Jun 142013
 

Slides (in German) for my recent talk about our geolocation and voting project at the Bamberg Graduate School of Social Sciences. The presentation is based on

  • Arzheimer, Kai and Jocelyn Evans. “Geolocation and voting: candidate-voter distance effects on party choice in the 2010 General Election in England.” Political Geography (2012). doi:10.1016/j.polgeo.2012.04.006
    [BibTeX] [Abstract] [Download PDF] [DATA]
    The effect of geographical distance between candidate and voter on vote likelihood in the UK is essentially untested. In systems where constituency representatives vie for local inhabitants’ support in elections, candidates living closer to a voter would be expected to have a greater probability of receiving that individual’s support, other things being equal. In this paper, we present a first test of this concept using constituency data (specifically, notice of poll address data) from the British General Election of 2010 and the British Election Survey, together with geographical data from Ordnance Survey and Royal Mail, to test the hypothesis that candidate distance matters in voters’ choice of candidate. Using a conditional logit model, we find that the distance between voter and candidates from the three main parties (Conservative, Labour and Liberal Democrat) matters in English constituencies, even when controlling for strong predictors of vote-choice, such as party feeling and incumbency advantage.

    @Article{arzheimer-evans-2012,
      author = {Arzheimer, Kai and Evans, Jocelyn},
      title = {Geolocation and voting: candidate-voter distance effects on party choice in the 2010 General Election in England},
      abstract     = {The effect of geographical distance between candidate and voter on vote likelihood in the UK is essentially untested. In systems where constituency representatives vie for local inhabitants' support in elections, candidates living closer to a voter would be expected to have a greater probability of receiving that individual's support, other things being equal. In this paper, we present a first test of this concept using constituency data (specifically, notice of poll address data) from the British General Election of 2010 and the British Election Survey, together with geographical data from Ordnance Survey and Royal Mail, to test the hypothesis that candidate distance matters in voters' choice of candidate. Using a conditional logit model, we find that the distance between voter and candidates from the three main parties (Conservative, Labour and Liberal Democrat) matters in English constituencies, even when controlling for strong predictors of vote-choice, such as party feeling and incumbency advantage.},
      journal = {Political Geography},
      year = 2012,
      doi = {10.1016/j.polgeo.2012.04.006},
      pages        = {301--310}
      html          = {http://www.kai-arzheimer.com/paper/geolocation-voting-candidate-voter-distance-effects-party-choice-2010-general-election-england},
      data          = {http://hdl.handle.net/1902.1/17940},
      url          = {http://kai-arzheimer.com/arzheimer-evans-geolocation-vote-england.pdf}
    }

.
The full PDF for the presentation is here.

Jun 112013
 

Extreme Right buffs rejoice, right-wing populist anoraks exult: The summer (?) 2013 edition of the Extreme Right Bibliography is out. Since its last instalment, I have added 19 new titles (mostly journal articles), bringing the total count up to 437. As always, please do remember that this is one man’s obsession. If you think that there is something missing, please drop me a line.

Jun 012013
 

What is the Delta Method?

I have used the delta method occasionally for years without really understanding what is going on under the hood. A recent encounter with an inquisitive reviewer has changed that. As it turned out, the delta method is even more useful than sliced bread, and much healthier.

The delta method, whose foundations were laid in the 1940s by Cramér (Oehlert 1942), approximates the expectation (or higher moments) of some function  nlcom and the Delta Method of a random variable  nlcom and the Delta Method by relying on a (truncated) Taylor series expansion. More specifically, Agresti (2002: 578) shows that (under weak conditions) for some parameter  nlcom and the Delta Method that has an approximately normal sampling distribution with variance  nlcom and the Delta Method, the sampling distribution of  nlcom and the Delta Method is also approximately normal with variance  nlcom and the Delta Method, since  nlcom and the Delta Method is approximately linear in the neighbourhood of  nlcom and the Delta Method. The delta method can be generalised to the case of a multivariate normal random vector (Agresti 2002: 579) such as the joint sampling distribution of some set of parameter estimates.

In plain words, that means that one can use the delta method to calculate confidence intervals and perform hypothesis tests on just about every linear or nonlinear transformation of a vector of parameter estimates. If you are interested in the ratio of two coefficients and need a confidence interval, if, for some reason, you need to know if  nlcom and the Delta Method with some probability, the delta method is your friend.

The Delta Method and nlcom

Stata’s procedure nlcom is a particularly versatile and powerful implementation of the delta method. As a post-estimation command, nlcom accepts symbolic references to model parameters and computes sampling variances for their linear and non-linear combinations  and transformations. If you can write down the formula of the transformation, nlcom will spit out the result, standard error and confidence interval, and will even store the full variance-covariance matrix of the estimates. That, in turn, means that amongst other things, you can abuse Stata’s built in procedures to implement your own estimators.

What’s not to like? Well, for one thing, Stata gives no indication of how well the approximation works. It’s always worth checking that the results look reasonable, and in particularly complex circumstances, one should use simulation/bootstrapping for double checking. But bascially,>nlcom is great fun.

References

Agresti, Alan. 2002. Categorical Data Analysis. 2 ed. Hoboken: John Wiley.

Oehlert, Gary W. 1992. “A Note on the Delta Method.” The American Statistician
46(1):27–29.

May 242013
 

The “Blue Books” have been around for more than 30 years. For each Bundestag election, there is a massive edited volume that deals with each and every aspect of this particular event.And for more than three decades, editors have urged authors and publishers to get on with their respective jobs. Inevitably, the massive tomes have always come out just in time for the next election.

In line with this great tradition, VS/Springer has published the most recent addition to the collection in early May. Our chapter looks (once more) into the differences between voters in the former Federal Republic and their eastern compatriots in the 2009 election. While these differences persist, we find that people in the West are also deviating from traditional patterns of voting behaviour. (In German)

bundestagswahl 05 stimmzett New Publication: The Left, East vs West, and the 2009 Election
Foter.com / Public domain
May 192013
 

These are the slides for my Oxford talk on competition between the Centre Left and the Extreme Right (aka Working Class Parties 2.0) for the working class vote in Western Europe. The presentation is based on

  • Arzheimer, Kai. “Working Class Parties 2.0? Competition between Centre Left and Extreme Right Parties.” Sociology of the Extreme Right. Ed. Rydren, Jens. London, New York: Routledge, 2012. 75-90.
    [BibTeX] [Abstract] [Download PDF] [HTML]
    The propensity of workers to vote for the Extreme Right has risen significantly. This “proletarisation”" is the result of the interplay between a long-term dealignment process and increasing worries amongst the European working classes about the immigration of cheap labour. As a result, Western European Centre Left parties may find themselves squeezed between the New Right on the one hand and the New Left on the other. There is no obvious strategy for dealing with this dilemma. Staying put will not win working class defectors back. Toughening up immigration policies is unpalatable for many party members, does not seem to make Social Democrats more attractive for working class voters, and might eventually alienate other social groups.

    @InCollection{arzheimer-2012c,
      author = {Arzheimer, Kai},
      title = {Working Class Parties 2.0? Competition between Centre Left and Extreme Right Parties},
      booktitle = {Sociology of the Extreme Right},
      publisher = {Routledge},
      year = 2012,
      pages        = {75--90},
      editor = {Rydren, Jens},
      abstract = {The propensity of workers to vote for the Extreme Right has risen significantly. This "proletarisation"" is the result of the interplay between a long-term dealignment process and increasing worries amongst the European working classes about the immigration of cheap labour. As a result, Western European Centre Left parties may find themselves squeezed between the New Right on the one hand and the New Left on the other. There is no obvious strategy for dealing with this dilemma. Staying put will not win working class defectors back. Toughening up immigration policies is unpalatable for many party members, does not seem to make Social Democrats more attractive for working class voters, and might eventually alienate other social groups.},
      url          = {http://www.kai-arzheimer.com/working-class-parties-extreme-right.pdf},
      html          = {http://www.kai-arzheimer.com/extreme-right-working-class-centre-left-competition/},
      address = {London, New York}
    }

The full PDF for the presentation is here.

May 142013
 

Every remotely relevant reference I came across during the last 15 years or so resides in a single bibtex file. That is not a problem. The problem is that I’m moving into a shiny, new but somewhat smaller office, together with hundreds of copies of journal articles and hundreds of PDFs. Wouldn’t it be good to know which physical copies are effectively redundant (unreadable comments in the margins aside) and can therefore stay behind?

The trouble is that bibtex files have a rather flexible, human readable format. Each entry begins with the @ sign, followed by a type (book, article etc.), a reference name,  lots of key/value pairs (fields) in arbitrary order,  and even more curly braces.

grep @ full.bib|wc -l tells me that I have 2914 references in total. grep binder|wc -l (binder is a custom field that I use to keep track of the location of my copies) shows that I have printed out/copied 712 texts over the years, and grep file|wc -l indicates that there are 504 PDFs residing on my filesystem. But what is the magnitude of the intersection?

My first inclination was to look for a suitable Python parser/library. Pybtex looked good in principle but is underdocumented and had trouble reading full.bib, because that is encoded in Latin 1. So it was endless hours of amateurish coding and procrastination ahead. Then I remembered the “do one thing, and do it really well” mantra of old. Enter bibtool, which is a fast and reasonably stable bibtex file filter and pretty printer. Bibtool reads “resource files”, which are really just short scripts containing filtering/formatting directives. select = {binder ".+"} keeps those references whose “binder” field contains at least one character (.+ is a regular expression that matches any non-empty string). select = {file ".+"} selects all references for which I have a PDF. But bibtool applies a logical OR to these conditions while I’m interested in finding those references that meet both criteria.

The quick solution is to store each statement in a file of its own and apply bibtool twice, using a pipeline for extra efficiency: bibtool -r find-binder.rsc full.bib|bibtool -r find-pdf >intersection.bib does the trick and solves my problem in under a minute, without any coding.

As it turns out, there were just 65 references in both groups. Apparently, I stopped printing (or at least filing away) some time ago. Eventually, I binned two copies, but it is the principle that matters.

May 092013
 

Germany’s (very polite) answer to UKIP is “Alternative für Deutschland” (AfD), a new party that wants to abolish the Euro. While this is certainly a novelty in German party politics, I don’t think it’s a game changer for the September election. Why? Read my guest post on the AfD over at the LSE’s excellent European Politics and Policy blog.

Apr 282013
 
Diliff / Foter.com / CC BY-SA

Thanks to colleague Kyriaki Nanou and the generosity of the Anglo-German Programme, I’m taking my paper on the election between the Centre Left and the Extreme Right for the working class vote to Academic Wonderland (TM). Needless to say that I’m looking forward to this in the extreme (pun intended, but I largely failed?). Click here to read the full paper on “Working Class Parties 2.0? Competition between the Centre Left and the Extreme Right in Western Europe“.

radcliffe camera oxford oct 2006 Workers, the Centre Left and the Extreme Right
Academic DisneyDiliff / Foter.com / CC BY-SA
Apr 262013
 

Today is clearly a day for statistical songs (are there any other days?), so here are some links to get you started.

To kick of the stat song roundup, here are some … interesting insights into the culture that is biostatics, complete with some remarkably dreadful audio material.

Obviously, you tube has a whole channel devoted to statistical songs, featuring, inter alia, Michael Greenacre, of Correspondence Analysis fame. To the true connoisseur,  it might appear a bit overproduced, but this little gem on Single Value Decomposition is very neat.

For the Structural Equation Modelling buffs, nothing compares to Alan Reifman’s annual reprise of  “SEM – the Musical”.

But for the purists, there is only one thing, something that I have watched with awe (and slowly building shock) growing beyond all expectations. The conspiracy against Frequentism have their very own book of Bayesian praise, complete with  LaTex  source, now compromising 40-odd songs including some “previously lost classic songs”, including “Bayesians in the night” (two versions, actually).