[EM] Election-Methods Digest, Vol 89, Issue 27

[capologist]

Juno wrote:

> The two seat method seemed theoretically elegant to me since it pretty much kept the current two-party ideology while providing some interesting changes to it. Also high seat numbers with full proportionality were interesting (although more complex computationally). The four seat approach may be excellent for the USA right now from the point of view that there may be appropriate number of emerging parties right now to make use of those four seats.

I think two seats per district, though a great improvement over one seat, is unnecessarily limiting in a couple of significant ways.

Imagine an example with a one-dimensional (left-to-right) political spectrum and four candidates: Leftist Extremist (LE), Leftist Moderate (LM), Rightist Moderate (RM), and Rightist Extremist (RE). The electorate is rather polarized and the preferences break down as:

   30  LE > LM > RM > RE
   15  LM > LE > RM > RE
    5  LM > RM > LE > RE
    5  RM > LM > RE > LE
   15  RM > RE > LM > LE
   30  RE > RM > LM > LE

S=2 would elect the two extremist candidates with 50 votes each (LE:50, RE:50). The extremist candidates are elected in this example because most of the population is extremist. S=3 would elect (LE:30, LM:25, RE:45) or (LE:45, RM:25, RE:30), depending which way the tie breaks. S=4 would elect (LE:30, LM:20, RM:20, RE:30). With S=3 or S=4 you get the centrist voice with enough voting support to make deals and get things done when the two extremes are unwilling to deal with each other.

Another reason for S>2, particularly in America, is the conservative libertarians who hate having to choose between a conservative Christian candidate and a liberal candidate, and rightfully so.

> If a four seat solution would be chosen I'd expect more discussion after few years when some new smaller parties would start questioning the idea of limiting the number of parties (and size of minority with right to its own representative) to that level.

Four seats per district doesn't mean a limitation on the number of parties with access to the ballot. There can be more parties than there are seats per district. Of course, that means that some voters will have to settle for a representative from a second or third choice of party, or for going unrepresented.

New smaller parties that have trouble getting elected can question the four-seat limit if they want to.  The system doesn't promise that every interest group will get its own representative in the legislature, nor is this even desirable.  (Keep in mind, these guys do more than just vote on bills.)  A voting block greater than 20% is guaranteed a seat in a four-seat district, and 5-10% will usually suffice. If your voting block is too small to elect its own representative, then you may have to settle for your favorite of the four representatives selected by the other 80%+ of the electorate (or for "none of the above"). That's not unreasonable. It's a far cry from a 49% block having to be represented by the one representative selected by the other 51%.