Impact factors of GIScience journals continue to increase in 2016

I am not a particular fan of the journal impact factor (IF): it is obsolete, it is susceptible to manipulation, and it does not guarantee quality. Furthermore, the distribution of citations within the same journal is usually highly skewed, which makes it inappropriate to talk about arithmetic means (on which IF is based). Even some editors of journals with a high IF denounce it openly.

Having said that, it’s hard to deny its importance in academia. For instance, in some countries it conditions promotions and the allocation of government funding.

For starters: the impact factor is a measure of citability of recently published papers in a journal. It is supposed to quantify the influence, reputation, and prestige of a journal; and everything is gauged and consolidated in a single number. The IF of a journal is calculated yearly as the number of references made to all papers published in the journal in the two preceding years, divided by their number (resulting in the yearly average of citedness of recent papers). For instance, the impact factor in 2015 of a journal is calculated as the ratio of cites in 2015 to papers published in 2013 and 2014, and the number of papers published in 2013 and 2014. For example, the journal Housing Theory & Society had published 42 papers in 2013 and 2014. In 2015 there were 43 cites to these 42 papers, as indexed by Thomson Reuters, resulting in an impact factor of 1.024. This also means that papers published before 2013 do not count. The same goes for papers published in 2015 (so a citation from a 2015 paper to a 2015 paper doesn’t count, nor ever will, oddly enough). Finally, not all journals have an IF – only those that are considered influential and of high quality by Thomson Reuters.

The IFs are announced yearly by Thomson Reuters in the Journal Citation Reports. The impact factors for 2015 have just been announced in the 2016 Journal Citation Reports. You can check them here if your institution has a subscription.

As I did last year, I checked the new IFs for the 19 journals that I consider relevant to people in GIScience. The list is composed from my scientometric paper published in IJGIS earlier this year (with the exception of JOSIS – Journal of Spatial Information Science, because it is not yet indexed by Thomson Reuters). For an extended list of journals please see the page compiled by my group.

The results are presented in the table below, also with the IFs in 2013 and 2014:


Generally the IFs continue to rise, as it was the case last year. On average, the IFs grew 16.5%.

The impact of 5 out of 18 journals has dropped: PFG‘s IF shrank by 24% (highest in relative terms), and IJDE’s by 0.5 (highest in absolute terms).

Cartography and Geographic Information Science is a clear winner, as its IF continues to grow substantially – from 0.5 to 2.2 in just two years.

While some journals experienced a considerable boost, in the previous edition their IF plummeted. See the case of GeoInformatica: 1.288 in 2013, down to 0.745 in 2014, and up by 42% to 1.061 in 2015. A substantial increase, but still lower than what it had two years ago.

One news is that the ISPRS International Journal of Geo-Information (IJGI), the Open Access journal published by MDPI got its IF (0.651) for the first time.

For some journals it paid off to deliberately delay paginating papers to boost the impact factor. There are some quintessential cases of holding papers without pagination for a long time, like Transactions in GIS:

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For IJDE that was not so lucrative: despite that the journal holds papers for long, its IF dropped. I wonder how much further it would drop if they didn’t employ such methods.

In total, the sum of all IFs continued to increase:


This might indicate that GIScience papers are recently attaining an increased reach outside the field. The results also show that IFs can be quite dynamic: IFs really go up and down, and in just one year their difference can be substantial, as for a third of journals (6/18) the IF changed by more than 30%.

Despite the general aversion to the IF, and its flaws, it’s certainly good news that GIScience papers continue to get more attention.

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GYSS 2016 in Singapore

I’ve had the privilege of attending the Global Young Scientists Summit (GYSS) 2016 hosted by the Singapore University of Technology and Design (SUTD). GYSS is a one-week yearly multidisciplinary gathering of young scientists and researchers from all over the world, with eminent international science and technology leaders. The speakers are recipients of the Nobel Prize, Fields Medal, Millennium Technology Prize, Turing Award and IEEE Medal of Honour. So all very prominent, accomplished, and inspiring scientists. Besides attending lectures and plenary sessions, participants had the opportunity to visit different institutions, such as the Agency for Science, Technology and Research (A*STAR).

The event was kindly sponsored by the National Research Foundation of Singapore; and besides speakers there were other distinguished people, such as the President of Singapore with whom participants could have a chat (see photo below).

The event was well publicised in various media outlets.

All in all, a very cool event, from the opening to the closing ceremony. So if you are someone who is considering to apply for GYSS 2017 (or later), and you found this blog post by searching for more information on GYSS, my recommendation is do not hesitate: it’s worth a long travel 🙂

Here are some photos from the event, the campus of the university, and some landmarks of Singapore. My favourite one is with Dr Leslie Lamport, the recipient of the Turing Award, and the creator of LaTeX!

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and one with Dr Leslie Lamport…

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UDMV 2015 held at TU Delft

After months of preparations, the Eurographics Workshop on Urban Data Modelling and Visualisation 2015 has finally been held on Monday 23 November. Previous editions of the workshop have been collocated with the Eurographics conference series, so we are happy that the first independent edition of the workshop has been hosted by us at TU Delft.

The workshop included the presentations of 11 peer-reviewed papers and 2 technical talks. Most authors and participants travelled from abroad, which shows that there is a substantial interest in this topic and that UDMV has a solid prospect of continuing as an independent event.

The papers were interesting, and the audience was mixed: from GIS to computer graphics, which warranted interesting discussions about common challenges and future collaborations. That was exactly the aim of the event.

Now back to writing papers 🙂



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Analysis of the new (2015) Impact Factors of GIS journals

[Update: for the impact factors released in June 2016 read the new blog post]

Thomson Reuters has recently released the 2015 edition of the Journal Citation Reports, a publication that contains the impact factors of journals they index.

I have compared the new impact factors to the previous ones (from the 2014 edition of JCR) for several GIS journals indexed in Web of Science. The result is shown below. Both the relative and absolute IF change are included.

Old vs. new impact factors for several GIS journals

Old vs. new impact factors for several GIS journals

It’s interesting to see that almost all GIS journals have seen the increase of their impact factor, some of them considerably: Cartography and Geographic Information Science has almost doubled it!

ISPRS International Journal of Geo-Information is the newest addition to Web of Science, but it is too recent to have an impact factor. According to the editors of the journal, the JCR that will be published in July 2016 will contain the IF for IJGI.

Please note that this is my personal list of indexed GIS journals, and it may differ from your preferences. For a more comprehensive list please see the internal list of my group.

Update: Martin Tomko has a related analysis about the temporal trends in Google Metrics of GIScience periodicals.

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Announcement of the UDMV Workshop 2015

I am happy to announce that my group is hosting this year’s edition of the Eurographics Workshop on Urban Data Modelling and Visualisation. It will be held on 23 November 2015 at TU Delft. The event is intended to bridge and explore the synergies between the computer graphics and GIS fields.

Previous editions have been organised in Spain in 2013 and in France in 2014 as a co-located event of the Eurographics conference.

Please find the call for papers and more information on the event’s website.


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A list of free/open CityGML data

Some time ago I’ve started to compile a list of CityGML open data initiatives. There are not many freely available 3D city models stored in CityGML, so it’d be a good idea to maintain an inventory. The list can be found at the CityGML wiki.

If you are aware of a dataset not listed, please let me know.


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Timelapse of writing a GIS research paper

I’ve written a few scripts to generate the timelapse of the writing of my recent 3D Geoinfo 2014 paper. This timelapse has been been inspired by similar work.

The timelapse comprises 520 versions of the paper in 10 fps, from the first day of work until the camera-ready copy, including one round of reviews.

Each time LaTeX/BibTeX was run the scripts generated a timestamped copy of the manuscript. Later each page was converted to PNG, the PNGs were stitched into a grid (one PNG per version), and a video was assembled (one version = one frame). More information about the workflow can be found on Vimeo.

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Hello 3D world

Welcome to my blog. It will cover mostly 3D GIS, my PhD, and other related stuff.

The name “Levelling the detail” was influenced by the topic of my PhD: level of detail (LOD), which is a principal topic in 3D GIS, and my most used term during my four-year endeavour at TU Delft.

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