Results 41 to 50 of about 36,708 (189)

Miners' Reward Elasticity and Stability of Competing Proof‐of‐Work Cryptocurrencies

International Economic Review, EarlyView.
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, Junpei Komiyama, Shunya Noda   +2 more
wiley   +1 more source

On Metric Choice in Dimension Reduction for Fréchet Regression

International Statistical Review, EarlyView.
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, Congli Ma, Siyu Chen, Obed Koomson   +3 more
wiley   +1 more source

Piecewise Constant Martingales and Lazy Clocks

, 2017
This paper discusses the possibility to find and construct \textit{piecewise constant martingales}, that is, martingales with piecewise constant sample paths evolving in a connected subset of $\mathbb{R}$.
Profeta, Christophe, Vrins, Frédéric
core   +1 more source

A Comparative Review of Specification Tests for Diffusion Models

International Statistical Review, EarlyView.
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, D. Diz‐Castro, M. Febrero‐Bande, W. González‐Manteiga   +3 more
wiley   +1 more source

Model Ambiguity versus Model Misspecification in Dynamic Portfolio Choice

The Journal of Finance, EarlyView.
ABSTRACT We study aversion to model ambiguity and misspecification in dynamic portfolio choice. Risk‐averse investors (relative risk aversion γ>1$\gamma > 1$) fear return persistence, while risk‐tolerant investors (0<γ<1$0<\gamma <1$) fear mean reversion, when confronting model misspecification concerns of identically and independently distributed (IID)
PASCAL J. MAENHOUT, HAO XING, ANNE G. BALTER   +2 more
wiley   +1 more source

Learning in the Limit: Income Inference from Credit Extensions

The Journal of Finance, EarlyView.
ABSTRACT Combining a randomized controlled trial with administrative and survey data, this paper shows that credit limit extensions significantly increase total spending and income expectations. By controlling for changes in personal income expectations, the spending response to credit limit extensions weakens by approximately 30%.
XIAO YIN
wiley   +1 more source

Time‐Varying Dispersion Integer‐Valued GARCH Models

Journal of Time Series Analysis, EarlyView.
ABSTRACT We introduce a general class of INteger‐valued Generalized AutoRegressive Conditionally Heteroscedastic (INGARCH) processes by allowing simultaneously time‐varying mean and dispersion parameters. We call such models time‐varying dispersion INGARCH (tv‐DINGARCH) models.
Wagner Barreto‐Souza, Luiza S. C. Piancastelli, Konstantinos Fokianos, Hernando Ombao   +3 more
wiley   +1 more source

Predicting Win-Loss Probabilities for Composite Time-to-Event Outcomes Under The Proportional Win-Fractions Regression Model. [PDF]

Stat Med
ABSTRACT For composite time‐to‐event outcomes, the win ratio as a relative measure ignores ties resulting from non‐occurrence of events, which can obscure important context in regression settings where event rates—and hence the proportion of ties—vary over time and across covariate values.
Mao L.
europepmc   +2 more sources

Functional Vašiček Model

Journal of Time Series Analysis, EarlyView.
ABSTRACT We propose a new formulation of the Vašičekmodel within the framework of functional data analysis. We treat observations (continuous‐time rates) within a suitably defined trading day as a single statistical object. We then consider a sequence of such objects, indexed by day.
Piotr Kokoszka, Neda Mohammadi, Leonardo Santoro, Hong Miao, Haonan Wang   +4 more
wiley   +1 more source

On Changing Time for Two-Parameter Strong Martingales: A Counterexample

The Annals of Probability, 1986
Brownian motion owes part of its significance to the fact that any continuous martingale may be considered as a Brownian motion running with a different clock. This means that by a suitable time change any continuous martingale can be transformed into Brownian motion.
openaire   +3 more sources