Når den offentlige mening er meningsløs

Udover min nylige artikel i European Journal of Political Economy om valgparadokser i.f.m. USA-præsidentvalget i 2016 og min artikel i Oxford Handbook of Public Choice om social choice teori i.f.m. den socialdemokratiske velfærdsstat, har jeg fornylig berørt social choice teori i et debatindlæg om Brexit i Berlingske.  Her er et klip:

"Vi er vant til at tænke på demokrati som, at flertallet bestemmer. Vi kan faktisk slet ikke forestille os et demokrati, der er betegnelsen værdig, hvor det ikke er tilfældet.
Problemet er blot, at der ikke altid er en »folkevilje« et sted derude. For så snart mere end to mennesker skal vælge mellem mere end to alternativer, kan det være, at selve afstemningsformen bliver afgørende for udfaldet – eller at der slet ikke findes noget, som ikke er mindre foretrukket end noget andet.


Sådanne fænomener har matematikere studeret i 250 år. De kalder den slags et »cyklisk flertal«: Et flertal foretrækker A fremfor B. Et andet flertal vil have B fremfor C. Et tredje flertal foretrækker C fremfor A. Altså lidt ligesom sten slår saks, saks slår papir, og papir slår sten.

Hva’ ba’? Pointen kan illustreres med dette eksempel: Tre rygere sidder om et stort rundt bord og skal sammen dele et askebæger. Uanset hvor på bordet askebægeret stilles, vil der altid være et andet sted, som to af de tre vil foretrække mere end der, hvor askebægeret står. Altid. Selv hvis det står lige midt på bordet.

[... ]Den britiske Brexit-proces, der i disse uger synes næsten kaotisk, illustrerer problemet. Da briterne i 2016 stemte »leave« var det med et relativt beskedent flertal fremfor »remain«. Men hver af de to sider består reelt af flere undergrupper, herunder nogle der er utilfredse med EU, men som hverken ønsker, at Storbritannien skal kappe alle relationer til kontinentet, eller at tingene skal forblive, som de var. Men ved afstemningen måtte mange af disse så, fordi de kun fik to alternativer, vælge deres næstmest foretrukne.

Det kan man se antydninger af i mange meningsmålinger, der medtager både »hård Brexit«, »blød Brexit« og fortsat uændret EU-medlemskab: Her er der aldrig et absolut flertal (mere end 50 pct.) bag nogle af de tre muligheder. Enkelte meningsmålinger antyder også, at det kan være tæt på en »folkevilje«, hvor et flertal foretrækker en »hård Brexit« fremfor fortsat EU-medlemskab, og dette mere end Mays aftale, og denne fremfor »hård Brexit«. Eller hvor et flertal vil have Mays aftale frem for uændret medlemskab og dette frem for »hård Brexit«, men måske dette frem for Mays aftale. Kun få procent af stemmerne skal flyttes den ene eller anden vej for at give ganske forskellige resultater."

A couple of new papers out: Danish political system + social democracy/public choice

I have a couple of new papers coming out in anthologies.  One is with my good colleague, Karina Kosiara-Pedersen, "Change and stability in the Danish party system", in M. Lisi (ed.): Party system change, the European crisis and the state of democracy. London; N.Y.: Routledge, 2018, pp. 63-79 (Routledge Studies on Political Parties and Party Systems).


Here is from the introduction:

"When looking at the Danish political system in the first decade and a half of the new millennium, it is tempting to quote Lampedusa’s words from  Il Gattopardo: That everything must change so that everything can remain the same. New parties emerged, semi-old parties disappeared but, on the surface, most things seem largely the same. Yet that would to a large extent be to ignore some quite subtle but important changes, fi rst and foremost that the “quadropoly” of the “four old parties”, which has dominated Danish politics for a century, have declined in strength and given way to a much more fragmented and multipolar party system. This change has come about gradually. There is no particular revival after the economic or immigration crises and neither does the framing of new parties indicate a link. While these crises have had an impact on the political agenda and policies, they do not seem to have had an impact on the confi guration of the Danish party system.  The historic core of the Danish party system has declined. The four old parties won nine out of ten votes prior to the earthquake election of 1973 at which they gained only 58 percent. In the period under scrutiny here, the combined electoral base of these four parties has shrunk from three out of four in 2001 and 2005 to two-thirds in 2007 and 2011 and only just over half in 2015. While they still provide a core, they simply do not dominate the party system to the same extent as they used to. This decline in the support for the oldest parties is similar across the Scandinavian countries but more marked in Denmark."

The other is my "Public choice and social democracy" in R. Congleton, B. Grofman & S. Voigt (eds.) Oxford handbook of public choice. Oxford: Oxford University Press, 2019, Vol. 1. (Oxford Handbooks). Here is the abstract:

"Since World War I, “social democracy” has been one of the most influential political ideas. It refers to a partisan political movement, an ideological orientation, and a set of political institutions. Common denominators are the extension of democracy to socioeconomic spheres and an expansion of government activities beyond those of merely providing national security, law and order, and a narrow set of public goods. However, such a program would seem problematic given a number of insights offered by public choice theory: All forms of majority decisions are sensitive to even small changes in the procedures and are likely to produce outcomes not preferred by a majority. Majority decisions also risk producing Pareto-inferior outcomes, especially when costs can be imposed on others. And the fewer constitutional limits on government activities there are, the larger the extent of rent seeking with associated welfare losses is likely to be. Together these points are significant challenges to a program that wants to extend majority decision to new spheres while simultaneously promising prosperity for all."