Fear And Loathing With Victorian Upper House Preference Flows

Following the launch of Antony Green's Legislative Council calculator I've been playing around with some possible scenarios for the Victorian upper house group ticket flows.  Quite a few people are doing this and so there are a number of different estimates about what might happen out there.  What we know from the past is to expect the unexpected - we can say that it looks like preference harvesters will win several undeserved seats, but it's hard to say which ones they will be and who.  The whole exercise is incredibly sensitive to starting assumptions - one micro-party you've never heard of might get 1% instead of 0.5% and suddenly something completely different happens.  Snowballs from very low vote shares have a higher chance of crashing because of below-the-line votes, especially as voters for micro-parties, with the exception of the Liberal Democrats, are more likely to vote below the line.  In 2014 the BTL rate for most micros was in the range 8-22%.

At the last Victorian election, five candidates won seats as a result of preference-harvesting:

* In Eastern Victoria, the Shooters, Fishers and Farmers (2.44%) beat ALP-2 (8.68% over quota) and Green (8.23%)
* In Northern Metro, the Sex Party (2.87%) beat Labor-3 (7.06% over quota)
* In Northern Victoria, the Shooters, Fishers and Farmers (3.5%) beat L-NP-3 (7.84% over quota) and Greens (7.68%)
* In Western Metro, Democratic Labour Party (2.57%) beat ALP-3 (10.65% over quota) and L-NP-2 (6.90% over quota)
* In Western Victoria, Vote 1 Local Jobs (1.28%) beat Greens (9.19%)

WA Senate Squeaker

Original Provisional Result: Pratt (ALP) and Wang (PUP) defeat Ludlam (Green) and Dropulich (Sports) by 14 votes at key exclusion.

Recount: Recount of above the line and informal votes granted Oct 10.  Recount ran from Oct 17 to Nov 1.  Various corrections were made but 1370 votes were lost, could not be rechecked, and were excluded from the recount.

Declared Result: Ludlam (Green) and Dropulich (Sports) declared winners by 12 votes at key exclusion.

But There's A Problem: The lost votes would have advantaged Pratt (ALP) and Wang (PUP) by 13 votes, meaning that if there were no errors in the counting of those votes, Pratt (ALP) and Wang (PUP) could have won by one vote.  

Where to from here? Outcome referred to Court of Disputed Returns by AEC requesting that election be ruled void.  Petitions also filed by Zhenya Wang (PUP) and Simon Mead (ALP state secretary).  The arguments for voiding the election were accepted and the election was ruled void, triggering a full WA Senate by-election to be held on April 5 under the existing system.

Updates to this post appear with the newest at the bottom.

Democracy in action! Screenshot of the critical point of the preference distribution.

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Just a post to explain what is going on with the Western Australian Senate count to those not already aware of it.  The button was pressed today on the most exciting of the eight Senate post-counts.

Through the complex process of modelling the outcome undertaken by Truth Seeker, Antony Green and others, one point of the long list of exclusions of minor candidates became increasingly crucial and incredibly close.  That point concerned which of the Shooters and Fishers and the Australian Christians was excluded first.  Neither of these parties had the slightest chance of winning, but because of their different group voting ticket preferences, which one was excluded first would have a great impact on the outcome.  If the Australian Christians were excluded, this would then lead to the exclusion of the Sports Party's Wayne Dropulich, and this would in turn result in Labor's Louise Pratt and Palmer United Party's Zhenya Wang getting the final two seats.  If the Shooters and Fishers were excluded, this would then lead to Dropulich winning on a preference snowball and taking the Greens' Scott Ludlam with him.

The Shooters and Fishers had a lead on the ABC Calculator, but it assumes all votes are above the line votes, and ignores the impact of below the line votes that do not follow the script.  If only reliably "locked in" votes (ticket votes and a share of votes from a party's second and subsequent candidates) were included then the Christians had a wafer-thin lead.  But modelling by Truth Seeker here suggested that the Shooters and Fishers were slightly more likely than not to do just well enough on below-the-lines from other parties to beat the Christians at this point.  The final Truth Seeker projected margin was 54 votes to S+F, but with a large degree of uncertainty, such that "Is this significantly different to zero? No."

2013 Federal Election Late Counting: Tasmania Senate

Tasmania Senate: Current Assessment
2 Labor, 2 Liberal, 1 Green certain
Final seat between PUP, Liberal, Sex Party
Current assessment: All three parties have realistic chances.  There is no clear favourite, but PUP are in my view narrowly the best placed. 

The AEC currently expects to declare the result (subject to challenges) at 2 pm Thursday.  The button is expected to be pressed on Wednesday 10 am. 


Final Result Thread: Final result and analysis will be posted on the new thread here.


NB A report published on Tasmanian Times (18 Sep) claiming the Sex Party has won was a bad case of premature ejaculation.  Counting has not finished, the button has not been pressed yet and the ABC Calculator is not an exact model of what happens when it does. TT has since acknowledged the unclarities in the situation.

Summary: 

I have added this summary (which will be edited as needed) because this article is getting very long and very complex.  What follows below is my full analysis of the current Tasmanian Senate late count, some of which is highly technical in nature.  The current situation is that three different parties - first Palmer United, then the Liberals, then the Sex Party, have been shown as leading on the ABC Senate Calculator at various points.  However the calculator assumes all votes are above-the-line ticket votes, and in practice preferences flow slightly more weakly than the model expects, especially if a party has lots of below-the-line votes.