Study examines geometry of moduli space with bundle jumps and hypercomplex structures.
problem Investigates the geometry of Kodaira moduli space with bundle jumps.
method Identifies natural assumptions for extending Obata connection to logarithmic connection.
result Natural assumptions guarantee extension of Obata connection to logarithmic connection.
The paper studies horizontal semimartingales on Riemannian manifolds and their connections to Euclidean spaces.
problem Stochastic lifts and anti-developments of semimartingales on Riemannian manifolds.
method Using stochastic differential geometry with jumps, the paper establishes correspondences between discontinuous semimartingales and their lifts.
result The paper extends previous results to include geodesics and small jumps, enabling the construction of martingales from local martingales.
We study a smooth analogue of jumping curves of a holomorphic vector bundle, and use Yang-Mills theory over S2 to show that any non-trivial, smooth Hermitian vector bundle E over a smooth simply connected manifold, must have such curves. This is used to give new examples complex manifolds for which a non-tri…
Let X be a compact complex manifold and E be a holomorphic vector bundle on X. Given a deformation (X,E) of the pair (X,E) over a small polydisk B centered at the origin, we study the jumping phenomenon of the cohomology groups dimCHq(Xt,Et) near $t …
In this article we propose a model for stochastic delay differential equation with jumps (SDDEJ) in a differentiable manifold M endowed with a connection ∇. In our model, the continuous part is driven by vector fields with a fixed delay and the jumps are assumed to come from a distinct source of (càdlàg) noise…
For any integer k we construct an explicit example of a twistor space which contains a one--parameter family of jumping rational curves, where the normal bundle changes from O(1)+O(1) to O(k)+O(2−k). For k>3 the resulting anti--self--dual Ricci-flat manifold is a Zariski cone in the space of holomorphic section…
Unitons, i.e.\ harmonic spheres in a unitary group, correspond to \lq uniton bundles\rq, i.e.\ holomorphic bundles over the compactified tangent space to the complex line with certain triviality and other properties. In this paper, we use a monad representation similar to Donaldson's representation of instanton bundles…
Instanton bundles on P3 have been at the core of the research in Algebraic Geometry during the last thirty years. Motivated by the recent extension of their definition to other Fano threefolds of Picard number one, we develop the theory of instanton bundles on the complete flag variety F:=F(0,1,2) of poin…
Here we are fixing an output of a trivial calculation based on Konsevich's differential 2-form for the Chern class of polygon bundle. As a result an interesting combinatorics and arithmetics jumps right out of a jukebox. The calculation gives very simple rational combinatorial characteristics (we call it "curvature") o…
We describe the induced geometry on several classes of Kodaira moduli spaces of rational curves in twistor spaces. By constructing connections and frames on the moduli spaces we build and review twistor theories pertaining to relativistic and non-relativistic geometries. Focussing on the cases of three- and five-dimens…
We establish multiplicity results for geometrically distinct contractible closed Reeb orbits of non-degenerate contact forms on a broad class of prequantization bundles. The results hold under certain index requirements on the contact form and are sharp for unit cotangent bundles of CROSS's. In particular, we generaliz…
Starting from ideas of Furuta, we develop a general formalism for the construction of cohomotopy invariants associated with a certain class of S1-equivariant non-linear maps between Hilbert bundles. Applied to the Seiberg-Witten map, this formalism yields a new class of cohomotopy Seiberg-Witten invariants which hav…
The paper proves a conjecture for Kähler fibre spaces.
problem Proving the Iitaka conjecture for Kähler fibre spaces.
method Using positivity theorems and structure theorems on cohomology jumping loci.
result The klt Kähler version of the Iitaka conjecture holds true under certain conditions.
News might trigger jump arrivals in financial time series. The "bad" and "good" news seems to have distinct impact. In the research, a double exponential jump distribution is applied to model downward and upward jumps. Bayesian double exponential jump-diffusion model is proposed. Theorems stated in the paper enable est…
We quantify how co-jumps impact correlations in currency markets. To disentangle the continuous part of quadratic covariation from co-jumps, and study the influence of co-jumps on correlations, we propose a new wavelet-based estimator. The proposed estimation framework is able to localize the co-jumps very precisely th…
Neural jump model improves option pricing accuracy.
problem Jump risk in option pricing.
method Neural jump stochastic differential equation model with Gumbel-Softmax gradient learning.
result Neural jump components significantly improve option pricing accuracy.
Let X be a smooth complex projective variety of dimension d. It is classical that ample line bundles on X satisfy many beautiful geometric, cohomological, and numerical properties that render their behavior particularly tractable. By contrast, examples due to Cutkosky and others have led to the common impression that t…
Study reveals strong co-jumping behavior in U.S. yield curves compared to Europe.
problem Understanding co-jumps in interest rate futures markets.
method Localized co-jumps through wavelet coefficients, identified statistically significant ones, and analyzed using high frequency data.
result Stronger co-jumping behavior in U.S. yield curves compared to European ones.
Christmas causes 2-month LIBOR to jump.
problem Understanding the short-term pattern in LIBOR dynamics.
method Analyzed the 21 days before Xmas and the sign and size of the jump.
result 2-month LIBOR jumps after Christmas, influenced by the trend 21 days prior.
We investigate the extension of the multilevel Monte Carlo path simulation method to jump-diffusion SDEs. We consider models with finite rate activity, using a jump-adapted discretisation in which the jump times are computed and added to the standard uniform dis- cretisation times. The key component in multilevel analy…
Study proposes pricing mechanism for cryptocurrency options.
problem High speculation, volatility, and discontinuity in cryptocurrency markets.
method Proposes a pricing mechanism based on SVCJ model with co-jumps.
result Shows significant contemporaneous anti-correlation between jumps in price and volatility.
Develops a new model for pricing without arbitrage opportunities.
problem Arbitrage opportunities in standard jump-diffusion models.
method Introduces a multi-type jump-diffusion model with diffusion-dependent jumps.
result Derives no-arbitrage condition linking drift to model parameters.
Extends nonlinear filtering to predictable jump times.
problem Filtering with jumps in both signal and observation, especially when jump times are known.
method Derive Kushner-Stratonovich and Zakai equations for predictable discontinuities.
result Extends classical nonlinear filtering results to a setting with predictable discontinuities.
The paper studies the continuous-time dynamics of VIX with stochastic volatility and jumps in VIX and volatility. Built on the general parametric affine model with stochastic volatility and jump in logarithm of VIX, we derive a linear relation between the stochastic volatility factor and VVIX index. We detect the exist…
A method to identify new classes of price jumps in financial markets.
problem Separating endogenous and exogenous causes of price jumps.
method Wavelet-based representation of jump time-series.
result Identification of new classes of jumps and investigation of co-jumps.
Efficiently reconstructs jump-diffusion processes from data using neural networks.
problem Reconstructing jump-diffusion processes from data.
method Temporally decoupled squared Wasserstein distance method using parameterized neural networks.
result Enhanced reconstruction of jump-diffusion processes from data.
Optimal method detects jumps in jump-diffusion processes.
problem Detecting jumps in jump-diffusion processes with improved finite-sample performance.
method Iterative threshold-kernel method to optimally select threshold parameter.
result Approximate optimal threshold depends on spot volatility, jump intensity, and jump density.
The paper models financial data with multivariate jump processes.
problem Capturing the dynamics of financial data with jumps.
method Defined multivariate point processes driven by stochastic jumps, providing stability conditions.
result Nonlinear models fit financial data best, showing jumps cluster during crises.
Method detects jumps in high-frequency order prices using local minima.
problem Detecting jumps in high-frequency order prices with noisy data.
method Developed methods to estimate, locate and test for jumps using local minima of best ask quotes.
result Consistently estimated jump sizes and times, established asymptotic properties of tests, and demonstrated faster convergence rates.
Model predicts jump risk premia influencing cryptocurrency futures and option performance.
problem Capturing asymmetric and time-varying skewness in cryptocurrency returns.
method Bivariate Hawkes process with positive and negative jump premia.
result Inferred jump risk premia predict futures cost of carry and option performance.
The paper develops a deformation theory for Dolbeault cohomology classes.
problem Understanding the variations of Dolbeault cohomology classes.
method Established a deformation theory using the power series method and proved the extension equation.
result Proved the existence and unobstructedness of deformations under certain conditions.
Develops a fast and precise method to evaluate likelihood of jump-diffusion models.
problem Evaluating likelihood functions of models with stochastic volatility and jumps.
method Deterministic nonlinear filtering algorithm based on Kitagawa's method.
result Deterministic filtering is faster and more precise than particle filter.
A machine learning method for short-maturity options with jumps and stochastic volatility.
problem Short-maturity options with jumps and stochastic volatility.
method Differential machine learning method combining supervision and PIDE-residual penalty.
result Improves jump-term approximation and reduces Greeks errors compared to baselines.
RL for jump-diffusions applies to financial portfolio selection and option hedging.
problem Optimizing control in systems with jump-diffusion dynamics.
method Entropy-regularized exploratory control with stochastic policies, using existing diffusion algorithms with modifications.
result RL algorithms and parameterizations are invariant to jumps in jump-diffusion systems.
In order to understand the origin of stock price jumps, we cross-correlate high-frequency time series of stock returns with different news feeds. We find that neither idiosyncratic news nor market wide news can explain the frequency and amplitude of price jumps. We find that the volatility patterns around jumps and aro…
Investigates consistency of FX rate dynamics under inversion.
problem Consistency of jump-diffusion dynamics for FX rates under inversion.
method Calibrated Heston and SABR models, analyzed jumps in domestic and foreign measures.
result Determines conditions for consistency in FX rate dynamics under inversion.
Simplifies pricing options in jump-diffusion models using gauge transformations.
problem Pricing European options in affine jump-diffusion models.
method Gauge transformation in the dual space to reduce to diffusion model pricing.
result A general procedure for calculating Φ and applications in pricing and estimation. Study on stochastic volatility models with external shocks triggering jump cascades.
problem Analyzing the impact of external shocks on jump dynamics in stochastic volatility models.
method Establishing scaling limits for a class of stochastic volatility models with self-exciting jump dynamics.
result External shocks can trigger endogenous jump cascades in asset returns and volatility.
The paper introduces walks with jumps for modeling neuron activity in hyperbolic space.
problem Encoding neuron activity sequences in hyperbolic space.
method Introducing walks with jumps in hyperbolic geometry to model neuron activity.
result Endpoints of walks with jumps do not fully encode the sequence of jump times.
In quantitative finance, we often model asset prices as semimartingales, with drift, diffusion and jump components. The jump activity index measures the strength of the jumps at high frequencies, and is of interest both in model selection and fitting, and in volatility estimation. In this paper, we give a novel estimat…
Develops efficient methods for approximating densities of financial models with jumps.
problem Approximating densities of affine jump diffusions with state-independent jump intensities.
method Recursive approach for deriving closed-form solutions to moments, constructing density approximations via moment matching.
result Superior computational efficiency and precision in option pricing and simulation compared to existing techniques.
Bayesian model predicts stock jumps from daily returns data.
problem Disentangling volatility and jumps in daily stock returns.
method Bayesian framework for stochastic volatility with Poisson jumps, extended to large panels using dynamic factor models.
result Joint modelling of jumps improves predictive ability of stochastic volatility models.
Study on short-term behavior of ATM-IV for jump-diffusion model.
problem Analyzing the short-time behavior of ATM-IV for a specific stochastic volatility model.
method Used Malliavin Calculus techniques to derive expressions for ATM-IV level and skew.
result Short-time behavior of ATM-IV level is consistent for all pure-jump Lévy processes.
Study short maturity Asian options in jump-diffusion models with local volatility.
problem Analyzing Asian options pricing in models with jumps and local volatility.
method Asymptotic analysis for short maturity, considering fixed and floating strike options.
result Explicit results for Asian option prices in several models, including Merton, double-exponential, and Variance Gamma models.
The article uses jump-telegraph models to price zero coupon bonds and adjust convexity.
problem Pricing zero coupon bonds and adjusting for convexity in a short rate model.
method Markov-modulated model with jumps, jump-telegraph process, expectation hypothesis.
result Closed formulas for term structure and forward rates are derived.
Estimation of the covariance matrix of asset returns from high frequency data is complicated by asynchronous returns, market mi- crostructure noise and jumps. One technique for addressing both asynchronous returns and market microstructure is the Kalman-EM (KEM) algorithm. However the KEM approach assumes log-normal pr…
Investigates Bitcoin market risk, showing volatility and jumps impact future volatility.
problem Understanding and forecasting the risk dynamics of Bitcoin market.
method Comprehensive investigation using realized volatility and jumps analysis.
result Jumps, especially positive ones, reduce future realized variance; long-term realized variance benefits from modeling jumps.
Predicting stock jumps using liquidity and technical indicators.
problem Predicting intraday stock jumps in finance.
method Divide trading day into 5-minute intervals, use liquidity measures and technical indicators, apply machine learning algorithms.
result Initial evidence of predictability of jump arrivals and directions using level-2 stock data.