Results 61 to 70 of about 2,001,462 (190)
ABSTRACT We study a random recursive tree model featuring complete redirection called the random friend tree and introduced by Saramäki and Kaski (2004). Vertices are attached sequentially, one by one, by selecting an existing target vertex and connecting to one of its neighbours (or friends), chosen uniformly at random.
Louigi Addario‐Berry +5 more
wiley +1 more source
Miners' Reward Elasticity and Stability of Competing Proof‐of‐Work Cryptocurrencies
ABSTRACT Proof‐of‐Work cryptocurrencies employ miners to sustain the system through algorithmic reward adjustments. We develop a stochastic model of the multicurrency mining and identify conditions for stable transaction speeds. Bitcoin's algorithm requires hash supply elasticity <$<$1 for stability, while ASERT remains stable for any elasticity and ...
Kohei Kawaguchi +2 more
wiley +1 more source
Local Time for Two-Parameter Continuous Martingales with Respect to the Quadratic Variation
The author studies the local time for two-parameter continuous martingales M as a density of the ``measure of sojourn time'' with respect to the quadratic variation \(\). First she shows that there exists a process \(\{L(x,s,t);\) \(x\in {\mathbb{R}}\setminus \{0\},\) \((s,t)\in {\mathbb{R}}^ 2_+\}\) satisfying the occupation density formula and which ...
openaire +3 more sources
On Metric Choice in Dimension Reduction for Fréchet Regression
Summary Fréchet regression is becoming a mainstay in modern data analysis for analysing non‐traditional data types belonging to general metric spaces. This novel regression method is especially useful in the analysis of complex health data such as continuous monitoring and imaging data.
Abdul‐Nasah Soale +3 more
wiley +1 more source
A Comparative Review of Specification Tests for Diffusion Models
Summary Diffusion models play an essential role in modelling continuous‐time stochastic processes in the financial field. Therefore, several proposals have been developed in the last decades to test the specification of stochastic differential equations.
A. López‐Pérez +3 more
wiley +1 more source
Inference on the Attractor Space via Functional Approximation
ABSTRACT This paper discusses semiparametric inference on hypotheses on the cointegration and the attractor spaces for I(1) linear processes with moderately large cross‐sectional dimension. The approach is based on sample canonical correlations and functional approximation of Brownian motions, and it can be applied both to the whole system and or to ...
Massimo Franchi, Paolo Paruolo
wiley +1 more source
Confidence Intervals for Price Discovery
ABSTRACT This paper discusses asymptotic and bootstrap confidence intervals for multivariate permanent‐transitory decompositions of cointegrated vector autoregressive I(1) systems, with a focus on price discovery. Alternative estimators of the permanent components are compared in terms of efficiency also under separable linear restrictions on the ...
Heino Bohn Nielsen +2 more
wiley +1 more source
Least Trimmed Squares: Cointegration and Outliers
ABSTRACT When applying the cointegrated autoregressive distributed lag model it is common to include indicator variables for outliers. This is often done in a somewhat ad hoc way. Least Trimmed Squares estimation provides a more systematic approach. This estimator is robust to a large number of outliers of many types.
Vanessa Berenguer‐Rico, Bent Nielsen
wiley +1 more source
Inference on Common Trends in a Cointegrated Nonlinear SVAR
ABSTRACT We consider the problem of performing inference on the number of common stochastic trends when data is generated by a cointegrated CKSVAR (a two‐regime, piecewise affine SVAR; Mavroeidis, 2021), using a modified version of the Breitung (2002) multivariate variance ratio test that is robust to the presence of nonlinear cointegration (of a known
James A. Duffy, Xiyu Jiao
wiley +1 more source
A sequential quadratic Hamiltonian‐based estimation method for Box‐Cox transformation cure model
ABSTRACT We propose an enhanced estimation method for the Box‐Cox transformation (BCT) cure rate model parameters by introducing a generic maximum likelihood estimation algorithm, the sequential quadratic Hamiltonian (SQH) scheme, which is based on a gradient‐free approach.
Phuong Bui +3 more
wiley +1 more source

