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diff --git a/project/templates/stvcount.xhtml b/project/templates/stvcount.xhtml new file mode 100644 index 0000000..2cb3dda --- /dev/null +++ b/project/templates/stvcount.xhtml @@ -0,0 +1,304 @@ + +{%- extends "base.xhtml" -%} + + + +{%- block title -%}Single Transferable Vote Counter{%- endblock -%} + + + +{%- block style %} + <link href="/css/stvcount.css" rel="stylesheet" /> +{% endblock -%} + + + +{%- block content %} +<h4>Single Transferable Vote Counter</h4> + +<p>Git repository: <a href="/cgi-bin/cgit.cgi/stv-count">Link</a></p> + +<h5>19/2/2017</h5> + +<p>To give an incredibly brief summary of <a href="https://en.wikipedia.org/wiki/Parliament_of_Australia" +class="external">Australia's political system</a>, both the Federal Parliament and most of the State +Parliaments are bicameral. The lower houses are generally elected by Instant Runoff, while the upper +houses generally have half elections using Single Transferable Vote. There are exceptions and a +whole lot of differing details, but that's the overall pattern.</p> + +<p>In 2016, however, the Federal Parliament underwent a Double Dissolution, causing the entirety of +both houses to go to an election. This had the outcome of 20 out of 76 seats going to third parties +in the upper house, a record number. Even more than the 18 there were prior. As the entire purpose +of a Double Dissolution is to break deadlocks in parliament, to have the outcome go in the +<a href="http://www.abc.net.au/news/2016-07-03/crabb-election-2016-is-lose-lose-for-malcolm-turnbull/7565840" +class="external">complete opposite direction</a> probably caused some dismay from Malcolm Turnbull +and his Liberal/National government.</p> + +<p>This raises the question: Would they have been better off had a normal election happened instead? +</p> + +<p>To calculate the likely outcome, the ballot preference data is needed. That's the easy part, as +the Australian Electoral Commission makes that available +<a href="http://results.aec.gov.au/20499/Website/SenateDownloadsMenu-20499-Csv.htm" class="external"> +here</a> in the 'Formal preferences' section. Then, a program is needed to execute the STV +algorithm, which is as follows:</p> + +<ol> + <li>Set the quota of votes required for a candidate to win.</li> + <li>Allocate the ballot papers according to first preference to each of the candidates for + initial vote totals.</li> + <li>Mark any candidate who has reached or exceeded the quota as elected.</li> + <li>If any elected candidate has more votes than the quota, transfer the excess to the other + candidates according to the next applicable preference.</li> + <li>If no further candidates meet the quota, the candidate with the fewest votes is eliminated + and their votes are transferred to the others according to next applicable preference.</li> + <li>Repeat steps 3-5 until all seats are filled.</li> +</ol> + +<p>Seems simple enough, right? Except not really. There is a surprising amount of complexity in +there, and most of it is to do with how to transfer votes around. So, in addition, there are the +specifics for the version used for the Australian Senate:</p> + +<ul> + <li>Voters are given the option of voting either "above the line" or "below the line". The + latter is standard STV. The former used to be a group voting ticket, but for 2016 and later + it is treated as a shorthand way of voting, as per instructions + <a href="http://www.aec.gov.au/Voting/How_to_vote/Voting_Senate.htm" class="external">here</a>.</li> + <li>There are <a href="http://www.aec.gov.au/Elections/candidates/files/ballot-paper-formality guidelines.pdf" class="external">specific guidelines</a> on what constitutes a correctly filled + out ballot. This is important for parsing the formal preference data.</li> + <li>The <a href="https://en.wikipedia.org/wiki/Droop_quota" class="external">Droop quota</a> is + used.</li> + <li>All votes are transferred from elected candidates at a fraction of their value, as per the + <a href="https://en.wikipedia.org/wiki/Counting_single_transferable_votes#Gregory" class="external"> + Gregory Method</a>. This can result in fractions with surprisingly large numerators and + denominators. This also results in occasional discarding of fractional votes during + transfers.</li> + <li>Should the next applicable preference of a ballot be a candidate who has already been + elected, that preference is ignored and the ballot is transferred to the next preference. + </li> + <li>If the number of remaining candidates is equal to one more than the number of remaining + vacancies, the candidates with the highest vote totals at that point are considered elected. + </li> +</ul> + +<p>My implementation also includes <a href="https://en.wikipedia.org/wiki/Counting_single_transferable_votes#Bulk_exclusions" +class="external">bulk exclusions</a> using applied breakpoints in order to increase speed slightly +and minimise superfluous logging.</p> + +<p>At this point I'm fairly sure my program provides an accurate count. However, my numbers still +differ slightly from the ones provided by the AEC's official distribution of preferences. +Investigations into the exact cause are ongoing.</p> + +<h4>Results</h4> + +<p>Calculations were done for each state using the formal preference data with vacancies set to 6 +instead of 12, and the results were added to the Senators elected in 2013 to find the probable +outcome. The results for ACT and NT were taken as-is, because the few Senators elected from the +territories are not part of the half election cadence anyway.</p> + +<p>Computational resources required varied from approximately 50 seconds using 46MB of memory for +Tasmania, to nearly 30 minutes using 1452MB memory for NSW. The vast majority of that time was spent +parsing preference data, and the program is single threaded, so there is still room for improvement. +All counts were run on a Core 2 Quad Q9500.</p> + +<table> + <caption>Probable non-DD results by state</caption> + <tr> + <th colspan="2" style="width:10em;">NSW</th> + <th colspan="2" style="width:10em;">VIC</th> + <th colspan="2" style="width:10em;">QLD</th> + <th colspan="2" style="width:10em;">SA</th> + <th colspan="2" style="width:10em;">WA</th> + <th colspan="2" style="width:10em;">TAS</th> + </tr> + <tr> + <td style="background-color:#080CAB; width:8px"> </td><td>Liberal</td> + <td style="background-color:#080CAB; width:8px;"> </td><td>Liberal</td> + <td style="background-color:#1456F1; width:8px;"> </td><td>Liberal National</td> + <td style="background-color:#080CAB; width:8px;"> </td><td>Liberal</td> + <td style="background-color:#080CAB; width:8px;"> </td><td>Liberal</td> + <td style="background-color:#080CAB; width:8px;"> </td><td>Liberal</td> + </tr> + <tr> + <td style="background-color:#F00011; width:8px"> </td><td>Labor</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + </tr> + <tr> + <td style="background-color:#080CAB; width:8px"> </td><td>Liberal</td> + <td style="background-color:green; width:8px;"> </td><td>National</td> + <td style="background-color:#1456F1; width:8px;"> </td><td>Liberal National</td> + <td style="background-color:#FF6300; width:8px;"> </td><td>Xenophon</td> + <td style="background-color:#080CAB; width:8px;"> </td><td>Liberal</td> + <td style="background-color:#080CAB; width:8px;"> </td><td>Liberal</td> + </tr> + <tr> + <td style="background-color:#F00011; width:8px"> </td><td>Labor</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + <td style="background-color:#080CAB; width:8px;"> </td><td>Liberal</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + </tr> + <tr> + <td style="background-color:green; width:8px"> </td><td>National</td> + <td style="background-color:#10C25B; width:8px;"> </td><td>Green</td> + <td style="background-color:#F8F16F; width:8px;"> </td><td>One Nation</td> + <td style="background-color:#F00011; width:8px;"> </td><td>Labor</td> + <td style="background-color:#10C25B; width:8px;"> </td><td>Green</td> + <td style="background-color:#E36137; width:8px;"> </td><td>Jacqui Lambie</td> + </tr> + <tr> + <td style="background-color:#10C25B; width:8px"> </td><td>Green</td> + <td style="background-color:#002F5D; width:8px;"> </td><td>Derryn Hinch</td> + <td style="background-color:#1456F1; width:8px;"> </td><td>Liberal National</td> + <td style="background-color:#FF6300; width:8px;"> </td><td>Xenophon</td> + <td style="background-color:#080CAB; width:8px;"> </td><td>Liberal</td> + <td style="background-color:#10C25B; width:8px;"> </td><td>Green</td> + </tr> +</table> + +<table> + <caption>Probable non-DD Senate composition</caption> + <tr> + <th colspan="2" style="width:24em">Party</th> + <th style="width:9em">Seats Won</th> + <th style="width:9em">Continuing Senators</th> + <th style="width:9em">Total Seats</th> + <th style="width:9em">Difference From Actual</th> + </tr> + <tr> + <td style="background-color:#080CAB; width:8px;"> </td> + <td class="left">Liberal/National Coalition</td> + <td>17</td> + <td>15</td> + <td>32</td> + <td>+2</td> + </tr> + <tr> + <td style="background-color:#F00011; width:8px;"> </td> + <td class="left">Australian Labor Party</td> + <td>14</td> + <td>10</td> + <td>24</td> + <td>-2</td> + </tr> + <tr> + <td style="background-color:#10C25B; width:8px;"> </td> + <td class="left">Australian Greens</td> + <td>4</td> + <td>4</td> + <td>8</td> + <td>-1</td> + </tr> + <tr> + <td style="background-color:#FF6300; width:8px;"> </td> + <td class="left">Xenophon Group</td> + <td>2</td> + <td>1</td> + <td>3</td> + <td>Nil</td> + </tr> + <tr> + <td style="background-color:#E36137; width:8px;"> </td> + <td class="left">Jacqui Lambie Network*</td> + <td>1</td> + <td>1</td> + <td>2</td> + <td>+1</td> + </tr> + <tr> + <td style="background-color:#F9E518; width:8px;"> </td> + <td class="left">Liberal Democratic Party</td> + <td>0</td> + <td>1</td> + <td>1</td> + <td>Nil</td> + </tr> + <tr> + <td style="background-color:#00CCFF; width:8px;"> </td> + <td class="left">Family First Party</td> + <td>0</td> + <td>1</td> + <td>1</td> + <td>Nil</td> + </tr> + <tr> + <td style="background-color:#FFED00; width:8px;"> </td> + <td class="left">Palmer United Party*</td> + <td>0</td> + <td>1</td> + <td>1</td> + <td>+1</td> + </tr> + <tr> + <td style="background-color:gray; width:8px;"> </td> + <td class="left">Glenn Lazarus Team*</td> + <td>0</td> + <td>1</td> + <td>1</td> + <td>+1</td> + </tr> + <tr> + <td style="background-color:#191970; width:8px;"> </td> + <td class="left">Australian Motoring Enthusiast Party</td> + <td>0</td> + <td>1</td> + <td>1</td> + <td>+1</td> + </tr> + <tr> + <td style="background-color:#F8F16F; width:8px;"> </td> + <td class="left">One Nation</td> + <td>1</td> + <td>0</td> + <td>1</td> + <td>-3</td> + </tr> + <tr> + <td style="background-color:#002F5D; width:8px;"> </td> + <td class="left">Derryn Hinch's Justice Party</td> + <td>1</td> + <td>0</td> + <td>1</td> + <td>Nil</td> + </tr> +</table> + +<p>* These three parties were all part of the Palmer United Party at the 2013/2014 election, but +split up mid term.</p> + +<p>Surprisingly, these projected results <em>still</em> have 20 out of 76 seats held by third party +candidates, despite the half election putting them at a disadvantage. The number of third party +groups the Liberal/Nationals have to negotiate with to pass legislation (assuming Labor and Greens +attempt to block) equally remains unchanged.</p> + +<p>The Greens manage to do slightly worse, even though their usual position of winning the 5th or +6th seat in most states often allows them to obtain more representation than their primary vote +would otherwise support. This can't even be attributed to a bad 2013 result, as their primary vote +both then and in 2016 was nearly identical.</p> + +<p>One Nation's much reduced number of seats can be attributed to the inherent geographic bias that +any system involving electing candidates across many independent divisions has. If like-minded +voters are all in one place, they receive representation, but when the same number of voters are +spread out, they get nothing. When this effect is intentionally exploited it's called +gerrymandering, but here it's merely an artifact of electing Senators from each state separately. +One Nation's support is strongest in Queensland but is relatively diffuse. Any claims of Pauline +Hanson being <a href="http://junkee.com/malcolm-turnbull-will-probably-need-pauline-hansons-support-to-pass-any-laws/82138" class="external">one of the most powerful politicians in Australia</a> are thus +overblown.</p> + +<p>The Xenophon Group, by contrast, has the vast majority of their support concentrated in South +Australia. So the result for them remains unchanged.</p> + +<p>The most noteworthy outcomes for the question though, are that the Liberal/Nationals would have +obtained more seats, and Labor would have been in a more difficult position to block the passage of +legislation. Meaning that yes, the Liberal/National government would definitely have been better off +with a normal election.</p> + +<p>Nice job screwing over your own party, Malcolm.</p> +{% endblock -%} + + |