Getting Started

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

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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
  • 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
  • LUIS RODRIGUEZ July 20th, 2021 8:52 pm
    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
    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
  • 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
  • Esteban July 12th, 2021 8:02 pm
    Best regards,
    I hope you are doing well with your loved ones.
    I join the thanks given by several of the researchers for the development of this interesting and excellent tool.
    On the other hand, I request your kind collaboration with regard to the following:
    I have downloaded the data from the WoS and SCOPUS databases in the file extensions supported by the software; however, it generates an error that continues to persist that says: Error in line (xxx). The download of said data was successful.
    What is the reason for this situation? Is it due to Java, or to the update of the databases? ¿Which will be the solution?
    I will be attentive to your kind collaboration and attentive comments.
    Reply
    • Ludo Waltman July 14th, 2021 12:23 am
      Make sure not to combine data from Web of Science and Scopus. Combining data from these databases is not possible. If you have exported data from Scopus to a CSV file, you may have problems similar to those reported below by other VOSviewer users working with Scopus CSV files (e.g., Philip H on May 5).
      Reply
  • Oscar Herrera July 12th, 2021 9:05 am
    Scopus
    Reply
    • Ludo Waltman July 14th, 2021 12:10 am
      There are often problems with Scopus CSV files. It is usually possible to work around this by including in your CSV files only the most essential data elements. For more information, please see my response to Philip H. on May 5.
      Reply
  • Oscar Herrera July 12th, 2021 5:43 am
    I cannot get the .csv file to open on vosviewer ( Error while reading file..... IOException reading next record: java.io.IOexception: (line 182) invalid char between encapsulated token and delimiter" ). I have looked into the file at line 182 but can't see anything special about it. Any other options to solve this problem?
    Reply
    • Ludo Waltman July 12th, 2021 8:34 am
      Which data source are you using?
      Reply
  • giuseppe vito July 9th, 2021 6:17 pm
    Dear Ludo, the export function of Web of Science (both in the new version and in the classic one) no longer contains the "full record and cited references" option. Do you or someone from the blog have any suggestions? Thanks for your attention.
    Reply
    • Ludo Waltman July 9th, 2021 11:44 pm
      It's very disappointing that the new version of Web of Science has been launched without the 'Full Record and Cited References' export option. However, the option is still available in the classic version.
      Reply
      • Pascal July 10th, 2021 5:06 am
        Thanks, I am having the problem. But how to switch to the classic version. I just can't find a way to change between the two versions. Any advice?
        Reply
        • Ludo Waltman July 10th, 2021 7:32 am
          It also took me some effort to find out how to do this. You need to click 'Products' in the top-right of the Web of Science interface and you will then see an option for switching to the classic version.
          Reply
  • Urmila July 7th, 2021 1:04 pm
    If I have two CSV files downloaded from the Scopus database based on different timeframes. For the analysis, I want both in one CSV. How to combine it and use it?
    Reply
    • Ludo Waltman July 9th, 2021 4:55 pm
      You don't need to combine the files. You can provide multiple CSV files as input to VOSviewer at the same time.
      Reply
  • Toshiyuki Hasumi July 4th, 2021 7:30 am
    First, thank you for providing such a powerful software! I have been using it for quite some time and would like to ask how the link and total link strength are calculated. I can't seem to find any detailed information on this, especially when conducting bibliographic coupling analysis. Could you please elaborate and/or direct me to publications with a detailed explanation?
    Thank you!
    Reply
    • Ludo Waltman July 4th, 2021 8:24 am
      Some explanation is provided in Chapter 2 in the VOSviewer manual. Let me know if this explanation does not answer your question.
      Reply
      • Toshiyuki Hasumi July 4th, 2021 9:32 am
        Thank you for the prompt response!
        Would I be correct to say that:
        The number of link (edge) of Doc.A is the number of publications (Doc.B,C,D,etc) it shares references with. And the total link strength (edge weight) of Doc.A is the number of shared references (Ref.A,B,C,D,etc) it has with other publications?
        ie.
        DocA with link of 5 means that 5 documents share the same references, while
        DocA with total link strength of 10 means that 10 references are shared between them?
        Sorry for the trouble, and thank you again for your elaboration!
        Reply
        • Ludo Waltman July 4th, 2021 11:20 am
          Yes, that is correct. Importantly, if document A shares reference X with both document B and document C, this would count as two shared references, not just one.
          Reply
          • Toshiyuki Hasumi July 9th, 2021 1:52 am
            I would also like to ask, how country is determined in VOSviewer. Specifically, is it based on author's nationality (first author?/corresponding?), organization (ie. Tokyo Univ = Japan), or other metrics?
            Thank you again for your response!
            Reply
            • Ludo Waltman July 9th, 2021 4:52 pm
              This is based on affiliations reported by authors in their publications.
              Reply
  • Ernesto Tavoletti June 17th, 2021 7:02 pm
    Manual says on page 43 "For examples of thesaurus files, see the files thesaurus_authors.txt and thesaurus_terms.txt." But I cannot find these files as examples. Where are they?
    Reply
    • Ludo Waltman June 17th, 2021 9:56 pm
      They can be found in the ZIP files that you can download from https://www.vosviewer.com/download.
      Reply
  • imran khan June 17th, 2021 5:20 am
    Good way to extract data at a glance
    Reply
  • imran khan June 17th, 2021 5:14 am
    well
    Reply
  • imran khan June 17th, 2021 5:06 am
    well and good
    Reply
  • Thibault Léchopier June 15th, 2021 2:39 pm
    Hi,
    I started using VOSviewer a week ago now, and it's really great, but I saw the maps you're displaying on the Home page and I can't seem to figure out how to create such a country-based or university-based mapping.
    I am using the following types of files : .enw , .csv , or a.txt with a list of DOI. But VOSviewer only offers me to create maps about authorships, keywords, citations, or bibliography, which was useful, but I'd like to go further.
    Do you know what type of file I should provide to VOSviewer in order to be able to visualize links between countries or universities ? I have this information in my .csv file but it won't be displayed by VOSviewer.
    Thank you very much
    Reply
    • Thibault Léchopier June 15th, 2021 2:53 pm
      Edit : sorry I do not use csv files as they are not accepted by VOSviewer, I mixed up with another software, but my problem remains the same
      Reply
      • Thibault Léchopier June 15th, 2021 3:28 pm
        (edit : please ignore my first edit, sorry for spamming)
        Reply
    • Ludo Waltman June 15th, 2021 10:08 pm
      Co-authorship maps and citation-based maps of countries or organizations can be created based on data from data sources such as Web of Science, Scopus, Dimensions, Microsoft Academic, and various others. I should note that some of the maps shown on the VOSviewer website cannot easily be reproduced, because they require access to large amounts of data as well as significant preprocessing of the data.
      Reply
  • Phuong Nguyen June 8th, 2021 3:36 am
    I am using the co-occurence analysis and got stucked in this particular situations. In my data have 1 document that consist of repeated references (1 document being references for many times). Should i manually delete the identical references?
    Reply
    • Ludo Waltman June 8th, 2021 8:04 am
      What kind of analysis are you performing, based on what kind of data? If you are performing a co-occurrence analysis of terms or keywords, references normally play no role in the analysis.
      Reply
      • sello Pokane June 8th, 2021 3:02 pm
        yes, i want to perform co-occurence analysis of terms and keywords. But the problem is that "co-occurence" option is not active. i don't know what is the problem because i downloaded the software from this website.
        Reply
        • Ludo Waltman June 8th, 2021 5:48 pm
          Probably your data set doesn't include keywords. In the first step of the 'Create Map' wizard, my advice is to choose the option 'Create a map based on text data' instead of the option 'Create a map based on bibliographic data'. This should enable you to create a co-occurrence map of terms extracted from the titles and abstracts of the documents in your data set.
          Reply
          • sello Pokane June 9th, 2021 10:08 am
            thank very much for your assistance, and much appreciated.
            Reply
          • Valdet Hadri July 8th, 2021 10:34 am
            Is there any solution, that within the data set (maybe to save not only RIS file) to include only keywords???
            Reply
      • Phuong Nguyen June 8th, 2021 6:06 pm
        I am doing the co-citation analysis. That's why i think that i have to cleaned up the duplicated references for better result. The result of pre and post edit are widely different.
        Reply
      • Phuong Nguyen June 8th, 2021 6:23 pm
        I am sorry, my mistake, i am doing the co-citation analysis. Somehow one paper's reference has too many duplicated references (4-5 times) ended up building a round form cluster that consists of 8 items. After cleaning it, the circle vanish and only some of the paper are kept. Have i done the right thing?
        Reply
  • sello Pokane June 6th, 2021 10:11 pm
    i have downloaded the software but the co-occurence analysis is not active
    Reply
  • Sama May 31st, 2021 2:55 pm
    Hi
    How to merge several small clusters into one cluster?
    I appreciate your consideration
    Reply
    • Ludo Waltman May 31st, 2021 5:25 pm
      You can save your map in a VOSviewer map file and then edit this map file in a spreadsheet program such as MS Excel. By changing the values in the 'cluster' column, it is possible to merge clusters.
      Reply
  • Osman Issah May 26th, 2021 11:52 am
    Please, do I need permission before I can use Vosviewer visualizations and maps in my work/article?
    Reply
    • Ludo Waltman May 26th, 2021 1:04 pm
      You don't need any permission. Please feel free to use the visualizations in any way you want.
      Reply
  • Arun Saxena May 25th, 2021 9:13 pm
    Hi
    I am importing the Dimension CSV files. I do not find the co-occurrence of keyword option in the menu. Is this not available for the Dimension database?
    Thx
    Reply
    • Ludo Waltman May 25th, 2021 9:50 pm
      Indeed this option is not available for Dimensions data. Dimensions doesn't provide keywords.
      Reply
  • Christine Brodeur May 25th, 2021 7:58 pm
    Hi. I am used to use VosViewer with Web of Science data. I just tried to use it with an export from Dimensions, but when I am in VosViewer, at the step to upload the .csv, I get the message "Error while reading Dimension file "Tite of my file" : Index 0, Size 0". I read your manual, and looked at an online tutorial, so I think I exported correctly from Dimension (choosing Export for bibliographic mapping). Are there some manipulations that needs to be done with that csv file before uploading it in VosViewer?
    I also made sure I have the latest version of VosViewer (1.6.16)
    Thank you very much.
    Reply
    • Mathias June 9th, 2021 2:33 pm
      Hi Christine,
      I had the very same problem.
      In my case the solution was to edit the file and replace a carriage return in the query on first line of the file.
      I think the query can only be in first line.
      Bw Mathias
      Reply
  • Caroline May 25th, 2021 5:42 pm
    Hello,
    Thank you for developing this great tool! I am finding it super useful.
    I am working with a bibliographic datafile of 2415 publications exported from Scopus. For the co-authorship, citation and bibliographic coupling networks the "authors" option is not available. Is that a general problem with Scopus data? Or is there something I can do for the authors to be recognised (by name or ID number)?
    Reply
    • Caroline May 25th, 2021 10:35 pm
      My apologies. The issue is solved. (At some point, during editing and merging different files, the column name had changed.)
      Reply
  • Ushna Asif May 25th, 2021 3:38 pm
    Hi there,
    I have installed the latest version today but it is not activating following options while going for analysis:
    1. Citation
    2. Co-citation
    3. Bibliographic coupling
    I'm using scopus dataset with 890 data in CVS format..
    Plz reply fast
    Reply
    • Ludo Waltman May 25th, 2021 8:26 pm
      Please see my response below to a question by Anil Kumar on April 8.
      Reply
      • Swarup May 29th, 2021 2:26 pm
        I cannot find your response to A Kumar. Can you please give the solution again?
        Reply
        • Ludo Waltman May 29th, 2021 5:40 pm
          When exporting data from Scopus to a CSV file, the reference lists of publications are by default not included. VOSviewer then cannot create citation-based maps. When exporting data from Scopus, you need to make sure that the reference lists of publications are included. There is an option in Scopus to manually selected the data elements to be included in the exported data.
          Reply
  • Jun May 23rd, 2021 5:36 pm
    Hi,
    In the Co-occurrence map for keywords, it seems that the link strength between two keywords denotes the number of co-occurrence between these two words. In this case, what does the distance between these two words stands for? I have seen cases where two keywords have higher link strength are further away than those with lower link strength.
    Thanks a lot!
    Reply
    • Ludo Waltman May 24th, 2021 7:46 am
      The proximity of two keywords approximately represents the number of co-occurrences of the keywords, by default normalized using the association strength measure. The association strength measure corrects for the fact that keywords that occur in a large number of documents are more likely to co-occur than keywords that occur in just a limited number of documents.
      Reply
  • Joydip Barmam May 21st, 2021 8:29 pm
    Hi . Is it possible to make csv file manually for network visualization in VOSviewer. I don't have access Scopus, web of science . So I want to make csv file manually for network visualization in VOSviewer
    Reply
    • Ludo Waltman May 22nd, 2021 9:49 am
      You have the possibility to manually create a VOSviewer map file and VOSviewer network file. These file formats are documented in the VOSviewer manual. However, if you don't have access to Scopus and Web of Science, you may also consider the use of free alternatives. VOSviewer provides support for Dimensions, which is freely accessible. VOSviewer can also be used to query Microsoft Academic through its API. This is free as well.
      Reply
  • Nidhi May 21st, 2021 7:34 am
    Hi
    I am making a graph on co authorship(authors), like docs of author is 5 or citation 5, the link strength of an author is the highest like 533, its citation is also 33, docs also 700, and it is also shown in the exported list, the problem is this that it's not visualizing in the map or not even in the items list or clusters. Any suggestion
    Reply
  • Sama May 20th, 2021 5:47 pm
    Hi
    I have creating the thesaurus while I entered the terms according to the PabMed MESH database and there is an error for the line that does not exist. The number of terms is 81, but the error is for the line 82. What does it mean?
    (The primary output is from PabMad)
    Thanks
    Reply
  • sama May 14th, 2021 1:15 pm
    Hi
    Please send me a sample thesaurus to recall in Notepad or WordPad or Excel format. My files give an error. The error message is also about the header.
    Thanks
    Reply
    • Ludo Waltman May 14th, 2021 2:17 pm
      When you download VOSviewer from this website, sample files will be included in your download.
      Reply
      • sama May 14th, 2021 5:52 pm
        Thanks
        Reply
  • shubham singhania May 13th, 2021 1:24 am
    My Citation analysis, bibliographic coupling and co-citation tabs are not working the other analysis tabs are working. What is the issue can someone help me in this regard.
    Reply
    • Ludo Waltman May 13th, 2021 9:30 am
      What kind of data are you providing as input to VOSviewer? What is the data source you are using?
      Reply
  • Philip H. May 5th, 2021 9:23 am
    I have used VOSviewer in around 50 different studies using Scopus data (exclusively).
    Now, for the first time, I got an error message when trying to load the data file: "Error while reading Scopus file...(line 91): incorrect number of columns.
    I have tried numerous solutions including changing the CSV export conditions (e.g., no funding options etc.), restarting VOSviewer, and downloading fresh data files from Scopus. I've looked into the file at line 91 but can't see anything special about it. Any other options to consider?
    Reply
    • Ludo Waltman May 5th, 2021 9:30 pm
      In my experience these problems are due to small mistakes in the format of CSV files exported from Scopus. Unfortunately there is no easy solution. My recommendation is to select only the most essential data fields (e.g., authors, source, publication year, etc.) for the CSV export. This will hopefully solve the problem. You could then one by one add additional data fields to the CSV export. At some point you will find out which data field is causing the problem.
      Reply
    • somayeh May 16th, 2021 10:57 am
      hi!
      Do not combine files, Enter them separately
      I used this solution for web of science data
      Reply
    • Elias Olivares-Benitez June 30th, 2021 2:13 am
      I eliminated the "Funding details" since the export operations, and then the csv file could be read in VOSViewer.
      Reply
      • Maria del Mar Esponda Bernal July 26th, 2021 1:40 am
        It's true! something in the "Funding details" produces the error
        Reply
  • Riger Huerlandis May 4th, 2021 6:50 am
    In co-occurrence analysis, what is the minimum number of occurrences of a keyword means? Is that means, I choose 10 means the keyword needs to appear at least on 10 documents? Thanks
    Reply
    • Ludo Waltman May 4th, 2021 8:34 am
      Yes, that's correct.
      Reply
  • Meg Cross April 28th, 2021 4:57 pm
    Hello!
    I am looking for some information on how the clusters are made/determined. I have looked through the manual and read through how the clusters are expressed, but how are submissions actually sorted?
    Reply
  • Maria Luisa Lode April 27th, 2021 11:50 am
    The tool is very helpful, thanks! I have a problem with exporting the data that is visualised to a csv file for excel. Using a windows system, it can be retrieved before the visualization when the table pops up but using a Mac, I don't see this option. How can I export for e.g., the resulting cluster data using a Mac? Thank you.
    Reply
    • Ludo Waltman April 27th, 2021 12:33 pm
      In principle VOSviewer should behave identically on WIndows and Mac systems. In your case, it seems you need to use the 'Save' button on the 'File' tab to obtain the cluster data. This button should be available regardless of the operating system you are using.
      Reply
  • Aboagye April 26th, 2021 10:36 am
    Please I have downloaded VOSviewer, when I try to access it I get this feedback
    Error while reading Web of Science file 'savedrecs (2).txt' (line 31): Incorrect number of columns
    Please what do I do now?
    Reply
  • Maryam Alefpour April 21st, 2021 3:04 pm
    Hi,
    I would be appreciated if you explained how could I add year in last report.
    Thanks,
    Reply
  • Aynul April 21st, 2021 10:13 am
    Dear sir,
    I have now installed the latest version today but it is not activating following options while going for analysis:
    1. Citation
    2. Co-citation
    3. Bibliographic coupling
    Waiting for your suggestions.
    Reply
    • MD AYNUL HOQUE April 21st, 2021 6:06 pm
      Sorry, I found the solution. sorry for bothering you.
      Reply
    • shubham singhania May 13th, 2021 1:27 am
      Hello Aynul,
      I am facing the same issue as you. Can you please tell me how to resolve the same. Looking forward to your help.
      Reply
  • Prokriti Mukherji April 21st, 2021 8:52 am
    Hi,
    I am a lecture at King’s College London and I am using Vosviwer for the first time. I am looking to map/ link who published with whom and how much- sort of network of authors, from where I coudl hopefully pull out he netwokrs of the most published authors.
    I have a file in csv format with Title of paper, and columns with Author1, Author 2etc..
    I tried uploading this file but get multiple errors the main ones:
    1. When the title of paper remains in the file it just will not take it
    Else one time it said number of columns should be greater than number of lines
    My file has 1500 rows and 10 columns – does that mean I need to create 1500 columns ( the maximum authors we have on any one paper is 10)
    2. Line 3 unique ID (line three has two authors who have collaborate don many papers)- this is the Most common error I have been getting.
    I tried putting none31 in line 2 and none32 in row 3 so that the two rows would not be exactly alike but that did not work.
    Is there a simple way to upload a such a csv and get a network of authors mapped out?
    Would appreciate any help you can provide. Happy toc all and chat or do an MS teams call.
    Thank you in advance fro your help.
    Please a snapshot of the file below - sorry the formating is not okay but it is from a csv file.

    Title Author-Name-1 Author-Name-2 Author-Name-3..
    Measuring Consumer Interactivity in Response to Campaigns Coupling Mobile and Television Media ROBERTDAVIS LASZLOSAJTOS
    Reply
    • Ludo Waltman April 21st, 2021 9:16 am
      You need to provide your data to VOSviewer in a format that can be processed by the software. The best option seems to be to provide your data to VOSviewer in a VOSviewer network file (possibly combined with a VOSviewer map file). This would mean that you need to restructure your data so that it has the appropriate format for a VOSviewer network file. Please see the VOSviewer manual for more information about this format.
      Reply
  • Philip H. April 20th, 2021 10:49 am
    Hi
    I have created many thesaurus files but am encountering a strange problem with the most recent one. The file filters correctly for all analyses EXCEPT author citation analysis. For example, when I run author co-citation analysis the author names are correctly replaced with the alternate form. Keywords and countries are also replaced correctly.
    Any idea why that would happen?
    Philip
    Reply
    • Ludo Waltman April 20th, 2021 3:17 pm
      Make sure to write author names exactly in the format used by the database that you are working with (e.g., full first names or only initials, initials with or without periods, first names before last names or first names after last names, etc.).
      Please note that, depending on the database that you are working with, co-citation analysis may use a different format for author names (i.e., the format used in the reference lists of publications).
      Reply
      • Philip H. April 26th, 2021 12:44 pm
        Amazingly, yes that was the case. I've analyzed more than 50 Scopus files with VV. This was the first where author names had no commas in the citation analysis.
        Thanks.
        Philip
        Reply
  • Selma April 20th, 2021 10:22 am
    Hi,
    thank you so much for offering free of charge VOS viewer, it is amazing progress compared to some other previous softwares. I kindly ask you for your help, with mapping collaborators on a geographic map (Case 21 in AIDA booklet).
    Namely, I tried to understand how to add extra nodes that represent country boarders but have not been successful. Can you please explain me how to do that and where exactly to find instruction?
    Thank you.
    Reply
    • Ludo Waltman April 20th, 2021 2:33 pm
      I am afraid that detailed instructions are not available. As an alternative, you may consider using the NETSCITY tool. See https://www.irit.fr/netscity/prod/intro/.
      Reply
  • Zheng April 18th, 2021 3:51 pm
    Hi, I want to use VOSviewer to make a term co-occurrence map, but I found that the Chinese abstracts in the RIS file I imported cannot be recognized, and only a few English words can be subsumed in it. I have not found any information about Chinese abstracts on the Internet. So I am sorry to bother you, is it because Chinese is not supported? Thank you.
    Reply
    • Ludo Waltman April 18th, 2021 4:54 pm
      VOSviewer is only able to process English-language text. You could consider creating a machine translation of your abstracts from Chinese to English, and to provide the translated abstracts as input to VOSviewer.
      Reply
      • Zheng April 19th, 2021 5:12 am
        Thank you for your reply. I will try to translate it into English for analysis. Thanks!
        Reply
  • Philip H. April 18th, 2021 11:56 am
    We created a list in Scopus and downloaded as CSV. We did not open the csv file or change it in any way.
    We opened VOSviewer and loaded the file. However, the only analysis options that appear are Co-author and Co-occurrence.
    Why would that happen?
    Reply
    • Ludo Waltman April 18th, 2021 1:08 pm
      Please see my response below to a question by Anil Kumar on April 8.
      Reply
    • Philip H. April 18th, 2021 1:46 pm
      Sorry but i don't see any posts on April 8. There is an A Kumar in March but different question. Sorry for the inconvenience.
      Philip
      Reply
      • Ludo Waltman April 18th, 2021 4:50 pm
        The question by Anil Kumar can be found using the search feature in your browser. It's a response to an earlier conversation in January.
        Reply
  • Miyuki Maezawa April 16th, 2021 6:25 am
    Hi,
    I'm trying to create a map using a CSV file which I downloaded from Scopus. But an error message "Error while reading Scopus file 'scopus.csv';-1. I tried to download and make another new file in several times. What is the meaning of "-1" in the error message ? How can I resolve this ?
    Thank you.
    Reply
  • Santiago April 16th, 2021 3:31 am
    I'm having a problem and is that when I try to put a thesaurus to mi file, I follow all the steps that the manual said, but when I'll try to put it, VOSviewer says that the header of the first line is empty, and it is not
    Reply
    • matt April 29th, 2021 1:17 am
      Same here.
      Reply
  • Alba April 14th, 2021 5:44 pm
    Hi!
    I'm trying to create a map from PubMed. I've exported them like file with Medline format. Once I'm trying to open them in VOSviewer it says ¡ : "Error while reading PubMed file `pmc_results.txt` (line 2530): Multiple DP fields".
    And I have no idea about what I should do. Please, could you help me?
    I've used the software in the past and I have never had this problem.
    Thanks in advance.
    Reply
  • Bin Chen April 14th, 2021 7:09 am
    Hi, I am importing a pajek .net file into VOSviewer, but it says "error: all items have same coordinates." How should I fix this?
    Reply
  • Samantha April 11th, 2021 5:20 pm
    Hello there,
    I have a meta data exported from Web of Science, I wanted to analyze author bibliographic coupling, but unfortunately, some of the authors' name have written differently and they are counted twice or more and they got different scores.
    exp: Boje, d. or Boje d. m. or Boje, dm.
    so, the result is not valid, is there any way to have more accurate result?
    Many thanks.
    Reply
    • Ludo Waltman April 11th, 2021 7:14 pm
      To correct inconsistencies in author names, my advice is to create a thesaurus file and to provide this file as input to VOSviewer. See the VOSviewer manual for more information about thesaurus files.
      Reply
  • Ma In April 5th, 2021 9:38 pm
    Dear Ness and Ludo,
    Thanks for the wonderful demonstration on the YouTube. I tried to install the VOSviewer in my mac catalina. But the VOCviewer file opens but very soon closes by itself without any warning or such thing. I downloaded the latest Java and tried to use the tutorial you have provided for MAC users. But I did not get the settings/ open any way option at all.. Please let me know how I can install the VOSviewer.
    Thanks,
    M
    Reply
    • FAMC April 24th, 2021 5:51 am
      I may have a similar problem on MacOS Big Sur (11.2.3). When I point the file finder to the files (it does not see any files on the system, btw, only folders); rather when I input its local URL, the app does not see the file. I do have the latest Java. Should the app be in Mac's app folder? Should the data files be in the VOSviewer app folder or elsewhere? I could not find installation instructions on this in the tutorials or the manual, or maybe I missed them. It's so frustrating, because I love the idea of this application and could really use it for my doctoral studies. Thanks for any help one can provide to us Mac users. It would be great appreciated. (I have already provided system permissions to open and use the app.)
      F.A.
      Reply
  • Philip H. April 2nd, 2021 9:39 am
    I am reviewing a ms for publication and the author has applied journal co-citation
    network analysis, author co-citation network analysis, and bibliometric coupling to a database consisting of only 54 journal articles. It is my understanding from discussions on this Board that this is well below the necessary threshold for obtaining valid results through these bibliometric analyses.
    Am I correct, and are there any conditions that would make the application of these analyses to such a small viable?
    Thanks.
    Reply
    • Ludo Waltman April 2nd, 2021 10:02 am
      My view on this issue is that from a validity point of view there is no need to have a certain minimum number of articles. An analysis based on a small number of articles is not necessarily invalid. On the other hand, from a usefulness point of view, the value of an analysis based on a small number of articles may be quite limited. VOSviewer visualizations tend to be more useful when working with larger numbers of articles.
      Note also that a co-citation analysis based on a database consisting of 54 articles is likely to be more interesting than a bibliographic coupling analysis based on such a database. The bibliographic coupling analysis will be focused on the articles contained in the database, while the co-citation analysis will be focused on the references in these articles. This means that the co-citation analysis will probably cover a larger number of items (e.g., documents, authors, or journals) than the bibliographic coupling analysis.
      Reply
  • MICHAEL MCDONALD April 1st, 2021 4:09 am
    Hi,
    I have built a reference list based on a search on ProQuest, scanned / culled using Research Scanner with the selected references saved into an EndNote X9 database. I would like to use the EndNote output to run through VOSviewer. The output formats available are .txt and .enl files which I have not been able to make work. Unfortunately VOSviewer seems to be looking for .enw formats or .txt files in different formats from EndNote. Can you confirm that this is the case or point out what I am not doing correctly?
    Kind regards
    Reply
    • Ludo Waltman April 1st, 2021 10:35 am
      Unfortunately VOSviewer indeed does not support the ENL file format, but only the older ENW file format. The RIS file format may offer an alternative way to provide data as input to VOSviewer.
      Reply
      • MICHAEL MCDONALD April 2nd, 2021 8:19 am
        Hi Ludo,
        Thank you for your reply. Sorry to hear that VOSviewer does not support the newer EndNote file format. In suggesting using a RIS file format, are you suggesting that there should be a RIS file for each reference loaded into VOSviewer?
        Cheers
        Reply
        • Ludo Waltman April 2nd, 2021 9:53 am
          A single RIS file may contain data for multiple references.
          Reply
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