Pith. sign in

REVIEW 4 major objections 6 minor 1 cited by

Indices of quadratic programs over reproducing kernel Hilbert spaces for fun and profit

T0 review · 4 major / 6 minor · reviewed 2026-08-11 · deepseek-v4-flash

Pith's one-line read For quadratic programs over reproducing kernel Hilbert spaces, the maximizing measure is supported on a small boundary set, the green frontier, and the capital asset pricing model holds exactly there.

desk verdict An entertaining but unproved central theorem: the green topiary theorem is asserted without a real proof, while the rest is mostly standard convex optimization repackaged. read the letter →

arxiv 2412.18201 v1 pith:Y2SV7YK6 submitted 2024-12-24 math.OC math.CVmath.FAq-fin.PMq-fin.PR

classification math.OCmath.CVmath.FAq-fin.PMq-fin.PR MSC 30C1530C8047B3246E2291G1090C20
keywords topiaryreproducingkernelHilbertspacequadraticprogrammingembeddingofmeasuresgreenfrontiercapitalassetpricinginequalitylong-onlyportfoliomazesolving
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

The paper establishes a maximum-principle explanation for sparsity in quadratic programs over reproducing kernel Hilbert spaces, which are function spaces where point evaluation is continuous. It proves that the maximizer of the aesthetic objective $O(\mu)=\int\psi\,d\mu-\|\mu\|^2/2$, called the topiary, can be supported on a small distinguished boundary, the green frontier, and that its support lies where a certain margin function vanishes on a marginal hypersurface. Read as portfolio theory, this says optimal long-only portfolios are sparse and boundary-supported, and it yields a capital asset pricing inequality: assets outside the topiaric index underperform the line set by the topiary, with equality only on the index. It also proves an invisible index theorem: if a larger universe contains a fully diversified topiaric index, then any restricted optimal portfolio is the best Hilbert-space approximation to that invisible index. The authors demonstrate the machinery by using the topiary's gradient to find a path through a maze, interpreting the path as the invisible index navigating around obstacles.

What carries the argument

The load-bearing objects are the topiary, the aesthetic margin, and the green frontier. The topiary is the maximizer of $O(\mu)=\int\psi\,d\mu-\|\mu\|^2/2$ over probability measures on $K$; even when the carrier measure is not unique, its image in the reproducing kernel Hilbert space is unique. The aesthetic margin $\iota_\mu(x)=\psi(x)-\mu(x)-r_K$, with $r_K=\int(\psi-\mu)\,d\mu$, is the optimality witness: it is zero on the support and nonpositive on $K$. The green frontier, $\mathrm{Green}(K)=\bigcap_{U\in\mathcal{U}}M_U$, is the intersection over open dense sets of embedded measures of the points where some margin attains its supremum; it plays the role of a distinguished boundary and, by the extreme-point theorem, lies inside the extreme points of $K$ under the kernel embedding. The Green topiary theorem says a measure supported on this frontier embeds to the topiary, and the invisible index theorem is carried by the identification $\mathrm{topiary}(K_2)=\psi+r$ for a topiaric index $K_2$, which converts restricted optimization into a best-approximation problem.

What would settle it

Take a small finite set $K_2$ whose kernel vectors are linearly dependent, choose a continuous $\psi$ so that the aesthetic margin of its topiary vanishes on all of $K_2$ (making $K_2$ a topiaric index), and compute whether $\psi+r$ equals $\mathrm{topiary}(K_2)$ as an element of the Hilbert space; a nonzero difference would invalidate the identification step behind the invisible index theorem.

Watch

Extended reading notes

Core claim

The central claim is that sparsity in long-only quadratic optimization is forced by a boundary maximum principle. For a compact set $K$ and continuous function $\psi$, the unique embedded topiary $\mu$ has an aesthetic margin $\iota_\mu(x)=\psi(x)-\mu(x)-r_K$ that is nonpositive on $K$ and vanishes exactly on the topiaric index (the preimage of zero for this margin), the set where equality in the capital asset pricing inequality holds. The green frontier $\mathrm{Green}(K)$ is constructed as the intersection over open dense sets of embedded measures of the points where some margin attains its supremum; in harmonic settings it lies on the boundary of $K$. The Green topiary theorem asserts that a measure supported on $\mathrm{Green}(K)$ embeds to the same topiary as the global maximizer, so the support of an optimal portfolio lies in the intersection of the green frontier with a marginal hypersurface. The invisible index theorem then says that if $K_2$ is itself a topiaric index with topiary $\psi+r$, the topiary of any smaller $K_1$ minimizes $\|\mu-\mathrm{topiary}(K_2)\|$ over measures on $K_1$, meaning the restricted portfolio is the best approximation of an invisible fully diversified index.

Load-bearing premise

The invisible index theorem assumes that once the margin vanishes on a compact set $K_2$, the embedded topiary equals the function $\psi+r$ throughout the reproducing kernel Hilbert space; this uniqueness-of-frontier property is stated but not proved for general $K_2$, and the finance conclusion rests on it.

Editorial extensions

If this is right

  • Optimal long-only portfolios are sparse: their support lies in the green frontier intersected with a marginal hypersurface, so the efficient allocation is describable by few assets.
  • Assets not on the topiaric index underperform the capital asset pricing line: $\psi(x)-r_K\leq \beta(x)(\int\psi\,d\mu-r_K)$ with equality only on the index.
  • If a fully diversified invisible index exists in a larger universe, every restricted optimal portfolio is the best Hilbert-space approximation to it.
  • The greedy update algorithm converges in objective value at worst $O(1/n)$, so the sparse topiary is computable by simple incremental updates.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • The same boundary-support mechanism should apply to any convex quadratic program with a kernel regularizer and a compact feasible set, so sparsity of optima is a generic geometric phenomenon rather than a special feature of finance.
  • One could test the invisible index interpretation empirically: compute the topiary on a large universe, remove its support, recompute on the remainder, and check whether the new topiary approaches the old one in reproducing-kernel-Hilbert-space norm; the theorem predicts convergence whenever the uniqueness assumption holds.
  • The maze-solving demonstration suggests a deterministic path-planning algorithm: the gradient of the aesthetic objective gives a curve from an interior point to the boundary that avoids a given obstacle, and the same construction could work for any compact obstacle set with a suitable kernel.
  • If the uniqueness assumption in the invisible index theorem fails, the finance narrative would need revision, but the green-frontier sparsity claim would survive; the two claims are separable and testable.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

4 major / 6 minor

Summary. The paper studies the optimization problem O(μ)=∫ψ dμ - ½‖μ‖² over kernel-embedded measures supported on a compact set K. It defines the topiary as the maximizer, the aesthetic margin, and the topiaric index (the zero set of the margin). The main advertised results are the capital asset pricing inequality (Theorem 4.1), a Julia-Caratheodory type inequality (Theorem 4.2), the invisible index theorem (Theorem 5.1), and the Green topiary theorem (Theorem 6.2), which claims that an optimal measure can be chosen supported on the 'green frontier.' Sections 7 and 8 give greedy approximation results, finite constructability claims, and informal examples from maze solving and portfolio theory.

Significance. If established, the Green topiary theorem would give a maximum-principle explanation for sparsity in quadratic programs over kernel Hilbert spaces, with potential applications to long-only portfolio theory. The paper contains some correct variational observations: Lemma 3.2 and the subsequent first-order conditions are standard, Theorems 3.3, 4.1, and 4.2 are essentially valid KKT-type restatements, and the invisible index theorem is salvageable as a projection argument once 'topiaric index' is interpreted pointwise. However, the paper's central advertised result, Theorem 6.2, is asserted without a proof, the definition of Green(K) permits the set to be empty, and the admissible class of measures is never specified. The current manuscript therefore does not establish its main claims.

major comments (4)
  1. [Section 6, Theorem 6.2] The green topiary theorem is asserted with no proof. The only justification is the sentence 'The green topiary theorem is an immediate consequence of the effectiveness of gradient ascent given by the update inequality, Theorem 7.3.' Theorem 7.3 bounds the per-step gain O(μ_t)-O(μ) in terms of the objective gap and a denominator; it says nothing about Green(K), nor about the winning regions W_x = {μ : ι_μ(x)=sup_K ι_μ} whose nonempty interior is exactly what membership in Green(K) requires. For a fixed x, x∈Green(K) iff W_x has nonempty interior: if W_x has empty interior, its complement is an open dense U with x∉M_U; if W_x contains an open set, every open dense U meets it. The manuscript gives no argument that any x∈K has a W_x with nonempty interior, and natural examples (for instance K=[0,1] with a smooth radial kernel and ψ equal to the embedded Lebesgue measure) suggest that the topiary can have full support while every W_x has empty interior, making Green(K)=∅. Thus the advertised boundary-support theorem is not established.
  2. [Definition 3.1] The admissible class of distributions is never defined. The paper says 'over all distributions' without specifying whether these are probability measures, positive measures of fixed total mass, or signed measures. The financial interpretation requires probability measures (long portfolios with weights summing to one), and Lemma 3.2 and Theorem 7.2 use convex combinations μ+t(δ_x-μ), so the feasible set must be convex and mass-preserving. Without this hypothesis the topiary need not exist or be meaningful; for example, if no mass constraint is imposed and ψ is bounded below, the objective can be made arbitrarily large by scaling. All later theorems inherit this ambiguity.
  3. [Theorem 5.1] The proof's statement 'As K2 is an index topiary(K2)=ψ+r for some r∈R' is, taken literally, an equality in H and is generally false; what follows from K2 being a topiaric index is the pointwise identity ψ(x)-topiary(K2)(x)-r=0 for x∈K2. This pointwise identity is sufficient for the theorem, since any admissible μ on K1⊆K2 satisfies ∫topiary(K2)dμ = ∫(ψ+r)dμ. The proof should be rewritten to say this explicitly, rather than invoking an apparent equality of Hilbert-space elements that would require an unproved uniqueness-set property.
  4. [Theorems 7.8 and 7.9] The finite constructability results in Section 7.2 are not proved correctly. The 'Discussion theorem' (Theorem 7.8) says 'Take B to be the topiary of K∪{x}', but the topiary is a measure, not a subset of K; the statement requires a set B⊆K. Theorem 7.9 assumes without justification the existence of a proper subset K0 optimizing O(topiary(K0)) and then concludes from the update inequality that a higher objective on K0∪{x} contradicts maximality of topiary(K); a value higher than topiary(K0) does not itself contradict optimality on K. These claims need either corrected proofs or additional hypotheses.
minor comments (6)
  1. [Section 3] The notation r_K is used before it is defined; state explicitly that r_K = ∫(ψ-μ)dμ at the point where it is introduced.
  2. [Theorem 4.1] The displayed chain 'ψ-r_K = μ = μ/‖μ‖²(∫ψdμ-r_K)' should be an inequality on K with equality exactly on the topiaric index; as printed the first equality is false for x outside the index.
  3. [Throughout] There are numerous typographical errors: 'manucript' (p.1), 'portolio' (§1.2), 'coavariance' (p.7), 'maxmimizing' (§8.5), 'greedn' (§7.1.1), and 'the the theme' (§6). These should be corrected in revision.
  4. [Definition 6.1] Using U both for the collection of open dense sets and as the index in M_U is confusing; use a script letter such as \mathcal{U} for the collection.
  5. [Problem 3] The statement 'such that ∥·∥_H ≤ ∥·∥_H' appears to have a typo; it should presumably compare the norm of the new Hilbert space with the original norm.
  6. [Section 8.1] The maze-solving example is informal; no precise statement of the algorithm, the convergence guarantee, or the claimed path construction is given, so it is difficult to verify the advertised behavior.

Circularity Check

0 steps flagged · score 2.0 of 10

No substantive circularity: the central inequalities and index theorem are exact algebraic consequences of the paper's own definitions, while the green topiary theorem is an unproved gap rather than a circular step.

full rationale

The paper's core derivation is self-contained. Theorem 4.1 is obtained by rewriting the first-order optimality condition for the aesthetic objective: the definitions of the available topiaric rate and of the topiaric beta make the capital asset pricing inequality literally the statement that the aesthetic margin is nonpositive. Theorem 5.1 is an explicit conditional equivalence: if K2 is assumed to be a topiaric index, then by the defining identity topiary(K2)=psi+r, and substituting this into the objective on K1 turns the restricted problem into minimizing ||mu-topiary(K2)||. The paper labels the premise as an assumption, so this is a transparent algebraic consequence, not a hidden fit or a prediction smuggled in from its own conclusion. The green topiary theorem, however, is not established: after Theorem 6.2 the paper says it 'is an immediate consequence of the effectiveness of gradient ascent given by the update inequality, Theorem 7.3,' but Theorem 7.3 bounds objective increase and never mentions Green(K); no equation in the paper shows that the topiary's support lies in Green(K), which may even be empty for generic K. This is an omitted-proof/correctness gap, not circularity, because Green(K) is not defined in terms of the topiary's support and no claim reduces by construction to its own input. The few self-citations (e.g., [26], [27], [28]) are contextual references for Herglotz and Julia-Caratheodory analogies and are not load-bearing for Theorems 3.3, 4.1, 5.1, or 6.2. Thus the central derivation is independent and not circular; the score reflects only the minor, non-load-bearing self-citation and the separate proof gap, which is a correctness concern rather than a circularity concern.

Assumptions & free parameters 0 free parameters · 5 assumptions · 2 invented entities

The framework rests on standard Hilbert space facts and on several unproved assumptions: probability measures are never formally singled out; equality on a topiaric index is treated as equality of Hilbert space elements; the green frontier is assumed nonempty and support-containing; and the maze example assumes properties of the Fock kernel. No free parameters are fitted; the objective's 1/2 coefficient is a modeling choice from geometric Brownian motion.

assumptions (5)
  • domain assumption Portfolio measures are probability measures: total mass is one, used implicitly to add a constant r to the objective.
    Section 3 and Theorem 5.1 use ∫dµ=1 when identifying ψ+r with ψ up to a constant; the paper never formally restricts to probability measures in Definition 3.1.
  • ad hoc to paper For a topiaric index K2, equality of ψ+r and topiary(K2) on the index determines them as equal elements of H.
    Invoked in the proof of Theorem 5.1; not proven. Requires a uniqueness set assumption for the RKHS that is not stated.
  • ad hoc to paper The green frontier Green(K) is nonempty and contains the support of the topiary.
    Theorem 6.2 asserts this, but the proof is a one-sentence reference to the update inequality; no argument shows the intersection over M_U is nonempty or that gradient ascent selects it.
  • domain assumption The space of embedded measures is compact and the topiary exists and is unique.
    Needed for maximizers; compactness of K and continuity of ψ and kernel are enough, but uniqueness of the embedded measure relies on strict convexity of the objective.
  • domain assumption The real Fock space kernel has the property that level sets of the topiary solve mazes.
    Section 8.1 relies on properties of harmonic functions in the Fock space; no formal proof is given for the maze-avoiding path claim.
invented entities (2)
  • invisible index
    purpose: To interpret the invisible index theorem: restricted optimal portfolios approximate this larger, hypothetical index.
    Introduced in Section 5 as a 'hypothetical platonic invisible index'; no falsifiable prediction outside the framework, and the theorem reduces to the definition of the topiary as a projection.
  • green frontier
    purpose: Defined as the distinguished boundary on which optimal portfolio support is claimed to lie.
    Mathematical construct defined in Section 6; its existence and support property are asserted rather than established, with no independent handle.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Indices of quadratic programs over reproducing kernel Hilbert spaces for fun and profit." pith.science (2026). https://pith.science/paper/Y2SV7YK6

@misc{pith2026241218201,
  author       = {Pith},
  title        = {Pith review of: Indices of quadratic programs over reproducing kernel Hilbert spaces for fun and profit},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/Y2SV7YK6}},
  note         = {Machine review of arXiv:2412.18201}
}
read the original abstract

We give an abstract perspective on quadratic programming with an eye toward long portfolio theory geared toward explaining sparsity via maximum principles. Specifically, in optimal allocation problems, we see that support of an optimal distribution lies in a variety intersect a kind of distinguished boundary of a compact subspace to be allocated over. We demonstrate some of its intelligence by using it to solve mazes and interpret such behavior as the underlying space trying to understand some hypothetical platonic index for which the capital asset pricing model holds.

Figures

Figures reproduced from arXiv: 2412.18201 by the authors.

Figure 1
Figure 1. Our topiaric Julia-Caratheodory inequality says that the elements in the topiaric frontier lie on a line with slope 1, depicted in red, elements of K, depicted in brown must be below the line, whereas elements in Ω not in K may be above or below, depicted in violet. The line must intersect the ψ(y) axis at the available topiaric rate rK. Thus, the topiaric Julia-Caratheodory inequality is somewhat analogous to the c… view at source ↗
Figure 2
Figure 2. If instead we have that the remainder of Ω lies on the axis, we see that the topiary has a small in￾ner product with the market, which in interpretations as covariance gives that it is independent of the rest of the space. (One can imagine a variety of reasons for such in the securities context, innovation, new ideas, fraud, memes and so on.) 5. The invisible index theorem We can become more comfortable with both th… view at source ↗
Figure 3
Figure 3. Take our reproducing kernel to correspond to the grammian of (−3, 1), (0, 2) and (2, 1) and assume ψ = 0. Starting from a bad seed and applying the greedy algorithm, we see a chronic zig-zag-drag pattern. If we had chosen a proper intial state, the algorithm in fact halts in one step. Here, the aesthetic objective is merely the negative of the norm squared over two. Ω. Let K ⊆ Ω be a finite topiaric index. Suppose t… view at source ↗
Figures from the paper (5 more)
Figure 4
Figure 4. Figure 4: The concrete version of updating via the dis￾cussion theorem, where x is chosen to maximize the aes￾thetic margin. Here the space H is the real Hardy space on the disk. The goldenrod curve represents the set K, and the yellow part is where the aesthetic margin is neg￾a…
Figure 5
Figure 5. Figure 5: The harmonic conjugates of the approximat￾ing sequence coming from the concrete implementation of the discussion theorem. The goldenrod part is our “maze” and plot is colored by distance from the value at 0. Due to conformality, (or equivalently satisfaction of the Cau…
Figure 6
Figure 6. Figure 6: An animation of our Julia-Cartheodory the￾orem for real securities data. Data is provided with￾out warranty of correctness, and the labels have been anonymized, and is meant as a demonstration of the theorem. Specifically, it neither represents financial ad￾vice nor is…
Figure 7
Figure 7. Figure 7: Lateral suborganizations can be better than subdivisions such as manufacturing, advertising and so on as they piggyback off the risk reduction of the ambient organization. That is, groups of parallel vertically inte￾grated business pathways likely have more of a chance…
Figure 8
Figure 8. Figure 8: The no removal finite constructability theo￾rem suggests one may posess as pathway to divest from individual parts as long as one does it in a particular order. Note, however, it may be necessary to do some reallocation in the remainder, and fitness still decreases as …

Discussion (0). Continue with ORCID to comment.

Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. Positive-Allocation Companion Predictors for Nonlinear Dynamics and Their Finite-Difference Diagnostics

    math.DS 2026-07 conditional novelty 5.0 of 10

    A nonnegative, sum-to-one weighted average of past snapshots defines a companion predictor whose spectrum lies in the unit disk and includes 1 as an eigenvalue.

Reference graph

Works this paper leans on

35 extracted references · 35 canonical work pages · cited by 1 Pith paper

  1. [1]

    Physical maze solvers

    Andrew Adamatzky. Physical maze solvers. all twelve prototypes implement 1961 lee algorithm. Emergent computation: A festschrift for Selim G. Akl , pages 489–504, 2017

  2. [2]

    Agler and J.E

    J. Agler and J.E. M cCarthy. Hankel vector moment sequences and the non- tangential regularity at infinity of two variable Pick functions. Trans. Amer. Math. Soc, 366(3):1379–1411, 2014

  3. [3]

    Agler and J.E

    J. Agler and J.E. M cCarthy. Pick Interpolation and Hilbert Function Spaces . American Mathematical Society, Providence, 2002

  4. [4]

    Agler and J.E

    J. Agler and J.E. M cCarthy. Distinguished varieties. Acta Math., 194:133–153, 2005

  5. [5]

    Agler, J.E

    J. Agler, J.E. M cCarthy, and M. Stankus. Toral algebraic sets and function theory on polydisks. J. Geom. Anal. , 16(4):551–562, 2006

  6. [6]

    Agler, J.E

    J. Agler, J.E. M cCarthy, and N.J. Young. A Carath´ eodory theorem for the bidisk using Hilbert space methods. Math. Ann., 352:581–624, 2012

  7. [7]

    Agler, R

    J. Agler, R. Tully-Doyle, and N.J. Young. Boundary behavior of analytic func- tions of two variables via generalized models.Indag. Math. (N.S.), 23:995–1027, 2012

  8. [8]

    Raging bull: how to invest in the growth stocks of the 90s

    David Alger. Raging bull: how to invest in the growth stocks of the 90s . Irwin Professional Pub, 1992

Show all 35 references
  1. [9]

    The electron in the maze

    Simon Ayrinhac. The electron in the maze. Shortest Path Solvers. From Soft- ware to Wetware , pages 409–420, 2018

  2. [10]

    Positively weighted minimum-variance portfolios and the structure of asset expected returns

    Michael J Best and Robert R Grauer. Positively weighted minimum-variance portfolios and the structure of asset expected returns. Journal of Financial and Quantitative Analysis , 27(4):513–537, 1992

  3. [11]

    Bickel, J

    K. Bickel, J. E. Pascoe, and A. Sola. Derivatives of rational inner functions: ge- ometry of singularities and integrability at the boundary. Proc. London Math. Soc., 116:281–329, 2018

  4. [12]

    Level curve portraits of rational inner functions

    Kelly Bickel, James Eldred Pascoe, and Alan Sola. Level curve portraits of rational inner functions. Annali della Scuola Normale Superiore di Pisa (Classe Scienze), Serie V , 21:449–494, 2020

  5. [13]

    Common sense on mutual funds: New imperatives for the in- telligent investor

    John C Bogle. Common sense on mutual funds: New imperatives for the in- telligent investor . John Wiley & Sons, 1999

  6. [14]

    Bogle on mutual funds: New perspectives for the intelligent investor

    John C Bogle. Bogle on mutual funds: New perspectives for the intelligent investor. John Wiley & Sons, 2015

  7. [15]

    Carath´ eodory.¨Uber die Winkelderivierten von beschra¨ ankten analytischen Funktionen

    C. Carath´ eodory.¨Uber die Winkelderivierten von beschra¨ ankten analytischen Funktionen. Sitzunber. Preuss. Akad. Wiss. , pages 39–52, 1929

  8. [16]

    Central limit theorems for the Wasserstein distance between the empirical and the true distributions

    Eustasio Del Barrio, Evarist Gin´ e, and Carlos Matr´ an. Central limit theorems for the Wasserstein distance between the empirical and the true distributions. Annals of Probability, pages 1009–1071, 1999. 28 G. HUTINET AND J. E. PASCOE

  9. [17]

    Architecture, constraints, and behavior

    John C Doyle and Marie Csete. Architecture, constraints, and behavior. Pro- ceedings of the National Academy of Sciences, 108(supplement 3):15624–15630, 2011

  10. [18]

    Modern portfolio theory: Foundations, analysis, and new developments

    Jack Clark Francis and Dongcheol Kim. Modern portfolio theory: Foundations, analysis, and new developments . John Wiley & Sons, 2013

  11. [19]

    Security analysis, 1934

    Benjamin Graham. Security analysis, 1934

  12. [20]

    Positively weighted portfolios on the minimum-variance fron- tier

    Richard C Green. Positively weighted portfolios on the minimum-variance fron- tier. The Journal of Finance , 41(5):1051–1068, 1986

  13. [21]

    G. Julia. Extension nouvelle d’un lemme de Schwarz. Acta Math., 42:349–355, 1920

  14. [22]

    A new interpretation of information rate

    John L Kelly. A new interpretation of information rate. The Bell System Tech- nical Journal, 35(4):917–926, 1956

  15. [23]

    Integrability and regularity of rational functions

    Greg Knese. Integrability and regularity of rational functions. Proceedings of the London Mathematical Society , 111(6):1261–1306, 2015

  16. [24]

    Adaptive markets: Financial evolution at the speed of thought

    Andrew Lo. Adaptive markets: Financial evolution at the speed of thought . Princeton University Press, 2017

  17. [25]

    The optimization of a quadratic function subject to linear constraints

    Harry M Markowitz et al. The optimization of a quadratic function subject to linear constraints. Naval research logistics Quarterly , 3(1-2):111–133, 1956

  18. [26]

    J. E. Pascoe. The inverse problem for kernel means. preprint

  19. [27]

    J. E. Pascoe. An inductive Julia-Carath´ eodory Theorem for Pick functions in two variables. Proc. Edin. Math. Soc. , 61(3):647–660, 2018

  20. [28]

    A controlled tangen- tial julia–carath´ eodory theory via averaged julia quotients

    JE Pascoe, Meredith Sargent, and Ryan Tully-Doyle. A controlled tangen- tial julia–carath´ eodory theory via averaged julia quotients. Analysis & PDE , 14(6):1773–1795, 2021

  21. [29]

    An introduction to the theory of repro- ducing kernel Hilbert spaces , volume 152

    Vern I Paulsen and Mrinal Raghupathi. An introduction to the theory of repro- ducing kernel Hilbert spaces , volume 152. Cambridge university press, 2016

  22. [30]

    The mathematics of learning: Dealing with data

    Tomaso Poggio, Steve Smale, et al. The mathematics of learning: Dealing with data. Notices of the AMS , 50(5):537–544, 2003

  23. [31]

    A critique of the asset pricing theory’s tests part i: On past and potential testability of the theory

    Richard Roll. A critique of the asset pricing theory’s tests part i: On past and potential testability of the theory. Journal of financial economics , 4(2):129– 176, 1977

  24. [32]

    Challenge to judgment

    Paul A Samuelson. Challenge to judgment. The Journal of Portfolio Manage- ment, 1(1):17–19, 1974

  25. [33]

    Learning with kernels: support vector machines, regularization, optimization, and beyond

    Bernhard Scholkopf and Alexander J Smola. Learning with kernels: support vector machines, regularization, optimization, and beyond . MIT press, 2018

  26. [34]

    Capital asset prices: A theory of market equilibrium under conditions of risk

    William F Sharpe. Capital asset prices: A theory of market equilibrium under conditions of risk. The journal of finance , 19(3):425–442, 1964

  27. [35]

    J. Wolff. Sur une g´ en´ eralisation d’un th´ eor` eme de Schwarz.C.R. Acad. Sci. Paris, 183:500–502, 1926. Email address, Geoffrey Hutinet: ghutinet@haverford.edu Department of Mathematics, Drexel University, 3141 Chestnut St, Philadelphia, PA 19104 Email address, J. E. Pasco...

Pith tools

Reviewed August 11, 2026 · model on record in the stance chip above.