pith. sign in

arxiv: 1907.06173 · v1 · pith:DXRRG5DSnew · submitted 2019-07-14 · 💻 cs.LG · cs.DS· stat.ML

The FAST Algorithm for Submodular Maximization

Pith reviewed 2026-05-24 21:43 UTC · model grok-4.3

classification 💻 cs.LG cs.DSstat.ML
keywords submodular maximizationmonotone submodular functionscardinality constraintapproximation algorithmsadaptive algorithmsquery complexityFAST algorithmpractical runtime
0
0 comments X

The pith

The FAST algorithm achieves an approximation ratio arbitrarily close to 1-1/e for monotone submodular maximization under cardinality constraint k with O(log n log²(log k)) adaptivity and O(n log log k) queries.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper presents the FAST algorithm for maximizing a monotone submodular function under a cardinality constraint of size k. It reaches an approximation ratio that can be made arbitrarily close to 1-1/e while requiring only O(log n log²(log k)) adaptive rounds and O(n log log k) total queries. The design keeps non-asymptotic constants small, unlike earlier methods whose guarantees come with large hidden factors that make them impractical. Experiments on large data sets show FAST runs orders of magnitude faster than prior algorithms, including hyper-optimized parallel versions of state-of-the-art serial methods.

Core claim

FAST attains an approximation ratio arbitrarily close to 1-1/e for monotone submodular maximization under cardinality constraint k. It does so with O(log(n) log²(log k)) adaptivity and O(n log log(k)) queries in total. The algorithm is designed to be efficient both in its non-asymptotic worst-case query complexity and number of rounds and in its practical runtime, outperforming any algorithm for submodular maximization the authors are aware of on large data sets.

What carries the argument

Fast Adaptive Sequencing Technique (FAST), which sequences adaptive queries to reduce the number of rounds and total function evaluations while preserving the near-optimal approximation guarantee.

Load-bearing premise

The non-asymptotic query and round complexities hold without large hidden constants or implementation overheads that would negate the stated advantages over prior methods.

What would settle it

Running FAST and prior algorithms on a large dataset and measuring that the runtime difference is not orders of magnitude or that actual query counts exceed the claimed O(n log log k) bound by a large factor.

read the original abstract

In this paper we describe a new algorithm called Fast Adaptive Sequencing Technique (FAST) for maximizing a monotone submodular function under a cardinality constraint $k$ whose approximation ratio is arbitrarily close to $1-1/e$, is $O(\log(n) \log^2(\log k))$ adaptive, and uses a total of $O(n \log\log(k))$ queries. Recent algorithms have comparable guarantees in terms of asymptotic worst case analysis, but their actual number of rounds and query complexity depend on very large constants and polynomials in terms of precision and confidence, making them impractical for large data sets. Our main contribution is a design that is extremely efficient both in terms of its non-asymptotic worst case query complexity and number of rounds, and in terms of its practical runtime. We show that this algorithm outperforms any algorithm for submodular maximization we are aware of, including hyper-optimized parallel versions of state-of-the-art serial algorithms, by running experiments on large data sets. These experiments show FAST is orders of magnitude faster than the state-of-the-art.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

1 major / 0 minor

Summary. The paper introduces the Fast Adaptive Sequencing Technique (FAST) for monotone submodular maximization under a cardinality constraint k. It claims an approximation ratio arbitrarily close to 1-1/e, O(log n log²(log k)) adaptivity, O(n log log k) total queries, and practical runtime outperformance by orders of magnitude over prior algorithms (including hyper-optimized parallel versions) on large datasets, attributing the practicality to small non-asymptotic constants unlike previous methods whose bounds involve large polynomials in precision parameters.

Significance. If the non-asymptotic query/round bounds hold with small leading constants and the experimental speedups are reproducible, the work would be significant for making near-optimal submodular maximization practical at large scale, directly addressing the gap between asymptotic theory and deployable algorithms in the field.

major comments (1)
  1. [Abstract] Abstract: the central practicality claim rests on FAST having 'extremely efficient' non-asymptotic query and round complexity with constants small enough to yield orders-of-magnitude speedups, yet the abstract supplies no explicit expansion of the O(n log log k) and O(log n log²(log k)) expressions (e.g., dependence on the precision parameter needed for (1-1/e-ε) approximation) that would allow verification that these constants are indeed smaller than the 'very large constants and polynomials' attributed to prior work.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for their detailed review and constructive suggestion regarding the abstract. We address the major comment below.

read point-by-point responses
  1. Referee: [Abstract] Abstract: the central practicality claim rests on FAST having 'extremely efficient' non-asymptotic query and round complexity with constants small enough to yield orders-of-magnitude speedups, yet the abstract supplies no explicit expansion of the O(n log log k) and O(log n log²(log k)) expressions (e.g., dependence on the precision parameter needed for (1-1/e-ε) approximation) that would allow verification that these constants are indeed smaller than the 'very large constants and polynomials' attributed to prior work.

    Authors: We agree that the abstract would benefit from greater explicitness on the dependence on the approximation parameter ε to allow direct verification of the non-asymptotic constants. The body of the paper (Theorems 1 and 2, and the analysis in Sections 3–4) provides the full bounds, which incorporate only mild (logarithmic) dependence on 1/ε together with small leading constants that do not grow as large polynomials in the precision parameter. To address the referee’s concern, we will revise the abstract to include a concise statement of this dependence while preserving the high-level asymptotic claims. revision: yes

Circularity Check

0 steps flagged

No circularity: new algorithmic construction with independent guarantees

full rationale

The paper introduces FAST as a novel algorithm whose approximation ratio, adaptivity, and query complexity are derived from its explicit design and analysis rather than any self-definition, fitted inputs renamed as predictions, or load-bearing self-citations. The abstract and claims present these bounds as consequences of the algorithm's construction, with no equations reducing the stated O(log n log²(log k)) adaptivity or O(n log log k) queries to prior results by the authors. External benchmarks and practical experiments are invoked as independent validation, keeping the central claims self-contained.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on the standard domain assumption that the objective is monotone and submodular; no free parameters, invented entities, or additional axioms are stated in the abstract.

axioms (1)
  • domain assumption The objective function is monotone and submodular
    This is the standard setting for the cardinality-constrained maximization problem stated in the abstract.

pith-pipeline@v0.9.0 · 5716 in / 1252 out tokens · 31685 ms · 2026-05-24T21:43:03.627162+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.