Overview

The graphs below outline the estimates for the most likely parties to fill the 11 seats that are up for election. Notably there is a large probability for between 2 and 4 minor parties (parties other than ALP, GRN or LP/NP) to be elected to the LC.

Graph Breakdown

The primary percentages indicated in the first graph below are estimates based on current polling, as well as educated guesses for the minor party primary votes. Simulations were run with reasonable vote variance, then aggregated to produce the average number of expected seats in the second graph.

For the purposes of the analysis, the Xenophon group has been given a much larger variance than any of the other parties (large or small).

The following table includes outcomes that have a greater than 0.5% chance of occuring (based on the simulations I have run). They have been normalised to 100%, but this table represents about 88% of possible outcomes.

Chance of OutcomeALPLPGRNFFXENMinor Parties
43.8%34111D4D (26.1%) / LDP (10.4%) / PUP (2.3%) / TAX (2.1%) / Mult (1.8%) / PC (1.1%)
10.9%34012D4D (8.5%) / LDP (2.4%)
8.2%34112-
1.9%34011D4D + LDP (1.1%) / D4D + PUP (0.8%)
1.9%34110D4D + PUP (1.1%) / D4D + LDP (0.8%)
8.2%44011D4D (5.0%) / LDP (2.6%) / Mult (0.6%)
2.9%44111-
3.5%44110D4D (2.4%) / LDP (1.1%)
3.5%35111-
4.4%35110D4D (3.4%) / LDP (1.0%)
3.3%35011D4D (2.5%) / LDP (0.8%)
0.7%45110-
1.5%45010D4D (0.9%) / LDP (0.6%)
1.0%24112D4D (1.0%)
4.3%33112D4D (3.3%) / LDP (1%)

Because of the high primary vote I have given the minor parties (30.2%, or 3.6 quotas), these results are skewed towards lower primary votes, and fewer seats, for the major parties. This assumption has lead to reasonable chances for the ALP and LP to both get 3 seats (in the last row), or even the ALP to get 2 seats (in the second last row). If we weaken the minor party primary vote, the percentages correspondingly move towards cases with more ALP/LP seats.

For those interested in the raw percentages I used for my calculations, you can download the .csv here.

Overview

Below we will go through party-by-party analysis, and their requirements to fulfil a seat. Although many votes will be transferred through preferences via GVT deals, any individual party's primary is highly correlated with the number of seats that party wins.

ALP & LP

The two major parties have a profile similar to each other, when considering their primary vote versus the number of seats they are likely to win. Effectively, between x + 0.5 and x + 1 quotas, the likely seat outcomes range linearly from x to x + 1 seats. Between x and x + 0.5 quotas, the excess votes are most likely transferred to another party, and the original party is likely to get only x seats. This can be seen in the following graphs. The x-axis is the number of quotas received above the line while the y-axis is the likely number of seats won for that number of primary votes.

Note that the quota is slightly more than 8.33% of the total votes cast. Regardless of preference deals any party that polls greater than 8.33% will be guaranteed a seat.

The simulation data suggest that the Liberal Party will receive slightly better preferences than the ALP, and a lower primary vote for the Liberal Party will not be as big a factor as it will be for the ALP.

The Greens

Greens preference deals appear to be neither strong nor weak. The probability of election is roughly equal to the number of primary quotas. The Greens will need strong primary polling to win a seat.

Minor Parties

Based on simulation analysis, the number of seats that are likely to go to a minor party (not ALP, GRN or LP/NP) are given in the following table. Effectively the minor parties will only win 2, 3 or 4 seats (unless something incredibly contrived occurs, or there is a massive change in the primary votes between the minors/majors).

Minor Party SeatsProbability
00%
10.6%
215.8%
362.1%
420.1%
51.4%
60.01%
70%

Of the three seats which are likely to go to a minor party, there are a few interesting contenders. The graphs below demonstrate this well by establishing which parties have a high chance of getting a seat with comparatively low primary votes.

Family First is very likely to secure a seat. Even with a very small primary vote of, say, 0.3 quotas (which they are sure to reach and exceed), their preference deals with the other parties will most likely secure themselves a seat.

Dignity for Disability has been given a fantastic position on the ballot paper (right between the major parties) and have also secured fantastic preference deals. These two factors, along with a reasonable primary vote, give them a very strong chance of election.

The Liberal Democrats, in spite of their horrible ballot placement, are a small chance to take a minor position as well. Compared with the greens, they need less primary vote for the same chance at election. However, their ballot placement will likely be their biggest obstacle.

There are a few micro parties that may harvest votes and get elected (in the same manner as the Sports Party in the recounted Half-Senate election in WA in 2013). Powerful Communities is a great example. In the fourth graph below, there is a dip in their probability, and this is due to low sampling, not a real effect. Their chance of being elected is roughly double how many quotas they receive, so they are a party to look out for as well.

Notably, the Palmer United Party has horribly poor preference deals and is unlikely to win a seat. Unless the party manages to pull very close to a quota in primary votes, they will struggle to find enough preferences to get them over the line.

Nick Xenophon's Team

This is probably the hardest vote to establish a good estimate for. There are so many reasons why Nick's team may do poorly or well. Ballot position and lack of Xenophon as a candidate are reasons it may do poorly, but correspondingly, name recognition and proximity to the Federal Election are reasons they may do well. Notably, there are only two candidates running. If, somehow, they manage to pull greater than two quotas, the excess votes will go to the Dignity for Disability candidate.

The graph below indicates that the Xenophon Team's preference deals are closer to bad than good. With a a reasonably sized over quota (0.47 excess) they're only a 15% chance to gain an extra seat. I expect that this team will receive close to, or just over, a quota and will receive one seat. However, two may be beyond them.