The Wikidata scholarly profile page

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Recently Lambert Heller wrote an overview piece on websites for scholarly profile pages: “What will the scholarly profile page of the future look like? Provision of metadata is enabling experimentation“. There he tabularized the features of the various online sites having scholarly profile pages. These sites include (with links to my entries): ORCID, ResearchGate, Mendeley, Pure and VIVO (don’t know these two), Google Scholar and Impactstory. One site missing from the equation is Wikidata. It can produce scholarly profile pages too. The default Wikidata editing interface may not present the data in a nice way – Magnus Manske’s Reasonator – better, but very much of the functionality is there to make a scholarly profile page.

In terms of the features listed by Heller, I will here list the possible utilization of Wikidata:

  1. Portrait picture: The P18 property can record Wikimedia Commons image related to a researcher. For instance, you can see a nice photo of neuroimaging professor Russ Poldrack.
  2. Researchers alternative names: This is possible with the alias functionality in Wikidata. Poldrack is presently recorded with the canonical label “Russell A. Poldrack” and the alternative names “Russell A Poldrack”, “R. A. Poldrack”, “Russ Poldrack” and “R A Poldrack”. It is straightforward to add more variations
  3. IDs/profiles in other systems: There are absolutely loads of these links in Wikidata. To name a few deep linking posibilities: Twitter, Google Scholar, VIAF, ISNI, ORCID, ResearchGate, GitHub and Scopus. Wikidata is very strong in interlinking databases.
  4. Papers and similar: Papers are presented as items in Wikidata and these items can link to the author via P50. The reverse link is possible with a SPARQL query. Futhermore, on the researcher’s items it is possible to list main works with the appropriate property. Full texts can be linked with the P953 property. PDF of papers with an appropriate compatible license can be uploaded to Wikimedia Commons and/or included in Wikisource.
  5. Uncommon research product: I am not sure what this is, but the developer of software services is recorded in Wikidata. For instance, for the neuroinformatics database OpenfMRI it is specified that Poldrack is the creator. Backlinks are possible with SPARQL queries.
  6. Grants, third party funding. Well there is a sponsor property but how it should be utilized for researchers is not clear. With the property, you can specify that paper or research project were funded by an entity. For the paper The Center for Integrated Molecular Brain Imaging (Cimbi) database you can see that it is funded by the Lundbeck Foundation and Rigshospitalet.
  7. Current institution: Yes. Employer and affiliation property is there for you. You can see an example of an incomplete list of people affiliated with research sections at my department, DTU Compute, here, – automagically generated by the Magnus Manske’s Listeria tool.
  8. Former employers, education etc.: Yes. There is a property for employer and for affiliation and for education. With qualifiers you can specify the dates of employment.
  9. Self assigned keywords: Well, as a Wikidata contributor you can create new items and you can use these items for specifying field of work of to label you paper with main theme.
  10. Concept from controlled vocabulary: Whether Wikidata is a controlled vocabulary is up for discussion. Wikidata items can be linked to controlled vocabularies, e.g., Dewey’s, so there you can get some controlness. For instance, the concept “engineer” in Wikidata is linked the BNCF, NDL, GND, ROME, LCNAF, BNF and FAST.
  11. Social graph of followers/friends: No, that is really not possible on Wikidata.
  12. Social graph of coauthors: Yes, that is possible. With Jonas Kress’ work on D3 enabling graph rendering you got on-the-fly graph rendering in the Wikidata Query Service. You can see my coauthor graph here (it is wobbly at the moment, there is some D3 parameter that need a tweak).
  13. Citation/attention metadata from platform itself: No, I don’t think so. You can get page view data from somewhere on the Wikimedia sites. You can also count the number of citations on-the-fly, – to an author, to a paper, etc.
  14. Citation/attention metadata from other sources: No, not really.
  15. Comprehensive search to match/include own papers: Well, perhaps not. Or perhaps. Magnus Manske’s sourcemd and quickstatement tools allow you to copy-paste a PMID or DOI in a form field press two buttons to grap bibliographic information from PubMed and a DOI source. One-click full paper upload is not well-supported, – to my knowledge. Perhaps Daniel Mietchen knows something about this.
  16. Forums, Q&A, etc.: Well, yes and no. You can use the discussion pages on Wikidata, but these pages are perhaps mostly for discussion of editing, rather than the content of the described item. Perhaps Wikiversity could be used.
  17. Deposit own papers: You can upload appropriately licensed papers to Wikimedia Commons or perhaps Wikisource. Then you can link them from Wikidata.
  18. Research administration tools: No.
  19. Reuse of data from outside the service: You better believe! Although Wikidata is there to be used, a mass download from the Wikidata Query Service can run into timeout problems. To navigate the structure of individual Wikidata item, you need programming skills, – at least for the moment. If you are really desperate you can download the Wikidata dump and Blazegraph and try to setup your own SPARQL server.


So what can we use Wikicite for?

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Wikicite is a term for the combination of bibliographic information and Wikidata. While Wikipedia often records books of some notability it rarely records bibliographic information of less notability, i.e., individual scientific articles and books where there little third-party information (reviews, literary analyses, etc.) exists. This is not the case with Wikidata. Wikidata is now beginning to record lots of bibliographic information for “lesser works”. What can we use this treasure trove for? Here are a few of my ideas:

  1. Wikidata may be used as a substitute for a reference manager. I record my own bibliographic information in a big BIBTeX file and use the bibtex program together with latex when I generate a scientific document with references. It might very well be that the job of the BIBTeX file with bibliographic information may be taken over by Wikidata. So far we have, to my knowledge, no proper program for extracting the data in Wikidata and formatting it for inclusion in a document. I have begun a “wibtex” program for this, and only reached 44 lines so far, and it remains to be seen whether this is a viable avenue, whether the structure of Wikidata is good and convenient enough to record data for formatting references or that Wikidata is too flexible or too restricted for this kind of application.
  2. Wikidata may be used for “list of publications” of individual researchers, institutions, research groups and sponsor. Nowadays, I keep a list of publication on a webpage, in a latex document and on Google Scholar. My university has a separate list and sometimes when I write an research application I need to format the data for inclusion in a Microsoft Word document. A flexible program on top of Wikidata could make dynamic lists of publications
  3. Wikidata may be used to count citations. During the Wikicite 2016 Berlin meeting I suggested the P2860 property and Tobias quickly created it. The P2860 allows us to describe citations between items in Wikidata. Though we managed to use the property a bit for scientific articles during the meeting, it has really been James Hare that has been running with the ball. Based on public citation data he has added hundreds of thousands of citations. At the moment this is of course only a very small part of the total number of citations. There are probably tens of millions of scientific papers with each having tens, if not hundreds of citations, of citations, so with the 499,750 citations that James Hare reported on 11 September 2016, we are still far from covering the field: James Hare tweeted that Web of Science claims to have over 1 milliard (billion) citations. The citation counts may be compared to a whole range of context data in Wikidata: author, affiliated institution, journal, year of publication, gender of author and sponsor (funding agency), so we can get, e.g., most cited Dane (or one affiliated with a Danish institution), most cited woman with an image, etc.
  4. Wikidata may be used as a hub for information sources. Individual scientific articles may point to further ressources, such as raw or result data. I myself have, for instance, added links to the neuroinformatics databases OpenfMRI, NeuroVault and Neurosynth, where Wikidata records all papers recorded in OpenfMRI, as far as I can determine. Wikidata is then able to list, say, all OpenfMRI papers or all OpenfMRI authors with Magnus Manske’s Listeria tool.
  5. Wikicite information in Wikidata may be used to support claims in Wikidata itself. As Dario Taraborelli points out this would allow queries like “all statements citing journal articles by physicists at Oxford University in the 1970s”.
  6. Wikidata may be used for other scientometrics analyses than counting, e.g, generation of coauthor graphs and cocitation graphs giving context to an author or paper. The bubble chart above shows statistics for journals of papers in OpenfMRI generated with the standard Wikidata Query Service bubble chart visualization tool.
  7. Wikidata could be used for citations in Wikipedia. This may very well be problematic, as a large Wikipedia article could have hundreds of references and each reference needs to be fetched from Wikidata generating lots of traffic. I tried a single citation on the “OpenfMRI” article (it has later been changed). Some form of inclusion of Wikidata identifier in Wikipedia references could further Wikipedia bibliometrics, e.g., determine the most cited author across all Wikipedias.

Backup of directory

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I at times does not recall the command to backup a directory. So here for my own sake of reference:

$ rsync -au /home/fnielsen/Pictures/ /media/fnielsen/a4f11e07-3f63-45cc-bcab-e7d135c14b9c/backup/Billeder/

the -a is the standard archive option. the -u is ‘update’ (“skip files that are newer on the receiver”).

Page rank of scientific papers with citation in Wikidata – so far

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A citation property has just be created a few hours ago, – and as of writing still not been deleted. It means we can describe citation network, e.g., among scientific papers.

So far we have added a few citations, – mostly from papers about Zika. And now we can plot the citation network or compute the network measures such as page rank.

Below is a Python program using everything with Sparql, Pandas and NetworkX:

statement = """
select ?source ?sourceLabel ?target ?targetLabel where {
  ?source wdt:P2860 ?target .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .

service = sparql.Service('')
response = service.query(statement)
df = DataFrame(response.fetchall(),

df.sourceLabel = df.sourceLabel.astype(unicode)
df.targetLabel = df.targetLabel.astype(unicode)

g = nx.DiGraph()
g.add_edges_from(((row.sourceLabel, row.targetLabel)
    for n, row in df.iterrows()))

pr = nx.pagerank(g)
sorted_pageranks = sorted((rank, title)
    for title, rank in pr.items())[::-1]

for rank, title in sorted_pageranks[:10]:
    print("{:.4} {}".format(rank, title[:40]))

The result:

0.02647 Genetic and serologic properties of Zika
0.02479 READemption-a tool for the computational
0.02479 Intrauterine West Nile virus: ocular and
0.02479 Internet encyclopaedias go head to head
0.02479 A juvenile early hominin skeleton from D
0.01798 Quantitative real-time PCR detection of 
0.01755 Zika virus. I. Isolations and serologica
0.01755 Genetic characterization of Zika virus s
0.0175 Potential sexual transmission of Zika vi
0.01745 Zika virus in Gabon (Central Africa)--20

Occupations of persons from Panama Papers

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Can we get an overview of the occupations of the persons associated with the Panama Papers? Well … that might be difficult, but we can get a biased plot by using the listing in Wikidata, where persons associated with the Panama Papers seems to be tagged and where their occupation(s) is listed. It produces the plot below.


It is fairly straightforward to construct such a bubble chart given the new plotting capabilities in the Wikidata Query Service. Dutch Wikipedian Gerard Meijssen seems to have been the one who has entered the information in Wikidata linking Panama Papers to persons via the ‘significant event‘ property. How complete he yet has managed to do this I do not know. Our Danish Wikipedian Ole Palnatoke Andersen set up a page on the Danish Wikipedia at Diskussion:Panama-papirerne/Wikidata tabulating with the nice Listeria tool of Magnus Manske. Modifying Ole’s SPARQL query we can get the count of occupations for the persons associated with the Panama Papers in Wikidata.

SELECT ?occupationLabel(count(distinct ?person) as ?count) WHERE {
  ?person wdt:P793 wd:Q23702848 ; wdt:P106 ?occupation .   
  service wikibase:label { bd:serviceParam wikibase:language "en" . }
} group by ?occupationLabel

Some people may see that politicians are the largest group, but that might simply be an artifact of the notability criterion of Wikidata: Only people who are somewhat notable or are linked to something notable are likely to be included in Wikidata, e.g., the common businessman/woman may not (yet?) be represented in Wikidata.

The bubble chart cuts letters of the words for the occupation. ‘murd’ is murderer. Joaquín Guzmán has his occupation set to murderer in Wikidata, – without source…


Review and comment on Nick Bostrom’s book Superintelligence

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Back in the 1990s I spent considerable computer time training and optimizing artificial neural networks. It was hot then. Then around year 2000 artificial neural networks became unfashionable with Gaussian processes and support vector machines taking over. During the 2000s computers got faster and some engineers turned to see what graphics processing units (GPU) could do besides doing computer rendering for computer games. GPUs are fast for matrix computations which are central in artificial neural network computations. Oh and Jung’s 2004 paper “GPU implementation of neural networks” seems to be the first according to Jurgen Schmidhuber describing the use of GPUs for neural network computation, but it was perhaps first when Dan Ciresan from Politehnica University of Timisoara began using GPUs that interesting advances began: In Schmidhuber’s lab he trained a GPU-based deep neural network system for Traffic Sign Classification and managed to get superhuman performance in 2011.

Deep learning, i.e., computation with many-layered neural network systems, was already then taking off and now broadly applied where the training of a system for computer gaming (classic Atari 2600 games) is perhaps the most illustrative example on how flexible and powerful modern neural networks are. So in limited domains deep neural networks are presently taking large steps.

A question is whether this will continue and whether we will see artificial intelligence system having more general superhuman capabilities. Nick Bostrom‘s book ‘Superintelligence‘ presupposes so and then starts to discuss “what then”.

Bostrom’s book, written from the standpoint of an academic philosopher, can be regarded as a elaboration from the classic Vernor Venge “The coming technological singularity: how to survive in the post-human era” from 1993. It is generally thought that if or when artificial intelligence become near-human intelligent the artificial intelligence system will be able to improve itself and once improved it will be able to improve yet more, resulting in a quick escalation (Verge’s ‘singularity’) with the artificial intelligence system becoming much more intelligent than humans (Bostrom’s ‘superintelligence’). Bostrom lists surveys among expert showing that the median time for the human-level intelligence is estimated to be around year 2040 and 2050, – a share of experts even believe the singularity will appear in the 2020s.

The book lacks solid empirical work on the singularity. The changes around the industrial revolution is discussed a bit and the horse in society in the 20th Century is mentioned: From having widespread use for transport, its function for humans would be taken over with human-constructed machines and the horses sent the butcher. Horses in the developed world are now mostly being used for entertainment purposes. There are various examples in history where a more ‘advanced’ society competes with an established less developed: neanderthal/modern humans, the age of colonization. It is possible that a superintelligence/human encounter will be quite different though.

The book discusses a number of issues from a theoretical and philosophical point of view: ‘the control problem’, ‘singleton’, equality, strategies for uploading values to the superintelligent entity. It is unclear to me if a singleton is what we should aim at. In capitalism, a monopoly seems not necessarily to be good for society, and in market economy societies put up regulation against monopolies. Even with a superintelligent singleton it appears to me that the system can run into problems when it tries to handle incompatible subgoals, e.g., an ordinary desktop computer – as a singleton – may have individual processes that require a resource which is not available because another resource is using it.

Even if the singularity is avoided there are numerous problems facing us in the future: warbots as autonomous machines with killing capability, do-it-yourself kitchen-table bioterrorism, general intelligent programs and robots taking our jobs. Major problems with it-security occur nowadays with nasty ransomware. The development of intelligent technologies may foster further inequality where a winner-takes-all company will rip all benefits.

Bostrom’s take home message is that the superintelligence is a serious issue, that we do not know how to tackle, so please send more money to superintelligence researchers. It is worth alerting society about the issue. There is general awareness of the evolution of society for some long term issues such as the demographics, future retirement benefits, natural resource depletion and climate change issues. It seems that development in information technology might be much more profound and requires much more attention than, say, climate change. I found Bostrom’s book a bit academically verbose, but I think the book has quite important merit as a coherent work setting up the issue for the major task we have at hand.


(Review also published on LibraryThing).

Rejsekort – advantages and disadvantages

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Rejsekortet is made by a company whose parent company Thales has been involved in corruption to an extent that a Danish retirement fund has banned investment in it. It was a story that one of the Danish tabloids could bring to the frontpage.

The cost of the investment is estimated to be around 2 milliard kroner. According to some calculations the Rejsekort will be 3 times as expensive to administer as the old system. Other calculations have found that it only was twice as expensive.

If you forget to check out the cost has been 50 kroner. Children has a problem remembering to check out. A nerd has constructed a smartphone app to remind people to check out, so now you only need to check in, set the timing for the alarm in the app and then check out when the alarm sounds… Some time ago I got the Rejsekort and tried it on several trips. I forgot it so many times – perhaps around of the third of the time I used it – that I switched back to the klippekort. It cost me 50 kroner each time I forgot. 25 kroner is for the ordinary ticket. In July 2013 the klippekort kort was to be abandoned, so I started to use Rejsekortet again, thinking I just needed to get into the habit of remembering the check-out. I managed to remember to check-out several times by holding the Rejsekort in my hand during the travel. One day I forgot and got around a kilometer away from the station before I remembered that I forgot to do the check-out. Luckily a bus stop was close by and I got in a stopping bus, checked in, immediately checked out and got out of the bus. I believed this saved me 25 kroner. Unfortunately a few days later I forgot to check out again. I had traveled from Lyngby to Nørreport and then switched to the Metro for the DR Byen. In Lyngby I checked in and at Nørreport I checked out, because I had to check in two bikes on the Rejsekort (Bikes travel freely in the S-tog between Lyngby and Nørreport, but in the Metro you pay). Getting off at DR Byen I forgot to check out. I discovered that after cycling perhaps 3 kilometers away from the station. Thinking that it was only a question of a 30 kroner difference in penalty (a penalty fare) I cycled on. I later saw that Rejsekorte took first 20 kroner for the trip from Lyngby to Nørreport, then a further penalty. Why this is so I do not know. I have used Rejsekort-like system in Amsterdam where I forgot to check out in the trams. However, the Rejsekort I had there was a week-based version, so I presume it did not matter. I have used Oyster Card in London I have had no problems as you need to check out to get past the gate in the train stations. The same goes for Rejsekort-like system in Stockholm. There are no gates at the train station of Copenhagen or anywhere else in Denmark. The introduction of gate will be an expense and furthermore, because of the possibilty of fire evacuation, the stations would need to be manned. The problem with missing check-out and the travelers complaint let the Rejsekort to change the penalty from 50 kroner to 25 kroner. Lately, I have been setting up an alarm on my phone, but even with that I apparently managed to forget to check out (I could almost have sworn that I checked out, but Rejsekortet sent me an email about a missing check-out).

There exists special Rejsekort for young people, Rejsekort Ung. This can give you a discount. You need have a discount card (apparently another card) if you want the discount. At one point young people needed to bring the discount card along when they were not entitled to the discount. This oddity was removed.

For a travel I had used the klippekort (where you do not need to check out) and then after a while got this unpleasant obsessive compulsive thought that I forgot to check out… I went to a party were a guy remembered that he had forgot to check out, so he left the party to walk back to the train station to check out. Away half an hour.

The check-in and check-out terminals resemble each other. A YouTube video shows a user fails to check out, – instead he is checking in again. The problem has led the company to put stickers on the stands with a more clear indication. Interestingly, blogger Georg Strøm found a case where the sticker said the terminal was a check-out type, while it actually was a check-in type.

The Rejsekort for a large part requires the use of the Internet. This may be difficult for the elderly.

Rejsekort does not (yet!?) work well for institutions/organization. For example it does not work well for a kindergarten since the institution cannot have a Rejsekort. However, an employee can use his/her own personal Rejsekort to pay for the travel of the children and then get reimbursed.

It is difficult to know the price of your travel. Rejsekort A/S suggests using their online calculator. The media reports amazing stories about strange unpredictable pricing. Denmark has a strong tradition for enforcing stores to show the final price. The obvious contrast to the opaque pricing of Rejsekort travels have been noted.

The number of check-in and -out for travellers increases. Say, you travel from Lyngby to Frederiksberg with one change of means of transportation. With a “Pendlerkort” you never need to check in or out. With the Rejsekort you need to scan 3 times: check in, check in again for the second leg and check out. If you forget one of them you may face a 750 kroner penalty, a penalty on unknown number of kroner (120? kroner) or 25 kroner penalty, respectively.

A user has reported that money added to the Rejsekort account is not added to the card. That story sounds too strange for me to be true but might be. Perhaps it is due to delays?

The same user also reports that the machine of the ticket checker cannot detect the check-in for the second leg travel.

He furthermore reports that terminals in busses were check-in terminals when people thought it was check-out.

If a terminal does not work when you get off you are in trouble. Apparently the Rejsekort support recommends waiting on the next bus to do the check-out. But in the countryside there may easily be many hours to the next bus.

I have experienced that the machine at the station for putting money on the Rejsekort was using several minutes for its transaction as it tried to communicate with the central payment system. Luckily, I was not in a hurry.

The Rejsekort system has failed nationwide. This happen in February 2014 for some hours.

The Rejsekort terminals in the busses are offline for most of the time. The information about check-in and -out are only synchronized when the bus gets back to its garage after work. Also terminals on the train stations are reported not to be in sync, but only updated every 4 hours (is this really correct?). Reportedly, the offline issue means that you can get a temporary penalty ticket for not checking out: If you take the train and check in, afterwards change to the bus and check in and check out, then your bus check in and out will not appear on the Rejsekort website and a temporary penalty will appear for up to 1 to 2 days.

The offline issue also means that you can add money to the account on the Rejsekort website, but the card and terminals do not know about it. If there is too small amount on the card, you cannot check in. Rejsekort suggests to always put money on the website well ahead of the travel or to use the automatic refill facility.

On the other hand you cannot put money on the card too early via the Rejsekort website. After a week the payment is cancelled!

Christian Dalager retweeted a one funny story. First in Danish: “Det. Stopper. Aldrig. RT @steffentchr Har fået et brev fra #Rejsekort om at de ikke havde min adresse. Altså et brev med posten.” In English: A guy received a snail mail letter from Rejsekort stating that they did not know his address. :-)

A rejsekort user has reported that the Rejsekort terminal may inadvertedly scan your Rejsekort, so that you get checked out and may face a penalty on 750 kroner. The scanners are apparently so sensitive that they can scan a card lying in a bag. The company Rejsekortet A/S states on one hand that people should keep bags away from scanners, on the other hand that it is impossible to be scanned without knowing it. A YouTube video shows an example of check-out with a wallet in a pair of trousers. My card on the other hand has been (while it worked) so insensitive that I had to take it out of my wallet. If I remember correctly foreign card–perhaps Oyster–could scan card in the wallet. And the position of the check in and out terminals on the train stations were such that inadvented check out would be excessively rare.

You have no means of prove to the ticket checker that you have made a check-in. My Rejsekort (apparently!?) malfunctioned while I was travelling having checked in. I got a ticket on 750 kroner. I got the issue resolved with Rejsekort and DSB.

If you are forgetful (as I am) and forget to check out too many times then your card may be blocked! It is reported that 300 people are blocked. In a news paper comment notable neuroscientist Albert Gjedde reports on his experience with getting his Rejsekort blocked without notice and himself a 1-year ban after just three forgetful checkouts.

The number of missing checkouts have been reported to be 2%. If a pendler (Danish for ‘commuter’) forgets to checkout in 2% of his/her travels, the number is actually a very large number: Consider the pendler travelling 400 times a year. On average he would have 8 missing checkouts per year. Given that your card may be blocked after 3 missing checkouts, then the average pendler is almost bound to get his card blocked, – and indeed this is what has been reported to have happened for a user. The mathematically inclined may attempt to solve an exercise in probability to get a feel for the 2%-problem. Hint: Negative binomial distribution. The conclusion seems to be that the Rejsekort hits a probabilistic wall, which is a very deep problem and where I can see no immediate solution.

Phone support is not good. Trying to find out what I should do with my card that was malfunctioning (or at least could not communitation with the terminal) I called the Rejsekort (all other options was gone: card at terminal didn’t work, no personnel on the station, “Rejsekortautomat” I could have tested would not have worked). I was on hold for around 13 minutes. At the end my call was interrupted. The cause of the interruption was unclear for me, perhaps low battery, bad coverage, my mishandling of the buttons on the phone or was it Rejsekortet that interrupted by call? If you cannot check out Rejsekort A/S suggest calling them and tell about the situation. The second time I called it was much faster. There was only one customer ahead of me in the queue. But it is probably optimistic to think that Rejsekort phone support may be able to solve your problem if you are in a hurry. The phone support and its waiting time is a common complaint on Trustpilot.

There have been problems with the homepage where you can check your travels. Given that you do not get a paper ticket with the price information it is problematic.

One Rejsekort strangeness is shown in a YouTube video: You can take children, dogs and bikes along on the Rejsekort, but only two types of them.

A customer reported experiencing that a check-in was not registered so he received a penalty.

Poul-Henning Kamp reported strange (wrong?) price computation in the Rejsekort system. One story involves travelling with 1’100 km/h with the train. Here the human ticket checker had his/her machine set to the wrong area. One must imaging that this has affected all the passengers in the train, that the ticket checker scanned. Rejsekort admits that this can happen, but claims that it happens extremely seldom. In these cases there seems to be no back-end data mining that can capture, warn and correct the issue. Instead the user has to check his/her travel and contact the Rejsekort support to get it corrected. It is unclear if Rejsekort expects the user to do this every time s/he uses the Rejsekort with a moving terminal.

One funny Rejsekort concept discovered by Søren Hugger Møller is null travels. Søren’s case is shortly described but too complex for me to understand, but essentially boils down to that you should pay 12 kroner if it happens again.

The password length on Rejsekort website can only be up to 15 characters.

You cannot see on the Rejsekort when you did the check-in. How long you are allowed to travel (“maksimumtiden”) apparently varies between zones. With the old Klippekort you could see the timestamp and read on the backside of the Klippekort how many hours and minutes you were allowed to travel. If you travel more than the “maksimumtiden” then your ticket is no longer valid and you can face a penalty.

When changing busses or trains it is not immediately clear whether you need to check in or check out. The automated speaker in the S-train clearly states that you should check in (again) and not check out. If you check out and check in (again) there is not a penalty or extra price AFAIU. A checkout may actually benefit you, because if a bus does not arrive (or its Rejsekort terminal does not work or it is delayed), you take a taxi or choose to walk and you did not check out, then you will face the extra 25 kroner bill. On the other hand if you do not check in (even though you have not checked out) then you may face a penalty. Rejsekort itself states if in doubt, check out.

Trustpilot user Camilla Engelshardt Kirkegaard has reported that during a travel with the same train she needs to get out of the train and check in and get back into the train.

Rejsekort stores your travel data. For those interested in privacy, such as MSS, NSA, FSB, BND, GCHQ, Frenchelon and non-governmental problematic organizations from a Danish point og view Rejsekortet may prove a valuable source of information to monitor a great part of Danes. The Rejsekort is constructed by a company associated with the French Thales. With the recent paranoia we got from Edward Snowden and Hans Jørgen Bonnichsen’s claim that the French are among the top most monitoring intelligence services one may wonder to which extent Frenchelon has access to Rejsekortet.

My card malfunctioned. On their FAQ they do not tell what to do. I called Rejsekortet to ask and they told that one should go to a station to have it checked, it was apparently not enough that I stated that I could not check in and the ticket checker could neither get a signal from the card. I then asked whether I could go to my local train station, but no no. Only at certain train stations with special Rejsekort ticket office is it possible to have the Rejsekort checked. I did go to such a Rejsekort ticket office, but it turned out that it was closed. Later I went to a Rejsekort ticket office that was actually open. After only waiting 20 minutes in a queue I managed to get to a person that scanned my card and found it not working. She could not do anything, but told me to go home and block my old malfunctioning Rejsekort and order a new Rejsekort. I now got a new Rejsekort, and now have 214.00 kroner dangling on my old Rejsekort, which apparently have not been transfered…!?

With the Klippekort you can make a quick return trip on the same ticket (as long as you travel within the time limit). With Rejsekortet you need two tickets one for the out-going and one for the return travel.

Travelling long distance you often want to buy a fixed seat. The Rejsekort does not entail this function. You will need to buy a separate ticket for the fixed seat.

One of the nice thing about airplane tickets is that the airline company handles delays on multilegged travels. Given that the Rejsekort is country-wide one should think that a notion of a end-to-end ticket is possible, – and indeed a very good feature if you are travelling to remote parts of Denmark were there is long interval between busses. It is not at all evident that this is the case. Take a combined train and bus ride. If the train is delayed and it is not evident that the bus or train company should handle my delay and I might simply miss the bus ride.

If you get a new credit card and need to associate that with the Rejsekort, the procedure is terribly complicated, one blogger calling it The absurd theater of the Rejsekort.

With my first Rejsekort broken I got a new one, but I still have some money on the old card with and with little know how on how to transfer that money to the new Rejsekort…

A minor issue on the website: Under the menu item “overview” (“Oversigt”) the “My travels (“Mine rejser”) claims that I have not yet used by Rejsekort (“Du har endnu ikke taget dit rejsekort i brug.”). For both of my Rejsekort listed this is simple wrong.

Some kind of system errors might occur making automatic refilling of the Rejsekort not working.

The Rejsekort is not good for tourists. A blank anonymous Rejsekort costs 80 kroner. The Swedish Stockholm Rejsekort card fee is 20 SEK, so well under a fourth.

Although Danish public transportation is heavily subsidized and partially owned by the government the Minister of Transportation says that he cannot control the companies making decisions about the Rejsekort.

The Rejsekort system does not allow you to check in a Rejsekort if you got another NFC card in your purse. I have a card for the door at my work and I need to take our my Rejsekort out of my purse to check in. It is technologically possible handle multiple cards, but the company behind Rejsekort has simply decided not to implement that detail.

Rejsekortet does not work well with the Pendlercard (special card for commuters). If you travel outside zones covered by a pendlercard you need to check in in the middle of you travel, e.g., rushing out of the train to find a check-in terminal quickly and jump on the train again.

For more complaints see the 85 items list from Politiken.

See also Rejsekortets own list in the action plan for better customer
exerience with Rejsekort


There has been a number of satisfied customers with the Rejsekort. One is Jakob Rosenkrantz de Lasson.

You do not have to know anything about the number of zones of travel before you buy a ticket is mentioned as an advantage. With the old Klippekort you need to figure out in advance how many zones you would be travelling.

Rejsekort stores your travel data. For those interested in self quantification it may be a valuable source. However, I do not think that Rejsekortet provides the data in a convenient format. And if you think that Rejsekort provides an API, well think again. You will probably have to scrape the webpage: Good luck…

Certain travels may get cheaper. In Odense’s ring zone 10 has been especially advantageous for travellers as you pays for only one zone compared to 3 zones with the non-Rejsekort system (FynBus is apparently considering to change the zoning in Odense because it is too advantageous). However, many users report that this is not the case for them. 1, 2. E.g., with an old fashion ticket you can get a discount, that is not handled with Rejsekortet. Another way that tickets may get cheaper is that with Rejsekortet you pay for “bird flight” distance, while for Klippekortet you pay for train track distance. However, if your Rejsekort are checked underway you still pay the train track price. However, there has been reported about travels getting more expensive with the Rejsekort.

You can get 20% off by travelling off-peak with the Rejsekort. This may a help alleviate the pressure on public transportation. It is unclear why this offer could not be made to people with a klippekort, e.g., they could have offered me to only use a 3 zones ticket for the ordinary 4 zone travel during peak hours.

Rejsekortet may clean up the complex structure of ticket zones and special rules. However, I have no knowledge that this have actually occurred.

Rejsekortet can give a more precise overview of the travel pattern of users. This allows a more fair distribution of the income between the Metro, the bus companies and DSB running the S-trains. This is only of very indirect advantage for the user of the public transporation and actually puts an extra burden on the user as s/he needs to check in when changing from one type of transport to another. The use of camera has been suggested to count the passengers instead, avoiding to burden the user.

Rejsekort uses NXP-type NFC which certain smartphones can read. Independent developer Casper Bang has developed a smartphone app that allows the user to read the Rejsekort and see the travels and the amount of money on the card.

With automatic refill for the Rejsekort you do not need to buy ticket or put money on the card. This happens automatically. I have this opted in for this functionality. I means that Rejsekort can suck money out of my bank account. I hope no errors happens with the system, so that my bank account is emptied. It is unclear if there is any upper limit on the withdrawal from the bank account and if good intelligent monitoring is at hand so that suspicious use is flagged. There may be month between my checks on the self-service where all travels are listed and weeks between my use of the Rejsekort, so I fear that if my card is stolen the thief will be able to withdraw substantial amounts of money from my bank account.