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KPZ formula for log-infinitely divisible multifractal random measures

Rémi Rhodes, Vincent Vargas (2012)

ESAIM: Probability and Statistics

We consider the continuous model of log-infinitely divisible multifractal random measures (MRM) introduced in [E. Bacry et al. Comm. Math. Phys.236 (2003) 449–475]. If M is a non degenerate multifractal measure with associated metric ρ(x,y) = M([x,y]) and structure function ζ, we show that we have the following relation between the (Euclidian) Hausdorff dimension dimH of a measurable set K and the Hausdorff dimension dimHρ with respect to ρ of the same set: ζ(dimHρ(K)) = dimH(K). Our results can...

Large deviations for independent random variables – Application to Erdös-Renyi’s functional law of large numbers

Jamal Najim (2005)

ESAIM: Probability and Statistics

A Large Deviation Principle (LDP) is proved for the family 1 n 1 n 𝐟 ( x i n ) · Z i n where the deterministic probability measure 1 n 1 n δ x i n converges weakly to a probability measure R and ( Z i n ) i are d -valued independent random variables whose distribution depends on x i n and satisfies the following exponential moments condition: sup i , n 𝔼 e α * | Z i n | < + forsome 0 < α * < + . In this context, the identification of the rate function is non-trivial due to the absence of equidistribution. We rely on fine convex analysis to address this issue. Among the applications of this result, we extend...

Large deviations for independent random variables – Application to Erdös-Renyi's functional law of large numbers

Jamal Najim (2010)

ESAIM: Probability and Statistics

A Large Deviation Principle (LDP) is proved for the family 1 n 1 n 𝐟 ( x i n ) · Z i n where the deterministic probability measure 1 n 1 n δ x i n converges weakly to a probability measure R and ( Z i n ) i are d -valued independent random variables whose distribution depends on x i n and satisfies the following exponential moments condition: sup i , n 𝔼 e α * | Z i n | < + forsome 0 < α * < + . In this context, the identification of the rate function is non-trivial due to the absence of equidistribution. We rely on fine convex analysis to address this issue. Among the applications of this result,...

Large scale behaviour of the spatial 𝛬 -Fleming–Viot process

N. Berestycki, A. M. Etheridge, A. Véber (2013)

Annales de l'I.H.P. Probabilités et statistiques

We consider the spatial 𝛬 -Fleming–Viot process model (Electron. J. Probab.15(2010) 162–216) for frequencies of genetic types in a population living in d , in the special case in which there are just two types of individuals, labelled 0 and 1 . At time zero, everyone in a given half-space has type 1, whereas everyone in the complementary half-space has type 0 . We are concerned with patterns of frequencies of the two types at large space and time scales. We consider two cases, one in which the dynamics...

Lévy processes conditioned on having a large height process

Mathieu Richard (2013)

Annales de l'I.H.P. Probabilités et statistiques

In the present work, we consider spectrally positive Lévy processes ( X t , t 0 ) not drifting to + and we are interested in conditioning these processes to reach arbitrarily large heights (in the sense of the height process associated with X ) before hitting 0 . This way we obtain a new conditioning of Lévy processes to stay positive. The (honest) law x of this conditioned process (starting at x g t ; 0 ) is defined as a Doob h -transform via a martingale. For Lévy processes with infinite variation paths, this martingale...

Limit theorems for measure-valued processes of the level-exceedance type

Andriy Yurachkivsky (2012)

ESAIM: Probability and Statistics

Let, for each t∈T, ψ(t, ۔) be a random measure on the Borel σ-algebra in ℝd such that Eψ(t, ℝd)k < ∞ for all k and let ψ ^ (t, ۔) be its characteristic function. We call the function ψ ^ (t1,…, tl ; z1,…, zl) = 𝖤 j = 1 l ψ ^ ( t j , z j ) of arguments l∈ ℕ, t1, t2… ∈T, z1, z2∈ ℝd the covaristic of the measure-valued random function (MVRF) ψ(۔, ۔). A general limit theorem for MVRF's in terms of covaristics is proved and applied to functions of the kind ψn(t, B) = µ{x : ξn(t, x) ∈B}, where μ is a nonrandom finite measure...

Limit theorems for measure-valued processes of the level-exceedance type

Andriy Yurachkivsky (2011)

ESAIM: Probability and Statistics

Let, for each t ∈ T, ψ(t, ۔) be a random measure on the Borel σ-algebra in ℝd such that Eψ(t, ℝd)k &lt; ∞ for all kand let ψ ^ (t, ۔) be its characteristic function. We call the function ψ ^ (t1,…, tl ; z1,…, zl) = 𝖤 j = 1 l ψ ^ ( t j , z j ) of argumentsl ∈ ℕ, t1, t2… ∈ T, z1, z2 ∈ ℝd the covaristic of the measure-valued random function (MVRF) ψ(۔, ۔). A general limit theorem for MVRF's in terms of covaristics is proved and applied to functions of the kind ψn(t, B) = µ{x : ξn(t, x) ∈ B}, where μ is a nonrandom finite measure...

Limiting distribution for a simple model of order book dynamics

Łukasz Kruk (2012)

Open Mathematics

A continuous-time model for the limit order book dynamics is considered. The set of outstanding limit orders is modeled as a pair of random counting measures and the limiting distribution of this pair of measure-valued processes is obtained under suitable conditions on the model parameters. The limiting behavior of the bid-ask spread and the midpoint of the bid-ask interval are also characterized.

Limiting spectral distribution of XX' matrices

Arup Bose, Sreela Gangopadhyay, Arnab Sen (2010)

Annales de l'I.H.P. Probabilités et statistiques

The methods to establish the limiting spectral distribution (LSD) of large dimensional random matrices includes the well-known moment method which invokes the trace formula. Its success has been demonstrated in several types of matrices such as the Wigner matrix and the sample covariance matrix. In a recent article Bryc, Dembo and Jiang [Ann. Probab.34 (2006) 1–38] establish the LSD for random Toeplitz and Hankel matrices using the moment method. They perform the necessary counting of terms in the...

Mean quadratic convergence of signed random measures

Pierre Jacob, Paulo Eduardo Oliveira (1991)

Commentationes Mathematicae Universitatis Carolinae

We consider signed Radon random measures on a separable, complete and locally compact metric space and study mean quadratic convergence with respect to vague topology on the space of measures. We prove sufficient conditions in order to obtain mean quadratic convergence. These results are based on some identification properties of signed Radon measures on the product space, also proved in this paper.

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