d4-journals-mss-2019-0052

· ? (d4-journals-mss-2019-0052)

no mirror
paperd4-journals-mss-2019-0052
authors—
venue?
filed underunclassified
judged bygpt-6-luna / xhigh (triple__luna__xhigh__c6r1)
judge confidencehigh
authors would recognise ityes

Why no mirror

The paper’s numbered results characterize geometric relationships among allowed coalitions, but none states a computational guarantee or hardness result. Section 3 describes computational procedures, yet they are not established as numbered computational results. The proposed weighted enumeration is a coherent follow-on, but it cannot supply the missing named anchor.

fails bit a — no named computational result to mirror

What the mirror covers

The candidate covers Section 3.1’s EDP coalition enumeration, supported by Proposition 2.4’s geometric characterization. It leaves the SOI and TIOLI procedures, the cross-model comparison, and the empirical illustrations without a computational mirror.

Open questions for a prover

The case FOR (proponent)

I cannot give this a qualifying named anchor under your rule. The paper proves no numbered result stating a computational problem is in P, NP-hard, or otherwise classified by complexity. Section 3 gives procedures for computing coalitions, but those procedures are not stated as numbered results and do not establish general complexity bounds. In particular, its grid methods for SOI and TIOLI are explicitly approximate.

The closest named results are Proposition 2.4 and Theorem 2.6, both proved in the paper. Proposition 2.4 says that, in dimension \(d\), the EDP-allowed coalitions are exactly those whose ideal points can be strictly separated from the remaining ideal points by a hyperplane. Theorem 2.6 says that, in every dimension, EDP and SOI allow exactly the same coalitions, and both allow every TIOLI coalition, while TIOLI also allows some coalitions that EDP and SOI do not. These are geometric characterizations, not complexity results, so neither can honestly serve as an anchor under the requested standard.

There is nevertheless a plausible, narrowly scoped mirror one could pose as follow-on work: Weighted EDP Coalition Enumeration. An instance is a finite support of ideal-point types \((v_t,\mu_t)\), where \(v_t\in\mathbb{Q}^2\), \(\mu_t>0\) is a binary rational, and \(\sum_t\mu_t=1\). Each type represents a fraction of voters who share the same ideal point and thus vote alike under EDP. The task is to return every support subset \(S\) for which some line strictly separates the points in \(S\) from those outside it, together with its mass \(\sum_{t\in S}\mu_t\) and a witnessing line. Equivalently, the witness can be represented by two outcome locations whose perpendicular bisector induces that partition. This is an enumeration problem, as in the paper’s EDP computation; it adds no optimization objective.

A plausible regime is a large electorate deciding between two policy outcomes, with many voters sharing each of a modest number \(\tau\) of ideal-point types. Then the population size \(N\) can be much larger than \(\tau\). That scenario fits the paper’s generic voter and binary-outcome setup better than a nine-member Court does. The paper’s coalition question is exactly the underlying geometric question, so its authors could plausibly recognize the weighted version as a population mirror. I would expect this fixed two-dimensional version to be tractable by enumerating halfspace-induced partitions; that expectation comes from the geometry, not from a complexity result in this paper. A natural next question is whether the corresponding TIOLI enumeration, using outcome disks, has a similarly clean weighted treatment.

The scope would be only the paper’s computation of allowed EDP coalitions in Section 3.1, supported by Proposition 2.4’s characterization. The weakest point is decisive for grading: that computational task is described procedurally, not established by a named computational result of the kind you require. Also, the nine-justice example is not a high-multiplicity regime, and replacing it with a clustered mass electorate changes the empirical setting. So this is a credible research direction, but it cannot be presented as a strong anchored case for a continuous mirror of a named complexity result in this paper.

The case AGAINST (opponent, writing after the proponent)

The decisive problem is that this paper has no numbered computational result to mirror. Proposition 2.4 characterizes EDP coalitions geometrically, and Theorem 2.6 compares the coalitions allowed by EDP, SOI, and TIOLI. Neither classifies the complexity of a computational problem. Section 3 gives procedures for particular computations: a point-pair method for the nine-justice, \(5\)-to-\(4\) case; grid approximations for SOI and TIOLI; and a connection to higher-order Voronoi diagrams. Those are computational contents, but they do not establish a complexity result in the programme’s sense.

The proposed weighted EDP enumeration is the closest follow-on. A large electorate with many voters sharing each of \(\tau\) ideal-point types is a plausible high-multiplicity setting; the Supreme Court’s nine individually distinct justices are not the only scenario available. But under EDP, the separable subsets are determined by the support coordinates. The masses \(\mu_t\) let us report each subset’s population share; they do not determine which subsets a line can separate. So the suggested computation remains an enumeration of geometric partitions of a finite point set, with a mass sum attached. It may be a coherent weighted computational-geometry question, but it is not an anchored mirror of a named complexity result in this paper.

The strongest upgrade would make mass affect the computation—for example, asking which separable coalitions have more than half the population, or how much mass must change for a vote to flip. Those could be meaningful new questions. The first adds a weighted-majority filter to the paper’s enumeration; the second adds a change or cost model that the paper does not specify. Either might be worth pursuing on its own, but neither repairs the absence of a computational result here. The same issue applies to continuous versions of Theorem 2.6: one could study the mass spectrum of coalitions allowed by each model, but that extends a geometric characterization rather than mirrors a complexity classification.

This is a strong case against accepting the proposed mirror as a qualifying anchor. Its weak point is the universal claim: the paper’s geometric setup could inspire worthwhile weighted-range or robustness research. I cannot honestly rule out such a project. I can say that calling it a continuous mirror of this paper’s named computational result overstates what the paper proves; it proves no such result.

The adversarial triple: the proponent anchors on up to three named results; the opponent sees that case and must defeat every anchor; the judge decides which case convinced it. These are the pipeline’s own outputs, generated by tools/triple_run.py — no human edited them. The paper’s own text is not reproduced here beyond the quoted statement above.