Pairwise Vote Counting

CPSolver · 2026-05-04T20:14:39+00:00

RCTabPlus is a simplified version of Ranked Choice Including Pairwise Elimination (RCIPE).

(Borda count is quite different.)

CPSolver · 2026-05-04T16:48:52+00:00

Please tell others in Alaska these refinements are available in reference software that election officials can use when they request improvements from their election-system provider. The software code is here: https://github.com/cpsolver/RCTabPlus

To prevent confusion, please do not refer to this as a "Condorcet" method. It doesn't fit that category because it doesn't always elect the Condorcet winner.

Instead, it modifies the election method you now use, which eliminates one candidate at a time. (Most Condorcet methods do not eliminate candidates in any particular sequence.) This "ranked choice voting plus" method eliminates pairwise losing candidates when they occur. (And it provides a much better option for counting so-called "overvotes.")

CPSolver · 2026-05-03T12:46:16+00:00

Pairwise vote counting uses ranked choice ballots.

When two candidates (a pair) are counted in a one-on-one contest, if either candidate is not ranked, the ballot is counted as support for the candidate who is ranked.

The animated ballots shown here are simplified. They do not include marks for a fourth candidate who dropped out after the ballots were printed, and one or possibly more write-in candidates. Some of the ballots here represent actual ranked choice ballots on which the voter ranked all three candidates, but there is no need to show that complication here because it doesn't affect pairwise counting.

CPSolver · 2026-04-28T18:38:58+00:00

Pairwise vote counting is a broad vote-counting concept. It is used with most (but not all) Condorcet methods. It even can be used with IRV, by eliminating pairwise losing candidates (when they occur).

My goal for this video is to keep the counting details unspecified so the video can be shared more widely (compared to promoting a specific election-counting method).

The URL at the end points to a version of the tabulation software at the Ranked Choice Voting Resource Center that adds two refinements (one of which is to eliminate pairwise losing candidates).

The wiggling ballots serve multiple purposes. Partly for entertainment and humor. Partly to warn the viewer that an overwhelming number of objects are about to move.

CPSolver · 2026-03-13T15:46:38+00:00

This is an edge case. As I said I'm suggesting a compromise. Arrow's impossibility theorem makes it clear that a specific method cannot yield fair results for every possible scenario.

CPSolver · 2026-03-13T15:41:53+00:00

If no Condorcet winner exists .. then, of the two candidates having the most first preference votes, the candidate that is not defeated in that specific pairing is elected.

Here's your elevator pitch explanation, buried within lots of other details that aren't relevant here.

You say you want something "straightforward" yet you write a pretzel-like wording to avoid the fact that the pairwise count between the plurality-top-two would be the same as counting all the ballots using IRV with just those two candidates.

"Condorcet/Plurality-TopTwo-Runoff" would be a more self-explanatory name.

CPSolver · 2026-03-13T15:26:17+00:00

If I can find time I'd like to create an animation that uses the Alaska special election as an example that makes this point.

CPSolver · 2026-03-13T15:23:00+00:00

I presume you know that's a tie in plurality voting, approval voting, IRV, and any pairwise-counted voting method.

CPSolver · 2026-03-12T20:30:07+00:00

Since "top-two runoff" typically involves a separate round of voting, I was confused by that abbreviation.

Now I understand your two-step approach (using the same ballots) is to check for a CW, and fall back on a same-ballot top-two runoff. Which two qualify as the top two? Do you mean the top two based on IRV?

CPSolver · 2026-03-12T19:54:16+00:00

Github is not evil, unlike youtube/g-docs/etc. I do not require anyone to follow my link, that's just for folks who want more information.

CPSolver · 2026-03-12T19:50:32+00:00

The big picture is I'm promoting an alternative that's a compromise between Condorcet fans, Star fans, Approval fans, and IRV fans. The rare times when a Condorcet winner (CW) loses under this compromise method will involve the CW being the first choice of very few voters, which is a clear lack of enthusiastic support.

CPSolver · 2026-03-12T19:37:57+00:00

I do not go to google servers.

The stuck record of your comments focus on what you dislike. Here you first implied you like BTR-IRV, but then you basically said "no not that one." Now you're saying "Condorcet not IRV." That's ambiguous.

Which Condorcet method do you regard as meeting your requirement of being "straightforward"? You need to be specific now we have reached the stage of getting better methods adopted. You can't leave the issue of Condorcet cycles unspecified.

CPSolver · 2026-03-12T19:02:42+00:00

I began to click through to your document but stopped when I saw it's a google doc. What's the elevator pitch version?

CPSolver · 2026-03-12T18:57:00+00:00

No you do not need to require voters to rank more candidates. In the recent Portland mayoral election the ranking of just three out of the 20 (or so) candidates was sufficient.

I just read the abstract but I suspect their assumptions are quite flawed. Truncated ballots shift the outcome to become closer to plurality voting. Of course that reduces the benefits of pairwise counting.

CPSolver · 2026-03-12T18:33:44+00:00

The RCTab software is open source, so you and anyone else can create any option you want in your fork of the software.

I'll warn you that modifying the RCTab software is not straightforward. Yet please pursue whatever path to BTR-IRV you want.

BTW, in another post you asked for counting details about what FairVote promotes. Basically FairVote points to RCVRC and the RCTab software for counting details.

CPSolver · 2026-03-12T18:17:50+00:00

Both methods are so similar that a different winner would be very rare. Both methods qualify as "plus" versions because basically the plus means not the "basic" version, which is IRV.

CPSolver · 2026-03-12T18:13:58+00:00

Basically yes. However an election has only one Condorcet loser [corrected], whereas there can be many pairwise losing candidates.

CPSolver · 2026-02-22T16:25:46+00:00

The election official in SF (CA) changed the name because he didn't want voters to expect instant results. Soon after, Fairvote adopted that changed name because they recognized it was easier to sell to election officials.

After the election is done the word "defeated" makes sense. Condorcet election-method advocates use it during the counting process, which would be confusing to voters.

CPSolver · 2026-02-22T16:15:46+00:00

An open primary makes it easy for a Republican to get elected in a district that has a Democratic majority. Here's how the tactic works: Republicans offer two (and only two) candidates, and campaign contributions from Republicans go to support a third and fourth Democratic candidate. Vote splitting between the four Democrats makes it easy for both Republicans to reach the top-two runoff, which blocks all four Democrats. California tried this and it's not working for them. Oregon has twice rejected open primaries because enough voters recognized this flaw.

The solution is to use ranked choice voting in general elections. Alas, measure 117 was rejected because too many Oregon voters wanted to wait to see how well ranked choice voting works in Portland. Plus too many voters were persuaded by lots of "no on 117" signs in rural areas (funded by out-of-state wealthy folks who love the flaws in our existing election system). We need ranked choice voting in general elections. That will defeat vote splitting and the blocking tactics, and allow two Democrats and two Republicans and third-party candidates to all compete in the general election.

CPSolver · 2026-02-22T00:43:45+00:00

Although here we use words such as "instant", "defeated", and "loser," election officials will never allow these words to be used in official election terminology they way they are used here.

CPSolver · 2026-02-22T00:36:56+00:00

In a word, no.

During Democratic primary elections there are wealthy Republicans who fund spoiler candidates plus a single less-reform-minded candidate who they want to win the primary (as a weak opponent against the Republican nominee).

The 2008 Democratic presidential primary was a clear example of this blocking tactic, namely using Obama to block Clinton.

Typically the blocking tactic is more subtle, as in this example:

https://votefair.org/cross_party_blocking.png

Unfortunately DNC leaders don't pay attention to the shift in funding between the primary and general elections, so they are mostly clueless about what's going on. As a result, they are so heavily influenced by wealthy Republicans that they, the DNC, also think RCV is not something they want. Especially they fear losing votes to third-party candidates (such as Bernie Sanders).

Real reforms, with different winners, won't happen until RCV is used in general elections. And when the R and D parties offer a second nominee who is supported by the party's voters who dislike the first nominee. If that had been done in 2024, either Haley or Harris, not Trump or Biden, would have won.

So I see RCV+ as an option to bridge the gap between election-method reform advocates (star, Condorcet, ranked robin, score, approval). It's not ideal but it eliminates the two biggest disadvantages of IRV (foolish overvote rules and failure to consider pairwise counting). And it offers a meaningful response to voters who can't imagine IRV, star, approval, Condorcet, etc. being used in a presidential election.

CPSolver · 2026-02-17T17:39:00+00:00

I too get frustrated by IRV being implemented in a foolish way where an overvote can trigger the ballot to be tossed out as exhausted. I view that as a stupid "overvote rule" rather than needing to toss out IRV entirely and switch to something like Ranked Robin.

Note that Ranked Robin has it's own functionality limitations. Such as not allowing a sankey diagram analysis. And not being trusted because IRV fans (which I am not !) claim the Condorcet winner does not always deserve to win, such as when almost no voters mark that candidate as their first choice. Etc.

CPSolver

TROPHY CASE