Online Convex Programming and Generalized Infinitesimal Gradient Ascent

Martin A. Zinkevich

article2003ICML2,834 citationsClassic Paper Prize

Introduces online convex programming alongside a projected gradient descent algorithm that guarantees $O(\sqrt{T})$ regret against arbitrary sequences of convex cost functions and proves universal consistency in repeated games.

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The article addresses online optimization problems where a decision maker must repeatedly choose a point inside a known convex feasible set before observing the convex cost function for that round. Such settings arise in production planning, resource allocation, and repeated games, where future costs or payoffs remain unknown at decision time. The work introduces online convex programming to capture these repeated decisions and develops a practical algorithm to keep long-run average performance close to the best fixed choice that could have been made with full hindsight.

The article sets out to design and analyze a gradient-based method that works for arbitrary sequences of convex cost functions and to show that the method generalizes infinitesimal gradient ascent to establish universal consistency in repeated games. It defines the Greedy Projection algorithm, which performs a gradient step and then projects the result back onto the feasible set. The analysis compares performance against the single best fixed point in hindsight and derives explicit regret bounds under standard assumptions of bounded diameter and bounded gradients.

When the learning rate is set to the square root of the inverse time step, the cumulative regret grows at most on the order of the square root of the time horizon. Consequently, the average regret per round tends to zero. The same framework yields a lazy-projection variant with comparable guarantees and a dynamic-regret bound that remains controlled when the comparator sequence changes slowly. The approach is then specialized to repeated games, producing the Generalized Infinitesimal Gradient Ascent (GIGA) algorithm that inherits the regret bound and is proven universally consistent even against adaptive opponents.

These results matter because they supply a simple, widely understood techniquegradient descent with projectionthat solves a broader class of online problems than traditional experts algorithms and can achieve tighter bounds when the geometry of the feasible set is favorable. The work also clarifies how experts methods can be converted into online linear-programming solvers, though the resulting bounds may be weaker. Decision makers gain a concrete, implementable procedure that guarantees sublinear regret without requiring advance knowledge of the cost sequence.

The article recommends extending the method to non-Euclidean geometries and stronger adaptive schemes such as WoLF. Further empirical validation on larger repeated games and industrial planning instances would strengthen before widespread deployment. The main limitations are the assumptions of a closed bounded feasible set, differentiable costs, and known gradient oracles; performance guarantees weaken when these conditions are relaxed or when gradient norms are large.

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Abstract

Convex programming involves a convex set Fℝⁿ and a convex function c : F. The goal of convex programming is to find a point in F which minimizes c. In this paper, we introduce online convex programming. In online convex programming, the convex set is known in advance, but in each step of some repeated optimization problem, one must select a point in F before seeing the cost function for that step. This can be used to model factory production, farm production, and many other industrial optimization problems where one is unaware of the value of the items produced until they have already been constructed. We introduce an algorithm for this domain, apply it to repeated games, and show that it is really a generalization of infinitesimal gradient ascent, and the results here imply that generalized infinitesimal gradient ascent (GIGA) is universally consistent.

Table of Contents

  • 1 Introduction
  • 2 Online Convex Programming
  • 2.1 Analyzing the Performance of the Algorithm
  • 2.2 Regret Against a Dynamic Strategy
  • 2.3 Lazy Projection
  • 3 Generalized Infinitesimal Gradient Ascent
  • 3.1 Repeated Games
  • 3.2 Oblivious Deterministic Environments
  • 3.3 Formulating a Repeated Game as an Online Linear Program
  • 3.4 Self-Oblivious Behavior
  • 3.5 Lazy Projection and Fictitious Play
  • 4 Converting Old Algorithms
  • 4.1 Formal Definitions
  • 4.2 Converting an OLPA to an Online Convex Programming Algorithm
  • 5 Related Work
  • 6 Conclusions and Future Work
  • Acknowledgements
  • References
  • A Proof of Dynamic Bounds
  • B Proof of Lazy Projection
  • B.1 A Motivating Example
  • B.2 Geometric Lemmas
  • B.3 Completing the Proof
  • C Proof of Universal Consistency

Knowls

  1. Knowl 1 — Online Convex Programming and Regret

    definition

    An online convex programming (OCP) problem is defined over a non-empty, closed, and bounded convex feasible set FRnF \subset \mathbb{R}^n with Euclidean diameter: F=maxx,yFxy2\|F\| = \max_{x,y \in F} \|x - y\|_2

    The optimization proceeds in discrete rounds t=1,2,t = 1, 2, \dots:

    1. At each step tt, the online algorithm selects a vector xtFx^t \in F.
    2. The environment subsequently reveals a convex cost function ct:FRc^t : F \to \mathbb{R}, which is differentiable with bounded gradient norm ct(x)2c=supxF,t1ct(x)2\|\nabla c^t(x)\|_2 \le \|\nabla c\| = \sup_{x \in F, t \ge 1} \|\nabla c^t(x)\|_2 (or subdifferentiable with a computable subgradient gtg^t).
    3. The algorithm incurs cost ct(xt)c^t(x^t).

    The total cost incurred by an algorithm AA up to time horizon TT is: CA(T)=t=1Tct(xt)C_A(T) = \sum_{t=1}^T c^t(x^t)

    The cost of any fixed static comparator xFx \in F is Cx(T)=t=1Tct(x)C_x(T) = \sum_{t=1}^T c^t(x).

    The regret (static regret) of algorithm AA with respect to the optimal single static decision in hindsight is: RA(T)=CA(T)minxFCx(T)=t=1Tct(xt)minxFt=1Tct(x)R_A(T) = C_A(T) - \min_{x \in F} C_x(T) = \sum_{t=1}^T c^t(x^t) - \min_{x \in F} \sum_{t=1}^T c^t(x) An algorithm is no-regret (or Hannan consistent) if lim supTRA(T)T0\limsup_{T \to \infty} \frac{R_A(T)}{T} \le 0.

  2. Knowl 2 — Static Regret Bound for Greedy Projection

    theoretical result

    Let FRnF \subset \mathbb{R}^n be a closed, bounded, non-empty convex feasible set with diameter F=maxx,yFxy2\|F\| = \max_{x,y \in F} \|x - y\|_2, and let {c1,c2,}\{c^1, c^2, \dots\} be an arbitrary sequence of convex cost functions with gradient norms bounded by c=supxF,t1ct(x)2\|\nabla c\| = \sup_{x \in F, t \ge 1} \|\nabla c^t(x)\|_2.

    If the Greedy Projection algorithm is executed with step sizes ηt=t1/2\eta_t = t^{-1/2} for t1t \ge 1, then for any time horizon T1T \ge 1, the static regret RG(T)=t=1Tct(xt)minxFt=1Tct(x)R_G(T) = \sum_{t=1}^T c^t(x^t) - \min_{x^* \in F} \sum_{t=1}^T c^t(x^*) is bounded by: RG(T)F2T2+(T12)c2R_G(T) \le \frac{\|F\|^2 \sqrt{T}}{2} + \left(\sqrt{T} - \frac{1}{2}\right) \|\nabla c\|^2

    As a consequence, the average regret approaches zero: lim supTRG(T)T0\limsup_{T \to \infty} \frac{R_G(T)}{T} \le 0 yielding a worst-case regret of order O(T)O(\sqrt{T}) against an arbitrary sequence of convex cost functions.

  3. Knowl 3 — Greedy Projection Algorithm for Online Convex Programming

    algorithm

    The Greedy Projection algorithm (online projected gradient descent) updates its decision at each round by performing a gradient step along the cost function revealed at that round and projecting the updated vector back onto the feasible set.

    Let FRnF \subset \mathbb{R}^n be a closed convex set and P:RnFP: \mathbb{R}^n \to F be the Euclidean projection operator defined by P(y)=argminxFxy2P(y) = \arg\min_{x \in F} \|x - y\|_2.

    Input: Feasible convex set FF, sequence of learning rates {ηt}t1\{\eta_t\}_{t \ge 1}
    Output: Decisions xtFx^t \in F at each time step tt
    Initialize x1Fx^1 \in F arbitrarily
    for t=1,2,t = 1, 2, \dots do
        Play xtx^t
        Receive convex cost function ctc^t (or its gradient ct(xt)\nabla c^t(x^t))
        Compute xt+1=P(xtηtct(xt))x^{t+1} = P(x^t - \eta_t \nabla c^t(x^t))
    end for

    At each step tt, the algorithm takes the gradient ct(xt)\nabla c^t(x^t), steps by ηtct(xt)-\eta_t \nabla c^t(x^t), and projects the resulting point back onto FF using Euclidean projection.

  4. Knowl 4 — Dynamic Regret Bound for Greedy Projection

    theoretical result

    The performance of Greedy Projection can be bounded against a time-varying sequence of decisions. For any sequence of vectors (x1,,xT)FT(x^1, \dots, x^T) \in F^T, its path length is: PathLength(x1,,xT)=t=1T1xtxt+12\text{PathLength}(x^1, \dots, x^T) = \sum_{t=1}^{T-1} \|x^t - x^{t+1}\|_2 Let A(T,L)\mathcal{A}(T, L) be the set of comparator sequences of length TT with path length at most LL: A(T,L)={(z1,,zT)FT  |  t=1T1ztzt+12L}\mathcal{A}(T, L) = \left\{ (z^1, \dots, z^T) \in F^T \;\middle|\; \sum_{t=1}^{T-1} \|z^t - z^{t+1}\|_2 \le L \right\} The dynamic regret of an algorithm AA against A(T,L)\mathcal{A}(T, L) is: RA(T,L)=t=1Tct(xt)min(z1,,zT)A(T,L)t=1Tct(zt)R_A(T, L) = \sum_{t=1}^T c^t(x^t) - \min_{(z^1, \dots, z^T) \in \mathcal{A}(T, L)} \sum_{t=1}^T c^t(z^t)

    If the Greedy Projection algorithm is run with a fixed learning rate η>0\eta > 0, its dynamic regret satisfies: RG(T,L)7F24η+LFη+Tηc22R_G(T, L) \le \frac{7\|F\|^2}{4\eta} + \frac{L \|F\|}{\eta} + \frac{T \eta \|\nabla c\|^2}{2} where F=maxx,yFxy2\|F\| = \max_{x,y \in F} \|x - y\|_2 and c=supxF,t1ct(x)2\|\nabla c\| = \sup_{x \in F, t \ge 1} \|\nabla c^t(x)\|_2.

  5. Knowl 5 — Regret Bound and Universal Consistency of GIGA

    theoretical result

    In a repeated normal-form game with player action set A={1,,n}A = \{1, \dots, n\}, opponent action set YY, and utility function u:A×YRu : A \times Y \to \mathbb{R}, define the utility span: u=max(a,y)A×Yu(a,y)min(a,y)A×Yu(a,y)|u| = \max_{(a,y) \in A \times Y} u(a, y) - \min_{(a,y) \in A \times Y} u(a, y) The simplex feasible set F=Δ(A)F = \Delta(A) has diameter F2\|F\| \le \sqrt{2}, and the utility gradient norm satisfies cAu\|\nabla c\| \le \sqrt{|A|}|u|.

    When Generalized Infinitesimal Gradient Ascent (GIGA) uses step sizes ηt=t1/2\eta_t = t^{-1/2}, its expected regret with respect to any fixed pure action aAa \in A against any oblivious deterministic environment ρ:HΔ(Y)\rho : H \to \Delta(Y) over TT rounds is bounded by: EhFσ,ρ[Ra(hT)]T+(T12)Au2\mathbb{E}_{h \in \mathcal{F}_{\sigma, \rho}} [R^{* \to a}(h|T)] \le \sqrt{T} + \left(\sqrt{T} - \frac{1}{2}\right) |A| |u|^2

    Because GIGA is a self-oblivious behavior (meaning its mixed strategy at round tt depends strictly on the opponent's historical action sequence and not on its own past sampled actions), achieving sublinear expected regret against oblivious deterministic environments guarantees that GIGA is universally consistent: for every ϵ>0\epsilon > 0, there exists TT such that against any (including arbitrary and adaptive) environment ρ\rho: PrhFσ,ρ[t>T,  R(ht)t>ϵ]<ϵ\Pr_{h \in \mathcal{F}_{\sigma, \rho}}\left[ \forall t > T, \; \frac{R(h|t)}{t} > \epsilon \right] < \epsilon

  6. Knowl 6 — Generalized Infinitesimal Gradient Ascent (GIGA) for Repeated Games

    algorithm

    The Generalized Infinitesimal Gradient Ascent (GIGA) algorithm applies online convex optimization to repeated games with arbitrary finite action sets.

    Let A={1,,n}A = \{1, \dots, n\} be the player's action set, YY be the opponent's action set, and u:A×YRu: A \times Y \to \mathbb{R} be the utility function. The mixed strategy space is the (n1)(n-1)-dimensional simplex F=Δ(A)={xRnxi0,i=1nxi=1}F = \Delta(A) = \{x \in \mathbb{R}^n \mid x_i \ge 0, \sum_{i=1}^n x_i = 1\}. The projection operator is P(y)=argminxΔ(A)xy2P(y) = \arg\min_{x \in \Delta(A)} \|x - y\|_2.

    Input: Action set A={1,,n}A = \{1, \dots, n\}, sequence of step sizes {ηt}t1\{\eta_t\}_{t \ge 1}
    Output: Action choices atAa_t \in A at each round tt
    Initialize x1Δ(A)x^1 \in \Delta(A) arbitrarily
    for t=1,2,t = 1, 2, \dots do
        Sample and play action iAi \in A with probability xitx^t_i
        Observe opponent action ht,2Yh_{t,2} \in Y
        for each iAi \in A do
            yit+1=xit+ηtu(i,ht,2)y^{t+1}_i = x^t_i + \eta_t u(i, h_{t,2})
        end for
        Compute xt+1=P(yt+1)x^{t+1} = P(y^{t+1})
    end for

    GIGA uses gradient ascent on the linear utility function induced by the opponent's observed action, followed by Euclidean projection onto the probability simplex.

  7. Knowl 7 — Lazy Projection Algorithm for Online Convex Programming

    algorithm

    The Lazy Projection algorithm maintains an unconstrained state vector ytRny^t \in \mathbb{R}^n that accumulates negative gradient steps directly in Euclidean space without intermediate projections, mapping to the feasible set FF only when outputting the current decision.

    Let FRnF \subset \mathbb{R}^n be a closed convex set and P(y)=argminxFxy2P(y) = \arg\min_{x \in F} \|x - y\|_2 be the Euclidean projection operator.

    Input: Feasible convex set FF, sequence of learning rates {ηt}t1\{\eta_t\}_{t \ge 1}
    Output: Decisions xtFx^t \in F at each time step tt
    Initialize x1Fx^1 \in F arbitrarily, and set y1=x1y^1 = x^1
    for t=1,2,t = 1, 2, \dots do
        Play xtx^t
        Receive convex cost function ctc^t (or its gradient ct(xt)\nabla c^t(x^t))
        Compute yt+1=ytηtct(xt)y^{t+1} = y^t - \eta_t \nabla c^t(x^t)
        Compute xt+1=P(yt+1)x^{t+1} = P(y^{t+1})
    end for

    Unlike Greedy Projection, the unprojected vector yty^t does not restart from the boundary projection xtx^t on each round.

  8. Knowl 8 — Regret Bound for Lazy Projection

    theoretical result

    Let FRnF \subset \mathbb{R}^n be a closed, bounded, non-empty convex feasible set with diameter F=maxx,yFxy2\|F\| = \max_{x,y \in F} \|x - y\|_2, and let {c1,c2,}\{c^1, c^2, \dots\} be an arbitrary sequence of convex cost functions with c=supxF,t1ct(x)2\|\nabla c\| = \sup_{x \in F, t \ge 1} \|\nabla c^t(x)\|_2.

    When Lazy Projection is run with a fixed learning rate η>0\eta > 0, its static regret RL(T)=t=1Tct(xt)minxFt=1Tct(x)R_L(T) = \sum_{t=1}^T c^t(x^t) - \min_{x^* \in F} \sum_{t=1}^T c^t(x^*) satisfies: RL(T)F22η+Tηc22R_L(T) \le \frac{\|F\|^2}{2\eta} + \frac{T \eta \|\nabla c\|^2}{2}

    Choosing η=FcT\eta = \frac{\|F\|}{\|\nabla c\|\sqrt{T}} minimizes the bound to: RL(T)FcTR_L(T) \le \|F\| \|\nabla c\| \sqrt{T}

  9. Knowl 9 — Z Fictitious Play

    algorithm

    The Z Fictitious Play algorithm is an application of Lazy Projection to repeated matrix games, providing a smooth alternative to standard fictitious play.

    Let A={1,,n}A = \{1, \dots, n\} be the player's action set, YY be the opponent's action set, and u:A×YRu : A \times Y \to \mathbb{R} be the utility function. At step tt, the algorithm maintains the cumulative historical payoff for each action and projects this vector onto the probability simplex Δ(A)={xRnxi0,i=1nxi=1}\Delta(A) = \{x \in \mathbb{R}^n \mid x_i \ge 0, \sum_{i=1}^n x_i = 1\}.

    Input: Action set A={1,,n}A = \{1, \dots, n\}, learning parameter η>0\eta > 0
    Output: Mixed strategy xtΔ(A)x^t \in \Delta(A) at each round tt
    for t=1,2,t = 1, 2, \dots do
        for each action iAi \in A do
            Compute yit=j=1t1ηu(i,hj,2)y^t_i = \sum_{j=1}^{t-1} \eta u(i, h_{j,2})
        end for
        Compute xt=argminxΔ(A)xyt2x^t = \arg\min_{x \in \Delta(A)} \|x - y^t\|_2
        Sample and play action according to distribution xtx^t
        Observe opponent action ht,2h_{t,2}
    end for
  10. Knowl 10 — Online Convex Programming via Online Linear Programming and Sampling

    model/method

    An online linear programming algorithm (OLPA) outputting distributions DtΔ(F)D^t \in \Delta(F) over a convex feasible set FF can be converted into an online convex programming (OCP) algorithm against convex cost functions ctc^t:

    1. Exact Conversion: At round tt, play the expected vector xt=EXDt[X]Fx^t = \mathbb{E}_{X \sim D^t}[X] \in F and pass the cost vector ct(xt)\nabla c^t(x^t) to the OLPA. Because the function is convex, EXDt[ct(X)]ct(xt)\mathbb{E}_{X \sim D^t}[c^t(X)] \ge c^t(x^t), guaranteeing that the linear cost linearization bounds the convex regret.
    2. Approximate Conversion (Sampling): When the expected vector xtx^t cannot be computed in closed form, sample sts_t points X1,,XstDtX_1, \dots, X_{s_t} \sim D^t independently, play the empirical mean zt=1sti=1stXiz^t = \frac{1}{s_t} \sum_{i=1}^{s_t} X_i, and feed ct(zt)\nabla c^t(z^t) to the OLPA.

    Setting the number of samples to st=ts_t = t per round yields an expected regret bound of: E[RApprox(T)]RExact(T)+cF(2T1)\mathbb{E}[R_{\text{Approx}}(T)] \le R_{\text{Exact}}(T) + \|\nabla c\| \|F\| (2\sqrt{T} - 1) where F=maxx,yFxy2\|F\| = \max_{x,y \in F} \|x - y\|_2 and c=supxF,t1ct(x)2\|\nabla c\| = \sup_{x \in F, t \ge 1} \|\nabla c^t(x)\|_2.

Coverage note — Algorithm 5 (the naive reduction from expert algorithms to online linear programs by assigning one expert per polytope vertex) and supporting geometric lemmas (Lemmas 4–7, Azuma's lemma, and Doob's decomposition) were omitted as they are standard background or proof apparatus for the main results.

References

  1. 1.S. Amari. Natural gradient works efficiently in learning. Neural Computation, 10:251–276, 1998.
  2. 2.N. Bansal, A. Blum, S. Chawla, and A. Meyerson. Online oblivious routing. Submitted, 2003.
  3. 3.D. Blackwell. An analog of the minimax theorem for vector payoffs. South Pacific J. of Mathematics, pages 1–8, 1956.
  4. 4.M. Bowling and M. Veloso. Convergence of gradient dynamics with a variable learning rate. In Proceedings of the Eighteenth International Conference on Machine Learning, pages 27–34, 2001.
  5. 5.N. Cesa-Bianchi, P. Long, and M. K. Warmuth. Worst-case quadratic bounds for on-line prediction of linear functions by gradient descent. IEEE Transactions on Neural Networks, 7:604–619, 1994.
  6. 6.S. Della Pietra, V. Della Pietra, and J. Lafferty. Duality and auxilary functions for Bregman distances. Technical Report CMU-CS-01-109, Carnegie Mellon University, 1999.
  7. 7.D. Foster. A proof of calibration via Blackwell's approachability theorem. In Games and Economic Behavior, volume 29, pages 73–79, 1999.
  8. 8.D. Foster and R. Vohra. Regret in the on-line decision problem. Games and Economic Behavior, 29(1):7–35, 1999.
  9. 9.Y. Freund and R. Schapire. Adaptive game playing using multiplicative weights. In Games and Economic Behavior, volume 29, pages 79–103, 1999.
  10. 10.D. Fudenberg and D. Levine. Universal consistency and cautious fictitious play. Journal of Economic Dynamics and Control, 19:1065–1089, 1995.
  11. 11.D. Fudenberg and D. Levine. The Theory of Learning in Games. MIT Press, 1998.
  12. 12.D. Fudenberg and D. Levine. Conditional universal consistency. Games and Economic Behavior, 29, 1999.
  13. 13.C. Gentile and M. Warmuth. Proving relative loss bounds for online learning algorithms by the Bregman divergence. In The 13th Annual Conference on Computational Learning Theory, June 2000. Tutorial.
  14. 14.J. Hannan. Approximation to bayes risk in repeated play. Annals of Mathematics Studies, 39:97–139, 1957.
  15. 15.S. Hart and A. Mas-Colell. A simple adaptive procedure leading to correlated equilibrium. Econometrica, 68:1127–1150, 2000.
  16. 16.S. Hart and A. Mas-Colell. A general class of adaptive strategies. Journal of Economic Theory, 98:26–54, 2001.
  17. 17.M. Herbster and M. K. Warmuth. Tracking the best linear predictor. Journal of Machine Learning Research, 1:281–309, 2001.
  18. 18.W. Hoeffding. Probability inequalities for sums of bounded random variables. Journal of the American Statistical Association, 58:13–30, March 1963.
  19. 19.A. Kalai and S. Vempala. Geometric algorithms for online optimization. Technical report, MIT, 2002.
  20. 20.J. Kivinen and M. Warmuth. Exponentiated gradient versus gradient descent for linear predictors. Information and Computation, 132:1–64, 1997.
  21. 21.J. Kivinen and M. Warmuth. Relative loss bounds for multidimensional regression problems. Machine Learning Journal, 45:301–329, 2001.
  22. 22.D. Levine. Personal communication, 2003.
  23. 23.N. Littlestone and M. K. Warmuth. The weighted majority algorithm. In Proceedings of the Second Annual Conference on Computational Learning Theory, 1989.
  24. 24.R. Mahony and R. Williamson. Prior knowledge and preferential structures in gradient descent algorithms. Journal of Machine Learning Research, 1:311–355, 2001.
  25. 25.S. Singh, M. Kearns, and Y. Mansour. Nash convergence of gradient dynamics in general-sum games. In Proceedings of the Sixteenth Conference in Uncertainty in Artificial Intelligence, pages 541–548, 2000.

Citation

MLA
Zinkevich, M. “Online Convex Programming and Generalized Infinitesimal Gradient Ascent”. International Conference on Machine Learning, 2003, pp. 928–35, http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.10.9960.
APA
Zinkevich, M. (2003). Online convex programming and generalized infinitesimal gradient ascent. International Conference on Machine Learning, 928–935. http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.10.9960
Chicago
Zinkevich, M. 2003. “Online Convex Programming and Generalized Infinitesimal Gradient Ascent”. International Conference on Machine Learning, 928–35. http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.10.9960.
Harvard
Zinkevich, M. (2003) “Online convex programming and generalized infinitesimal gradient ascent”, International Conference on Machine Learning, pp. 928–935. Available at: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.10.9960.
Vancouver
1. Zinkevich M (2003) Online convex programming and generalized infinitesimal gradient ascent. International Conference on Machine Learning 928–935

BibTeX

@article{zinkevich2003online,
  title = {Online convex programming and generalized infinitesimal gradient ascent},
  author = {Zinkevich, Martin},
  year = {2003},
  journal = {International Conference on Machine Learning},
  pages = {928-935},
  url = {http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.10.9960}
}
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