Can Twitter predict the new Dutch trade union president

Number of tweets in which candidates are mentioned

According to an American study, you can predict the outcome of elections by simply counting how often the names of the candidates are mentioned on Twitter. Members of the Dutch union confederation FNV are currently voting for their new president (it has been claimed this is the first time in the world union members get to directly elect their confederation president). Would it be possible to predict who will be the new FNV president using Twitter?

Since last Friday, I’ve been collecting the tweets containing the term ‘FNV’; so far, there are over 2,500. In those tweets, the incumbent Ton Heerts is mentioned 204 times, whereas his challenger Corrie van Brenk is mentioned 146 times. In short, if Twitter is a good predictor (which of course is a matter for debate), the contest is tighter than one might have expected.

The graph above shows the results for the days for which complete data is available. On Saturday, Van Brenk got some attention because something she had said had been fact checked (and found to be correct). On Sunday, Heerts was mentioned because he appeared on a TV show hosted by Eva Jinek. On 1 May, it was officially announced who the candidates are and they had a debate.

Update - Updated to include 13 May, the final voting day. In sum, Van Brenk was mentioned 497 times and Heerts 631. It has since been announced that Heerts has won the election (of course, this doesn’t necessarily mean that the method is sound; in order to make such claims one would need to evaluate a fair amount of predictions).
Influences reflected in the graph include: Factcheck confirms Van Brenk statement (27 April); Heerts in Eva Jinek TV show (28 April); candidates officially announced (1 May); debate in Buitenhof TV show (5 May); problems at tax authorities that Van Brenk’s Abvakabo FNV had warned about (6 May); Van Brenk interview at (9 May); Van Brenk in radio show (10 May); Heerts at presentation of initiative to train technical staff (13 May); EenVandaag TV show poll predicts Heerts will win (13 May).
The graph may not be visible in older versions of Internet Explorer.


I collected tweets using the Twitter Streaming API (the ‘firehose’), in the way described here. I prepared the data using Python and analysed it using R (find the code on Github). The graph was created with D3.js.
I looked into how influential twitterers are (how many followers, how often listed) and into their backgrounds (e.g., do they mention ‘fnv’ in their profile). The most important finding is that twitterers who mention Van Brenk, more often mention ‘abva’ or ‘akf’ in their profile - not surprising since Van Brenk is currently president of Abvakabo FNV, the public sector union affiliated to the FNV.
The American study on Twitter as a predictor of election outcomes was done by DiGrazia c.s. and can be found here. Some remarks on their study:

  • Yes, twitterers are only a small part of the population and no, they’re not representative of the entire population. Likely, Twitter is dominated by a small, active incrowd. It’s also correct that tweets mentioning a candidate need not endorse them; they may as well be critical. Despite all this, DiGrazia c.s. found that mentions on Twitter consistently predict election outcomes. Perhaps they are an indicator of something else - e.g. media attention or how actively people are campaigning for a candidate.
  • Of course, this method doesn’t provide any certainty on who will win. It’s possible for a candidate to get almost 100% of the tweet share and still lose (at least, that’s what the scatterplots of DiGrazia c.s. suggest).
  • It’s unclear to what extent the conclusions of the American study can be generalised to other situations. It’s therefore a bit of a gamble to use this method to predict who will be the next president of the FNV.

Clint Eastwood won the LAUGHTER contest

I’m not sure what this says about the audiences at US national party conventions, but among a sample of 16 speeches, Clint Eastwood’s was the one that elicited the most laughter (Rand Paul’s got most applause). Among the presidential candidates, Obama won the applause contest, while being about equally funny as Romney.

For the second lesson of Alberto Cairo’s online data visualisation course, we were asked to comment on and perhaps redesign this convention word count tool created by the NYT. I wouldn’t be able to do such a cool interactive thing myself (I got stuck in the jQuery part of Codeyear), so I decided to focus on differences between individual speeches instead.

First I needed the transcripts – preferably from one single source to make sure the transcription had been done in a uniform way. As far as I could find, Fox News has the largest collection of transcripts online. As a result, Republican speakers are overrepresented in my sample, but that’s ok because the key Democratic speakers are included as well.

I wrote a script to do the word count (I’m sure this could be done in a more elegant way). One problem with my script was that html-code got included in the total word count. I thought I could correct this by subtracting 1,000 from each word count, but this didn’t work so well, so I had to make some corrections.

This assignment was a bit of a rush job so I hope I didn’t make any stupid mistakes.

Programmeren op de iPhone?

Computercode is de language du jour, las ik in de NYT. Iedereen wil leren programmeren en er zijn zelfs iPhone apps voor. Nou vind ik de iPhone handig voor heel veel dingen, maar ik vraag me ernstig af of programmeren (foutloos tekst intypen met veel leestekens) daar ook bij hoort. Dat neemt natuurlijk niet weg dat ik wel nieuwsgierig ben naar wat die apps dan kunnen.

Er blijken inderdaad allerlei apps te bestaan. Het meest intrigerend is deze waarmee je Pythonprogramma’s kan uitvoeren (althans, print "Hallo wereld" werkt). Er zitten ook oefeningen bij (denk ik) maar die zijn in het Chinees. Let ook op de decoratieve achtergrond.

Praktischer is deze app waarmee je quizvragen kan beantwoorden over wat stukjes Pythoncode doen. Leuk tijdverdrijf als je op de trein staat te wachten, heb je toch het gevoel dat je wat nuttigs doet. Maar ik denk dat ik me voorlopig nog maar even op JavaScript moet concentreren.


The NYT called computer code the language du jour, there are even iPhone apps to learn programming. I found one that looks cool but is half in Chinese, and a quizz to test your knowledge of Python. But I think I should focus on JavaScript for now.