Swingometer

[ciphergoth]

Paul's two dimensional three-way swingometer

This is still a draft version of the swingometer, posted here to get some feedback on how to make it more comprehensible and more useful. A three-way election is a rather challenging thing to illustrate on a diagram, so I hope you'll forgive this being a little harder to follow than a normal two-way swingometer!

• Point the mouse at the "2005" on the image and you'll see the result for 2005; the share of the vote for each party, and the number of seats they hold. Strictly speaking it's a projection of 2005's result onto the 2010 constituencies.
• Move the mouse around the diagram and you'll see projections for what sort of parliament you might see as the vote share changes. These projections are based on the very simple "Uniform National Swing" model, which has many failings but AFAICT more sophisticated models don't do much better in practice.
• The colour of each hexagon illustrates who has the most seats; a majority is shown in a darker colour. Larger majorities get darker colours. Where two parties are exactly equal, we use an in-between colour. Just compare the colour of the hexagons with the share of seats indicated for each one to understand the colour scheme.
• The straight lines across the diagram indicate the lead in points of the party with the largest vote share. Where the three lines meet is the point where all three parties get the same number of votes.
• A fixed proportion of votes are shared between the three main parties It would be better if you could change how many votes go to other parties, but it's much harder to do.

I have plans for updating this diagram during election night, but they're even more complicated, so I'll come to that later. Please let me know what you think - does it make sense?

Comments

[henry_the_cow]

I agree with much of the above. It's good. The main thing missing is some sort of labelling on the main map; currently it is like a topographical map in which the contours aren't labelled, so we don't know if we're looking at mountains or foothills.

Also, the pop-up bar chart doesn't always display the +/- from 2005. (When it does, the plus sign is too small for my old eyes to clearly distinguish from the minus sign).

As you note, polls have the problem of small parties and undecided votes. Could the size of uncertainty be indicated by circles on the main map? I suspect this would add a degree of reality to the impression that people take from these polls. You'd probably want an option to toggle it on/off though, otherwise the map would be completely swamped by opinion polls and their margins of error.

[ciphergoth.livejournal.com]

Hmm, need to clear that up - the +/- refers to the majority finishing line, not 2005. Is it worth displaying change in seats from 2005?

Gathering enough information to properly display poll uncertainty could be hard - hopefully the way the polls scatter would get that across.

[henry_the_cow]

Oh I see now. I didn't grok the meaning of the +/- at all, not the horizontal line. And I wondered why they disappeared sometimes (i.e. when they are all <-100).

This negates my comment about the size of the + sign. I was assuming, without looking too closely, or thinking, or anything, that if one number was a -, the other must be a + (because I was assuming a swing).

Ideally, these negative/positive numbers would somehow visually indicate the distance from the horizontal line, but I don't see how to achieve that, especially when the edge of the bar is close to the line.

Maybe a simpler approach would be to label the horizontal line with the number required for a majority. (I did

I agree with the suggestion of adding % signs to the upper graphic in the pop-up.

[ciphergoth.livejournal.com]

I'm labelling the line with the majority number now; I'm going to add text as drdoug suggests for the rest.

I tried adding the % signs to the upper graphic but that really doesn't look good; I've put a % in the centre of the graphic instead, which I hope does the same job but looks quite a bit nicer.