Getting Started

To get started with VOSviewer, you may want to take a look at some of the sources of information listed below.

Video

Share this page

VOSviewer manual

The VOSviewer manual provides detailed and up-to-date information on the functionality of VOSviewer. The manual can also be accessed using the Manual button in VOSviewer.

Open VOSviewer manual

 

VOSviewer book chapter

VOSviewer is discussed in detail in a recent book chapter. The chapter provides a tutorial in which the use of VOSviewer is demonstrated in a step-by-step manner. The chapter is based on VOSviewer version 1.5.5. Some of the improvements and extensions introduced in the most recent versions of VOSviewer are therefore not covered in the chapter. In addition to VOSviewer, the chapter also discusses the CitNetExplorer tool for visualizing and analyzing citation networks of publications.

Open VOSviewer book chapter

VOSviewer paper

VOSviewer was originally introduced in a paper published in Scientometrics in 2010. In the meantime, VOSviewer has been improved and extended in many ways, so the paper is not fully up-to-date anymore. However, it still provides a useful introduction into the main ideas underlying VOSviewer.

Open VOSviewer paper

AIDA bookletAIDA booklet

The AIDA booklet introduces diverse case studies on research positioning and trend identification. These case studies are relevant for PhD candidates, researchers, group leaders, and policy makers. Many of the case studies make use of VOSviewer.

Open AIDA booklet

Comments

Mandatory fields
  • Jackie Greatorex December 7th, 2021 3:21 pm
    HI
    does this work in a language other than English?
    Thanks
    Reply
  • Philip December 5th, 2021 12:44 am
    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.
    Reply
  • Philip December 4th, 2021 2:41 pm
    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?
    Reply
  • analytics December 4th, 2021 9:25 am
    Dear Sir/madame
    I would like to visualization a map by Wikipedia. Can you help me?
    Reply
  • Maria Calvo Uyarra December 4th, 2021 2:07 am
    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
    Reply
    • philip December 5th, 2021 8:21 am
      You have inadvertently included either Acropora or coral species in both columns. Use cntrl F to search each column for both terms until you figure out which keyword is duplicated. Then fix it so that neither of the terms is in both column A and B.
      My suggestion.
      PH
      Reply
  • giuseppe vito December 1st, 2021 1:12 pm
    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?
    Reply
    • Ludo Waltman December 1st, 2021 6:42 pm
      It is the number of co-occurrences of two terms, so the number of documents (i.e., lines in your corpus file) in which both terms occur.
      Reply
  • Katie December 1st, 2021 8:02 am
    _ ____ _____ _____ __ ____ _____ ________ _____ _ ____ _____ ________ __________, _ __ _________ ___________.
    ________ ___-__ _________ ___ _________ _ ________, ___-__ __ _____________
    _________, _ _____ ______ ___________
    _ __________ _ ______ __ ____, _______ __________ ___ _____.
    ___ ______________ _________ _ _________ _____________ _____ _________ ______ ____
    _____, _____ ___ __________ ________ ______ _ ________ _________ __________ ____________.
    _________ _______ ________ ______ _________ ________, __ _______ ____ __ _________ _______ _____.
    ___________ _____________ _
    _____ ______ _ ________ __ ______ ______,
    _ _____ ________, __ __ __________.
    Reply
  • Shahid Rasool November 29th, 2021 9:36 am
    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
    Reply
  • Shubham Singhania November 29th, 2021 8:11 am
    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
    Reply
  • Liuyong Ding November 29th, 2021 5:44 am
    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?
    Reply
  • 杨增增 November 28th, 2021 3:10 am
    I want to learn the VOSviewer.
    Reply
  • Manuel Vidal Jr November 27th, 2021 11:55 pm
    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!
    Reply
    • Ludo Waltman November 28th, 2021 5:31 pm
      Yes, this can be done using a so-called thesaurus file. Please see the VOSviewer manual for more information about thesaurus files.
      Reply
  • Paulo Nuno Vicente November 26th, 2021 3:33 pm
    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
    Reply
  • C Jimenea November 26th, 2021 6:50 am
    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?
    Reply
    • Ludo Waltman November 27th, 2021 4:21 am
      Unfortunately the functionality that we are able to provide in VOSviewer for creating maps based on RIS files is quite limited. In particular, VOSviewer is unable to create citation-based maps based on RIS files. While RIS files may contain reference data, this data doesn't have a standardized format. Therefore VOSviewer is unable to process the data.
      Reply
      • C Jimenea November 27th, 2021 4:36 am
        Okay. Thank you, again, for your quick response. And thank you for providing the research community with a very interesting tool.
        Reply
  • C Jimenea November 25th, 2021 5:58 pm
    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.
    Reply
    • Ludo Waltman November 26th, 2021 12:53 am
      I am afraid there is no easy way to accomplish this. The file formats used by Web of Science and Scopus are quite different, making it highly challenging to combine data from these two databases.
      Reply
  • Josie November 14th, 2021 8:01 pm
    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
    Reply
  • Racliffe Lai November 10th, 2021 9:16 am
    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.
    Reply
    • Ludo Waltman November 10th, 2021 2:33 pm
      To identify and merge related terms occurring in titles and abstracts of documents, my advice is to create a thesaurus file. See the VOSviewer manual for more information about thesaurus files.
      Reply
      • Racliffe Lai November 13th, 2021 11:06 am
        Thank you for your prompt reply!
        Reply
  • Sona Fathi November 6th, 2021 10:42 pm
    how can I export cluster items (items of each cluster separately)?
    Reply
    • Ludo Waltman November 7th, 2021 10:38 am
      You can save your map in a VOSviewer map file. This is a plain text file that can be opened in a spreadsheet program such as MS Excel. The information you need can be obtained from the map file.
      Reply
  • Julia Naranjo November 3rd, 2021 11:18 pm
    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?
    Reply
  • Peter November 3rd, 2021 1:33 am
    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.
    Reply
    • Peter November 3rd, 2021 3:37 am
      BTW, I'd read the post by Toshiyuki Hasumi below and checked the manual as well. But I'm still not too sure how to understand total link strength in keyword co-occurrence. Any further explanation/help is much appreciated.
      Reply
    • Josie November 11th, 2021 8:33 pm
      Hi Peter,
      I just did some thorough research on this and came up with the following explanation:
      Each link has a strength associated with it that refers to the number of publications in which the terms occur together. The total link strength of an item (keyword) is the sum of all of it's individual link's link strengths.
      For example, keyword A has 2 links, link to term B (strength 3) and link to term C (strength 4). The total link strength for keyword A is 7.
      Reply
      • Ludo Waltman November 11th, 2021 11:42 pm
        Thanks Josie, your interpretation of total link strength is indeed correct.
        Reply
        • Peter November 12th, 2021 1:38 am
          Hi Josie and Ludo,
          Many thanks for the explanation. I see what it means now. Much appreciated for the help!
          Reply
  • Sefika October 30th, 2021 10:06 pm
    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?
    Reply
    • Ludo Waltman October 31st, 2021 8:39 pm
      I don't think I fully understand your question. Could you let me know where you found the number of 1710 documents in the user interface of VOSviewer?
      Reply
      • Sefika October 31st, 2021 9:52 pm
        The number of the documents I exported from Scopus was 1864. I uploaded it to VV to create a citation-based map of countries and to analyze the geographic distribution of the publications & citations. The list of documents by country generated by VV where it asks to verify selected countries (just before the map) adds to 1710 documents and the map is based on 1710 documents.
        Reply
        • Ludo Waltman November 1st, 2021 9:35 am
          Thanks for clarifying. I think there's no reason to be concerned about this. Some countries probably have been filtered out (since VOSviewer by default includes only countries with a certain minimum number of documents). Also, there may be documents without affiliation/country data, so these documents cannot be used in a country-level analysis.
          Reply
  • irfani ahmad October 29th, 2021 4:47 pm
    I want to try it, hopefully it can be a solution to my problem
    Reply
  • Michael S Mendez October 26th, 2021 3:39 pm
    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!
    Reply
  • mr KIM October 12th, 2021 6:05 pm
    I try to visualize countries unfortunately this function is switched off and I could not press the "countries" button
    thank for advice
    Reply
  • Jong-Hwan Lee October 11th, 2021 11:58 pm
    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!
    Reply
  • Bi Chen October 10th, 2021 4:39 am
    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?
    Reply
  • manoranjan dash October 8th, 2021 5:55 pm
    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
    Reply
    • Ludo Waltman October 9th, 2021 11:03 pm
      When exporting data from Scopus, make sure to include all data elements, in particular the references.
      Reply
  • THEODORA VAGDATLI October 5th, 2021 7:01 pm
    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.
    Reply
  • George October 5th, 2021 12:15 am
    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.
    Reply
    • Ludo Waltman October 6th, 2021 1:08 pm
      VOSviewer takes an algorithmic approach to separate countries and organizations in affiliation strings in CSV files exported from Scopus. The algorithm makes use of the fact that the last part of an affiliation string typically refers to a country. Unfortunately, however, this doesn't always yield correct results, so in some cases the algorithm may fail to separate countries and organizations in a correct way. You may then consider the use of a thesaurus file to perform some further data cleaning (see the VOSviewer manual for more details).
      Reply
  • IMOLEAYO AWODELE October 4th, 2021 7:14 pm
    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
    Reply
  • Philip September 27th, 2021 1:16 pm
    In brief, as a user of VOSviewer hat are the value-added features of Cite Explorer?
    Philip
    Reply
  • Dung Vu September 27th, 2021 12:06 pm
    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.
    Reply
  • Antonis Pavlozas September 16th, 2021 6:00 pm
    I wanted to ask what is the difference of total strength link and the occurence that exist at the end of every network.
    Reply
  • Josephine Slaathaug September 10th, 2021 8:28 pm
    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
    Reply
  • Andy Yeung September 8th, 2021 8:58 am
    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
    Reply
    • Ludo Waltman September 9th, 2021 8:14 am
      Could it be that you have exported data for patents from the Lens instead of data for scholarly works?
      Reply
      • Andy Yeung September 10th, 2021 10:04 am
        I confirmed that I exported data from Scholarly works. And I am using Mac version of VOSviewer.
        Reply
        • Ludo Waltman October 6th, 2021 9:10 am
          Andy, are you sure your CSV file includes organization and coutry affiliation data? I don't think this data is included in CSV files exported from the Lens. (These files do include a 'source country' column, but this refers to the country of the journal.) Because CSV files exported from the Lens don't include organization and coutry affiliation data, VOSviewer is unable to create bibliographic coupling maps based on organizations and countries.
          Reply
          • Andy Yeung October 21st, 2021 4:30 am
            Now I understand... I was confused by 'source country' column. It is a pity that data from Lens is incomplete. I will then stick to WOS and Scopus. Thanks!
            Reply
    • George October 5th, 2021 11:39 am
      Same problem for me
      Reply
      • Ludo Waltman October 6th, 2021 9:12 am
        Please see my above response to Andy.
        Reply
  • Alexsander Canaparro September 5th, 2021 12:00 am
    Hi,
    Can i help me about this error "IOException reading: java.io.IOException: (line 164)
    Reply
  • Olugbenga Timo Oladinrin August 30th, 2021 3:18 pm
    How can I merge two or more keywords with the same meaning on plain text data downloaded from web of science?
    Reply
    • Ludo Waltman August 30th, 2021 8:06 pm
      This can be done using a so-called thesaurus file. See the VOSviewer manual for more information.
      Reply
      • Olugbenga Timo Oladinrin August 30th, 2021 10:32 pm
        Thank you for your swift response.
        The information on thesaurus file works with CSV/Excel file only. As Web of Science data are downloaded as plain text for compatibility with VOSviewer, the information on thesaurus file may not work.
        Any further suggestions?
        Reply
        • Ludo Waltman August 31st, 2021 12:03 am
          A thesaurus file can be either a CSV file or a TXT file. Both are plain text files. Excel files cannot be used as thesaurus file.
          Reply
  • Nazanin August 20th, 2021 12:11 am
    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
    Reply
    • Ludo Waltman August 20th, 2021 7:49 am
      Which data source did you use?
      Reply
  • ANG August 17th, 2021 11:12 am
    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!
    Reply
    • Ludo Waltman August 17th, 2021 1:24 pm
      Based on the information in your message, I am afraid I cannot say much about this. Feel free to send your data to vosviewer@cwts.leidenuniv.nl. I will then try to take a look at it.
      Reply
  • Lukas M August 15th, 2021 10:26 pm
    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!
    Reply
    • Ludo Waltman August 16th, 2021 12:25 am
      I am afraid there is no easy solution to your problem. In VOSviewer, a term in a term map must consists of nouns and adjectives only. Words such as 'and', 'of', and 'for' cannot be part of a term.
      Reply
  • Scott Rosas August 15th, 2021 4:23 am
    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
    Reply
    • Ludo Waltman August 16th, 2021 12:20 am
      There must be a label in your file that occurs in both columns (not necessarily in the same row). This is not allowed.
      Reply
  • Josephine Slaathaug August 10th, 2021 4:33 pm
    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?
    Reply
    • Josephine Slaathaug August 10th, 2021 4:53 pm
      A key part i forgot to mention in my first comment is that this is under the option "based on text data" for a co-occurrence map.
      I'm running into a different error for trying to create a map based on bibliographic data; which is "Multiple AU fields" but the way Web of Science exported the data left multiple lines with AU and then a co-author's name. What is a way around this to get vosviewer to accept multiple lines of AU or get web of science to export files with all authors listed on one line of code?
      Reply
  • Helena HG August 4th, 2021 10:05 pm
    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!
    Reply
    • Ludo Waltman August 8th, 2021 10:35 am
      This is indeed a bit confusing, but let me try to explain it. 'Citations' is the number of citations received by a document in Web of Science. 'Norm. Citations' is similar, but with a normalization to correct for the fact that older documents have had more time to receive citations than more recent documents. 'Links' is the number of documents in your network with which a given document has a citation link, either a citing link or a cited by link. Please note that 'Citations' and 'Norm. Citations' are statistics that are based on the entire Web of Science database, while 'Links' is based only on the documents included in your citation network.
      Reply
  • Josie Slaathaug August 4th, 2021 6:19 pm
    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!
    Reply
    • Ludo Waltman August 4th, 2021 7:23 pm
      Keywords can be author keywords or keywords assigned by the database that you are using (e.g., KeyWords Plus in Web of Science or MeSH keywords in PubMed). Depending on which database you are using, VOSviewer may enable you to choose one or the other (or both).
      It is also possible to create a co-occurrence map based on terms extracted from titles and abstracts of publications. This is called a term co-occurrence analysis rather than a keyword co-occurrence analysis.
      Reply
  • hasyim August 1st, 2021 12:21 am
    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,
    Reply
  • Poulomi July 22nd, 2021 3:42 pm
    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
    Reply
    • Ludo Waltman July 23rd, 2021 7:45 am
      VOSviewer offers the possibility to save a network in Pajek files and to then open the network in Pajek. However, I am not a regular user of Pajek, so my knowledge of Pajek is very limited. Therefore I am afraid I cannot offer any helpful advice in response to your questions. Sorry for that.
      I do want to note that VOSviewer doesn't provide support for combining data from multiple data sources, such as Web of Science and Scopus. Using data from multiple data sources in a single analysis is not possible.
      Reply
      • Silvia Dobre July 23rd, 2021 7:59 am
        Ohhh that's a pity (RE: multiple sources), As I worked on the REF submission of an UK HE institution for 3 years I could say that it was a great advantage to be able to use both WoS and Scopus extractions to check and improve the metadata of the outputs from the Internal Repository. Especially in the last months, when the WoS extraction was made quicker with the Excel option. Yes, the field order might be different, but the type of information is basically the same: Title, Year, DOI, Volume, Start Page, etc. So, I'm thinking if we "line up" the 2 extractions so that the fields and the data format matches we can, in theory, combine the data sources, then save the file as csv and upload to VOSviewer. I am very happy that I was able to secure a place for this autumn training - it will be a great opportunity to learn more. Many thanks
        Reply
        • Poulomi Chakraborty August 2nd, 2021 4:30 pm
          I have tried combining two sources of data (WOS & Scopus) into one RIS format after removing the duplicates, but in that case, when I upload the RIS file, the options Vosviewer provides are surprisingly limited to only co-occurrence of key-word analysis. No other options are available.
          If anybody knows how to combine both sources yet have all analysis options available, please let me know. Thank you.
          Reply
          • Burcu Durmaz September 14th, 2021 5:57 pm
            Dear Poulomi,
            I wonder if you have found an effective solution for this problem. I've tried different ways such as Endnote etc. but they didn't work. If you found, could you please share with me? Thank you.
            Reply
  • LUIS RODRIGUEZ July 20th, 2021 8:52 pm
    I was trying to do a map with vosviewer, but I couldnīt because appear a message
    Error while Reading file scopus.csv (line 252) incorrect numbre of columns
    Can you help me?
    Thanks
    Reply
    • Ludo Waltman July 20th, 2021 9:05 pm
      Please take a look at earlier discussions on this forum about Scopus CSV files. I think that will provide helpful information. Let me know if this doesn't solve your problem.
      Reply
      • Leandra September 6th, 2021 10:54 pm
        I am having the same problem. And couldnt find the earlier discussions. can you help me?
        Reply
        • Orlando Vazquez October 13th, 2021 5:25 pm
          I had the same problem, but I was able to solved it. I exported a csv file excluding the Funding details (number, acronym, sponsor, funding text) and Other information tabs (tradenames and manufacturers, accession numbers & chemicals, conference information). Note that from the Other information tabs, I only selected "Include references'. In doing so, I was able to create all the network visualizations that are available in VoS viewer for Scopus cvs files.
          Reply
  • Larysa July 18th, 2021 3:42 pm
    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
    Reply
    • Ludo Waltman July 19th, 2021 11:46 pm
      You need to make sure that each line in your thesaurus file consists of exactly two columns (separated by a tab). My advice is to use a spreadsheet program such as MS Excel to create the thesaurus file. Make sure there is no empty third column in the file. VOSviewer won't be able to read the file if some lines include an empty third column.
      Reply
  • Hari Babu July 18th, 2021 11:57 am
    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.
    Reply
    • Ludo Waltman July 19th, 2021 11:41 pm
      Are you using data from Web of Science or Scopus? When exporting data from Web of Science or Scopus, make sure that the references of documents are included in the export. By default they are not included, so you need to overrule the default settings and indicate that references should be included.
      Reply
  • Silvia Dobre July 14th, 2021 3:24 pm
    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
    Reply
    • Ludo Waltman July 15th, 2021 12:05 am
      I am not a SciVal user myself, so it is difficult for me to offer advice. However, I am not sure whether SciVal data can easily be converted to Scopus CSV data. VOSviewer will be able to process the CSV files only if they follow exactly the Scopus CSV format. Even very small deviations from this format may cause difficulties.
      Great to have you in our course later this year!
      Reply
Build on Applepie CMS by Waltman Development