media.
- Espinoza V. What is Gephi? Meet this useful network analysis tool [Internet]. Medium. 2023 [cited 2023 Jan 5]. Available from: https://medium.com/@vespinozag/what-is-gephi-meet-this-useful-network-analysis-tool-628a1b42428c
