Getting Started

HI
does this work in a language other than English?
Thanks

Two follow-up questions on the interpretation of metrics in author co-citation analysis.
1. If Author A has 3 different publications cited in Author X's document will that count has 3 citations in the co-citation table/list generated by VOSviewer, or only as 1?
2. The author co-citation table/list in VOSviewer shows that I have an author who has been cited 43 times in the reference lists of the documents in my database. When I click on the link between this author and another author close by, I find that the link has a strength 0f 1,806.
I don't understand how the link strength can be higher than the number of times the author has been cited in the reference lists. This is something that has puzzled me for several years, despite reading all of the information I can find about how to interpret link strength.
Please clarify.

Assume that I have an author co-citation map with a threshold of 25 citations, display of 75 authors, and four clusters on the map. Two scholars each have more than 25 citations (co) and have links to all four clusters. However, they are located far away from all other authors and clusters on the map. Moreover their affiliation is with a cluster located on the opposite corner of the map.
What is it about their co-citation pattern by other scholars that locates them as outliers at such a distance from all other authors on the map?

Dear Sir/madame
I would like to visualization a map by Wikipedia. Can you help me?

Thank you for the software! it is great.
I have a problem in trying to get my thesearus right. It indicates that "a label cannot be both in the LABEL column and in the REPLACE BY column. It provides me the line where the problem is found. So for example in my label coloum I have "Acropora" and my replace by says "coral species". Yet, it indicates that it is the same label. If i decide not to replace, it allows me to move forward, but it indicates that I have the same problem with another line. Could you indicate me where can be the problem?
Thank you
maria

Hi, Ludo, glad to find you again. In a map of a corpus file (without a score file) what is the meaning of the links between two terms?

_ ____ _____ _____ __ ____ _____ ________ _____ _ ____ _____ ________ __________, _ __ _________ ___________.
________ ___-__ _________ ___ _________ _ ________, ___-__ __ _____________
_________, _ _____ ______ ___________
_ __________ _ ______ __ ____, _______ __________ ___ _____.
___ ______________ _________ _ _________ _____________ _____ _________ ______ ____
_____, _____ ___ __________ ________ ______ _ ________ _________ __________ ____________.
_________ _______ ________ ______ _________ ________, __ _______ ____ __ _________ _______ _____.
___________ _____________ _
_____ ______ _ ________ __ ______ ______,
_ _____ ________, __ __ __________.

Dear Admin,
I want to extract data of Scopus database but when follow your tutorial that is link of www.webofknowledge.come but that is not going to open same website as you are shown in your instruction video. Kindly help me how I can extract data for using VOSviewer software.
Best,
Shahid Rasool

I am using Vos-viewer for Citation and Co-cittaion analysis, it is not shwoing the tab for citation and co-citation analysis.
Can someone Please help what could be the issue and how this can be resolved

What can vosviewer be used for in Java?
e.g.
"java -jar VOSviewer.jar -map MappingFileRes2.27_overlay.txt -overlay_visualization -max_label_length 0 -scale 0.5 -save_screenshot_emf cluster6.emf"
but, How do I get the parameters of vosviewer, such as -map or -overlay_visualization?

I want to learn the VOSviewer.

Hi, thank you for making this software! I have a question regarding co-occurrences; I am currently doing an analysis of genes studied for the past decades. For instance, in my analysis output, the keywords "ace" (angiotensin converting enzyme) and "ace gene" appear as separate entries with separate relevance scores. Is there a workaround in which I can combine these two entries with a single relevance score (because they are most likely talking about the same thing, that is, the ace gene)?
Thank you!

I have exported the RIS and EndNote files of a sample of 13 scientific articles that I would like to analyze. When using VOSViewer version 1.6.17, the option is only provided to analyze the "title" field and not, as I would like, the "title and abstract". Is there a setting that allows this? Thank you so much for this great tool and your support

Thank you for the very quick response!
I was actually trying different export file formats that WoS and Scopus both had. RIS is one such common format, but it only produced co-authorship and co-occurrence analyses, despite opting to export all details of each reference. And it doesn't matter if I only use the RIS file from Scopus, from WoS, or from both. However, if I use the bibliographic dabase files of WoS and Scopus, either provide options for the five types of analyses. Am I doing something wrong and/or is there a workaround for RIS to get the other three types of bibliographic data analyses?

Hello,
Is there a way to merge the exported results from WoS and Scopus into VOS? I have references that show up in one but not the other so I'd like to combine both.
Thank you.

Hello, I have two questions!
Is there a publication besides the manual that provides a concise summary of what relevance scores are based on for creating a keyword co-occurrence map?
I'm trying to decide whether creating a bibliographic or text map better suits the keyword co-occurrences, and am wondering how those determine keywords differently? Using the same datafile, the methods vary by about 200 keywords and vary widely in the number of terms that meet the minimum threshold. Wondering how the methods differ.
Thanks,
Josie

I am trying to use OpenRefine to curate the similar words. From the suggested manual, I have learnt how to do the curation in the column of keywords in a Web of Science file. However, I actually would like to include the information from abstract too.
Is it possible that I do the curation after VOS Viewer has identified the words for analysis, i.e. the list VOS Viewer displays after counting the occurrences. I noticed that I could export the list but do not know if there is a way to import it after the curation.
Thanks a lot.

how can I export cluster items (items of each cluster separately)?

Does vosViewer use first author, matching author, or all authors for ACA?
The bibliometric analyzes that use Bibliometrix (R) and Vosviewer at the same time, are they based on different information for the analysis of authors?

I conducted an author keyword co-occurrence analysis. I understand the 'occurrence' of an item refers to the frequency of the keyword that appears in the corpus. The 'link' of an item refers to the number of co-occurrence of that particular word to other words in the corpus. But I'm not quite sure how to interpret the 'total link strength' of a particular item. I checked the manual and online but still won't be able to find an answer for this. I would be much appreciated if you can give me a hand on this.

I have run the citation for countries for 1864 documents exported from Scopus. The results I get from VOSviewer gives me the distribution for 1710 documents. I tried with other exported documents and the result is the same - the number of documents I get from VOSviewer is less than the number exported. Is there any explanation for this?

I want to try it, hopefully it can be a solution to my problem

It's my first time watching a video about VOSviewer as I find bibliometric analysis fascinating. Thank you for creating this tool so all the curious souls in the world can have a tool to understand and present text data with ease.
I'm delighted also to know that the software is for free.
This is awesome!

I try to visualize countries unfortunately this function is switched off and I could not press the "countries" button
thank for advice

VOSviewer + CitNetExplorer
Quick question regarding using both tools: when I read your paper (van Eck and Waltman, Scientometrics, 2017), you showed a great utility of using both tools. However, I did not fully understand how you did to get Fig. 3 using VOSviewer visualization from the 22 clusters obtained from CitNetExplorer. I assumed that you'd performed the clustering using CitNetExplorer and then exported/input the resulting clusters to the VOSviewer, right?
In the Conclusion section of the paper, you described that "However, the combined use of the two software tools is somewhat laborious, and preparing the input data for VOSviewer based on the clustering results provided by CitNetExplorer is not entirely straightforward."
I wonder whether there is any procedure/steps for me to follow to perform the function you showed in this paper (mainly, clustering of individual publications using CitNetExplorer followed by keyword analysis/visualization in an aggregate level using VOSviewer).
I guess the procedure is something like: (1) export clustering results as some sort of network file) from the CitNetExplorer and (2) open the clustering results along with bibliographic files (with title and abstract) in VOSviewer to visualize/analyze keywords.
I believe knowing the procedure of how to do this will significantly enhance the utilities of both tools.
I am looking forward to having feedback, and thanks very much for developing these great tools!

When I analyze the Chinese database, I import the network generated by vosviewer into pajek and rearrange it. When I import vosviewer again, the Chinese code is garbled. How to solve?

I am not able to work on Bibilography coupling and co-citation with Scopus data .
This option is not being highlighted
How the problem can be solved

Good afternoon,
I would like to ask something about the usage of "thesaurus_file" during a VOSviewer visualization based on "text-data" and "title and abstract fields" extraction of knowledge.
I used the "thesaurus_file" for both ignoring some generic terms and replacing some other with something else.
I realized that the new map also lacked the terms I wanted to ignore and the terms I wanted to replace with another term.
Is there any explanation for this?
Or is there anything I can do about it?
Your answer would be valuable for my academic research into my field.
Thank you in advance.

How does Vosviewer seperate country and organization when the input is csv data from Scopus? My problem is that by my co-authorship map of countries i also see organizations.

Dear Ludo Waltman,
I was amazed at this wonderful tool you created. You just safe a soul and many more who will find out about this incredible software!
Reading through the comment box was superb as you took time out to provide answers to every query raised.
Thanks for doing this great job; attending to query and questions!
I just heard about the VOS yesterday, how do I get register for training on the usage?
Though someone mention in the comment box about tutorial clip.
Thank you

In brief, as a user of VOSviewer hat are the value-added features of Cite Explorer?
Philip

Good afternoon!
I thank you a lot for providing us a very helpful tool for bibliographic visualization. My question is that when I imported a thesaurus file for keyword co-occurrence visualization map, the program informed that "Error while reading VOSviewer thesaurus file (line 1): Column header is empty". I have created my thesaurus file in Excel, had columns' headers as "label" and "replace by" and saved it as a CSV or TXT file. Could you please tell me what can I do to deal with this error, if you do not mind? I thank you very much for your support.

I wanted to ask what is the difference of total strength link and the occurence that exist at the end of every network.

Good afternoon,
A few simpler questions about the resulting visualization output:
-What do the lines represent?
-How does the program determine which keywords to connect?
-When the maximum # of lines is adjusted, how does the software decide which lines to remove?
Thank you,
Josephine

Hi Prof Waltman,
I downloaded the latest version of 1.6.17 and downloaded data from Lens to try it out. I found that using Bibliographic data, Organizations and Countries were not among the available options for Co-authorship and Bibliographic coupling. I checked the csv file and these fields were present in the data. Any steps did I miss? Thank you for your help.
Best regards,
Andy

Hi,
Can i help me about this error "IOException reading: java.io.IOException: (line 164)

How can I merge two or more keywords with the same meaning on plain text data downloaded from web of science?

Hi,
Thank you for this free software. I want to use this software for my systematic literature review. When I installed it, I noticed that it just have Co-authorship and Co-occurrence in the Type of analysis part and just Authors in the UNIte of analysis part. I downloaded the latest version too.
I would be grateful if you, please let me know what I should do?
Many Thanks

Hi Ludo!
Thank you for providing this amazing software, free to use!
However, I have a problem in generating the citation mapping. We had obtained the data from WoS, followed the steps in generating the map, but for a highly-cited author, the total link strength is zero. This author is hence not shown properly in the citation mapping (i.e. very isolated).
Is there any workaround for this issue?
Thanks in advance!

Hi,
I'm trying to perform term co-occurrence maps of publications associated with "Six Sigma". For instance, I exported publications from Scopus with the term "Six Sigma" occurring either in the title or the keywords. Now, when I analyse both the titles and the abstracts for co-occurrent terms the most abundant term (that is "Six Sigma") is missing, I only find "Sigma". The same is true for very common terms like "Six Sigma methodology" which translates to "Sigma methodology" in the term findings. Terms like "Design for Six Sigma" or "Design of Experiment" don't show up at all, I think they translate to "Design", "Sigma" or "Experiment", which is not quite the same.
Can I somehow "teach" VOSviewer to include those terms or to even look after terms with more words even if their words are concatenated with words like "and", "of", "for"?
Thanks in advance!

Hello,
I am utilizing a thesaurus file for a co-author analysis and I get an error that states: A LABEL cannot be in both the LABEL column and the REPLACE BY COLUMN. I have set up the txt file according to the example provided. All those in each row of REPLACE BY column are different than the corresponding text in the LABEL column. Any insight as to what might be throwing the error code?
Thank you,
Scott Rosas

Good morning,
When attempting to make a co-occurrence map from a plain text Web of Science output, I keep getting "file is invalid" error messages about lines of my code. After doing some looking through and editing, I found that its always an error about this part of the code's format:
AU
AU
AU
DA
DO
IS
N1
########
so the au through the n1 reads fine but the numbers following the line with n1 don't read. Any advice on what this is/how to avoid this problem?

Greetings!
I am loving VOSviewer and I just had a quick question. In my bibliographic network with Web of Science data, I am using a "citation" analysis with "documents" as my unit of analysis. I do not really understand the options for "weights" in the visualization panel. The default is "Citations" but I also see "Links" and "Norm. Citations." Despite skimming the manual and book chapter I am still unsure the difference between these weights. Could you kindly explain to me what the differences are, and under which contexts I might be interested in one weight versus another? Or if this is an obvious question, I would instead welcome a good source to review. Thank you in advance for your assistance!

Forgive me if this is a basic question, but I'm wondering what data or information is used to generate the keywords to make occurrence maps. Are the keywords generated from title/abstract? Are they pulled from the search engine (WoS for example) or are they the author generated keywords?
Any help is appreciated!

Dear researchers/writers,
I am a researcher who just knows VOSviewer. I will look for a collaborator writer who is an expert VOSviewer for working together on paper in "tropical disease issues like malaria, dengue infection, also in COVID19 on a systematic literature review using Vosviewer.
If you any interested, please let me know.
Thank you for sharing your experience with this great application.
Best,

Dear Sir,
I am a PhD student and using Vosviewer for my paper on a systematic literature review on tourism using Scopus data. I also want to apply the main path analysis using Pajek and use the input data from Vosviewer. I am facing problems with making the input file, I couldn't find any useful tutorial or manual which shows how to exactly do this. I have tried extracting the network data (citation network) into 3 available pajek files .net, .clu and .vec and tried following the pajek tutorial of analysing main path, but there is no result. Can you please share how can I make input files from Vosviewer for this? Also how can extract the cluster data of any analysis or cluster data for pajek? Also, if I want to use both databases WOS and Scopus and then analyse all this what would be the procedure?
Also, when I analysis all the data which are not refined yet, I am not getting a great result. But when I have used a dataset after manually excluding the irrelevant papers, I could see a better result. Shy is that? Which data would be better to use?
Sorry for this long questions, but I really want to understand this and apply this in my paper.
Thank you.
Regards,
Poulomi Chakraborty

I was trying to do a map with vosviewer, but I couldn´t because appear a message
Error while Reading file scopus.csv (line 252) incorrect numbre of columns
Can you help me?
Thanks

I cannot generate a thesaurus file. I do it according to the sample, but the system still writes an error.
What's wrong :
label replace by
human humans
humans humans
learning organizations learning organization
learning organization learning organization

Hello Nees Jan van Eck and Ludo Waltman,
I am trying to analyse the citation and cocitation analysis. The bullets for citation, bibliographic coupling and Co-citation are disabled. Please help me to address this problem.

Dear Ludo and colleagues, first of all congratulations for developing this very useful tool, which I used before. Could I please ask if I could upload 285k Excel records extracted from SciVal which I will, of course, transform in Scopus-like csv file and split in smaller files (please indicate what is the recommended upper limit of the number of rows / file). Many thanks for your support and I'm looking forward to the Bibliometrics and Scientometrics for Research Evaluation CWTS training, booked for mid November. Kind regards, Silvia D