Topic: Burial (sinking a rival you actually like)¶
Topic hub — a cross-method view. Burial is voting a strong rival below candidates you honestly prefer less, to knock them out of a comparison they would otherwise win. Your favorite stays on top — that's what separates burial from favorite betrayal — so it feels like a free move, and the whole question is whether the count lets it pay.
The one idea to take away: burial is not Ranked Robin's private wart. It is the strategy available against any method that reads a rival's position relative to other candidates — Condorcet, Borda, and (in its score form) STAR. What differs is the price: how many voters must coordinate, how much they risk, and — for the Condorcet family — which completion rule the count uses when the burial manufactures a cycle. The method that most nearly escapes it is the one this library criticizes most, RCV-IRV — and it escapes only partly, for an unflattering reason: it doesn't read your lower ranks at all until your higher ones are eliminated, so burial can never elect your favourite. A coalition that doesn't share one is another matter, and the measurement shows burial unseating the Condorcet winner from IRV in 13–37% of structured-model elections.
In the Equal Vote taxonomy of insincere votes, burial is weak insincerity — it distorts the order of candidates you don't lead with, while favorite betrayal (strong insincerity) distorts the top of the ballot. Formally, a method is open to burial only if it fails later-no-harm: if a lower ranking can never hurt your favorite, moving a rival down can never help them either.
Which methods it works on — and where each is treated¶
| Method | Buriable? | Why | Full page |
|---|---|---|---|
| Ranked Robin / Copeland | ❌ yes — its named risk | purely ordinal: sink a rival below weaker candidates and a matchup flips, often manufacturing a cycle the record-tiebreak then settles | RR honest limits §3 · the worked pair |
| Margin-based Condorcet (Minimax, Ranked Pairs, Schulze) | ⚠️ harder | they read how much each matchup was won by, so a thin manufactured cycle is resolved on numbers the buriers can't cheaply fake | Alaska 2022, buried · Minimax |
| Borda | ❌ yes, notoriously | every rank is worth points, so burying is plain arithmetic — the classic Dark Horse | The Dark Horse |
| STAR | ⚠️ possible, rarely pays | fails later-no-harm, so scoring a strong second 0 can help your favorite reach the runoff — but the runoff can then hand the win to the candidate you buried | STAR's honest limits · criteria failures · FAQ |
| RCV-IRV (Hare) | ⚠️ harder, not immune | later-no-harm stops burial promoting your own favourite — your 3rd choice is never read while your 1st is alive, so if your favourite survives the burial changed nothing, and if they don't they couldn't have won. It does not stop a coalition with different favourites burying the Condorcet winner: each buried ballot bites when that voter's own favourite is eliminated, and the CW starves on transfers. Measured at 13–37% of structured-model elections | Which RCV-IRV? · measured |
| Approval / Score | ✅ n/a (Approval) | Approval has no order to invert; withholding support is bullet voting, a different strategy with a different cure | Approval's honest limits |
The pattern worth naming: later-no-harm and Condorcet compliance can't both be had (a small impossibility result you can feel here). IRV buys burial-resistance by ignoring most of your ballot; Condorcet methods buy the head-to-head winner by reading all of it, and pay for that with burial. STAR sits between, and pays a smaller price than either.
Runnable here — burial worked on four different methods¶
| Case | Method attacked | What it shows |
|---|---|---|
| Burial in Ranked Robin — the sincere/buried pair | Ranked Robin | 15 of 42 voters rank the Condorcet winner last, manufacture a cycle, and win the record tie (sincere · buried) — triple-checked, deterministic on both engines |
| Even Condorcet methods can be buried — Alaska 2022 | Condorcet, on real numbers | rb-j's attack on the actual Alaska special: bury Begich, manufacture a cycle. The attack's success depends entirely on the completion method — margin-based rules shrug it off, a Hare/runoff completion falls for it (buried ballots) |
| Manipulability — the textbook P₃ profile | Copeland and STAR | Zwicker's own illustration of single-voter manipulability is an attack on Copeland; the page runs the same profile against STAR, where two voters bury their 4th choice and elect their favorite, and against a milder no-burial variant |
| FairVote's white-paper burials | STAR (score burial) | the critics' own constructions, reproduced: Washington 2010 — the squeeze works on STAR, but IRV resists it — and French 2017, where every faction scores Macron 0 |
What a burial actually costs¶
Every page above lands on the same three facts, which is why this library treats burial as a real but expensive attack rather than a routine one:
- It needs a large, disciplined bloc sitting inside the victim's majorities. In the Ranked Robin pair that's 15 of 42 voters — over a third of the electorate — coordinating, with decent polling, and willing to rank a candidate they genuinely like dead last.
- It backfires when mis-aimed. Bury into the wrong cycle and you elect the buriers' third choice. In STAR the buried candidate can simply win the runoff you pushed them into.
- It leaves fingerprints. Sincere ballots showed no cycle; the buried ballots do. A cycle appearing in a race whose polling showed a clear head-to-head winner is the anomaly, and the printed round-robin table is where an auditor would catch it.
And the even-handed framing this repo keeps returning to: no method is strategy-proof — Gibbard–Satterthwaite forbids it. The honest comparison isn't "which method has no wart," it's which warts are systematic and which need a heist. Burial is a heist. Center squeeze is a Tuesday.
How much of this survives measurement — and why a single "does the sincere winner still win" rate makes very different methods look alike: formal compliance vs. strategic preservation.
Closely related: strategic voting (the four-kinds taxonomy) · the five strategic pathologies (where the Dark Horse row hides this mechanism) · center squeeze (IRV's systematic wart, the contrast case) · cycle resolution (what happens after a burial succeeds) · the Smith set. Glossary: burial (weak insincerity).
This is a topic hub (cross-method index). The authoritative write-ups live in the per-method folders linked above. See the topics index for the other topic hubs.