splitting_optima2026_submission
Splitting Paper — OPTIMA 2026 Submission Package
Target: OPTIMA 2026 (Optimization and Applications, Springer LNCS)
Dates: 22–26 September 2026, Petrovac, Budva, Montenegro
CFP status: дедлайны не опубликованы (апрель 2026); ожидается ~май (abstract), ~июнь (full)
Format: 10–15pp LNCS (conference short version of JCAM 29pp)
Grant: РНФ 23-11-00229-П — уточнить участие у Матюхина!
Title
“Stochastic Gradient Algorithms from ODE Splitting Perspective”
(авторы: Daniil Merkulov, Ivan Oseledets — Skoltech)
Conference Abstract (150 words, LNCS style)
We present a unified framework for stochastic gradient methods through the lens of operator splitting for gradient-flow ODEs. We show that one epoch of SGD is precisely a first-order Lie–Trotter splitting of the gradient-flow ODE, derive an upper bound on the global splitting error, and establish that the Kaczmarz (ART) method is the exact limiting case of unit-batch SGD for the linear least-squares problem. Replacing the standard Euler step by a higher-order local ODE solver yields a splitting optimisation scheme that is markedly more robust to step-size choice across linear, logistic, and softmax regression benchmarks. For the LASSO ($\ell_2 + \ell_1$) objective, we analyse both the first-order Lie–Trotter (ISTA) and second-order Strang splitting: the first-order scheme achieves zero asymptotic bias, whereas the Strang scheme incurs a bias floor scaling as $O(h^2\lambda^2)$. A support-characterisation conjecture for Strang-ISTA fixed points is proposed and confirmed numerically.
Keywords: stochastic gradient descent, operator splitting, Lie–Trotter, ODE methods, LASSO, ISTA, Kaczmarz method
LNCS Highlights (4 bullets — required)
- SGD reinterpreted as Lie–Trotter operator splitting of the gradient-flow ODE
- Higher-order local ODE solvers yield step-size-robust splitting optimisation scheme
- Kaczmarz method is the exact unit-batch splitting limit for linear least squares
- LASSO: Lie–Trotter ISTA achieves zero bias; Strang-ISTA has $O(h^2\lambda^2)$ bias floor
Proposed LNCS Short Version Structure (10–12pp)
| Section | Pages | Content |
|---|---|---|
| 1. Introduction | 1.5 | Problem motivation, contributions |
| 2. SGD as Splitting Scheme | 2 | Lie–Trotter derivation, Table 1 |
| 3. Global Splitting Error | 1 | Theorem + bound |
| 4. Kaczmarz as Exact Limit | 1.5 | Proposition + proof sketch |
| 5. LASSO Analysis | 2.5 | LT-ISTA vs Strang-ISTA, bias floor, Conjecture C |
| 6. Experiments | 1.5 | lin.reg + logistic + softmax (2 figures) |
| 7. Conclusion | 0.5 | |
| References | 1 | ~15 refs |
Source: collapse §§2–5 of JCAM paper; keep all 4 main results; drop extended proofs → appendix or arXiv
Action Plan
- Даниил: подтвердить у Матюхина — в гранте РНФ 23-11-00229-П?
- Следить: conf-optima.ru еженедельно — ждать появления CFP/дедлайнов
- Как только CFP появится: начать LNCS версию (~2-3 дня работы)
- Сократить JCAM 29pp → 10-12pp LNCS
- Оставить: Theorem (splitting error bound), Proposition (Kaczmarz), Theorem (Strang-ISTA bias)
- Убрать: расширенные доказательства, §§ с Conjecture B (оставить C) - arXiv preprint: выложить текущий JCAM черновик до дедлайна OPTIMA
Review Item (для Даниила)
Вопрос: Подтвердить участие в гранте РНФ 23-11-00229-П у Матюхина — нужно ли готовить OPTIMA 2026 submission?
- Если ДА: начинаем LNCS версию как только выйдет CFP (~май)
- Если НЕТ: рассмотреть другую конференцию (AIJourney ~июль)
Подготовлено: Феанор worker 17:05 MSK 9 апр 2026