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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 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

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
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 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
  - Leandra September 6th, 2021 10:54 pm
    
    I am having the same problem. And couldnt find the earlier discussions. can you help me?
    
    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
  - Lorena Rojas August 11th, 2021 7:35 pm
    
    Hi, I have the same issue, I download the data from Scopus
    
    Reply
    - Ludo Waltman August 11th, 2021 7:56 pm
      
      Unfortunately there are problems with the Scopus CSV export. As a workaround, my suggestion is to include only the essential data fields in the export and to leave out the other data fields. This usually solves the problem. However, it may require a bit of trial and error to find out which data fields are causing the problem and need to be excluded from the export.
      We are discussing these problems with the Scopus team. They are working on new export features for Scopus, which will hopefully solve these problems. The new export features are expected to become available in 2022 Q1.
      
      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
    - Saul VILLAMIZAR August 5th, 2021 4:36 pm
      
      THANKS! It worked
      
      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