activity
20092023
most citedEfficient Computer Network Anomaly Detection by Changepoint Detection Methods

155 citations · 486 across the 22 of their papers we have counts for

collaborators

27 papers

math.ST2023

More On the Quasi-Stationary Distribution of the Shiryaev--Roberts Diffusion

Soumik Banerjee, Aleksey S. Polunchenko

We consider the classical Shiryaev--Roberts martingale diffusion, , restricted to the interval , where is a preset absorbing boundary. We take yet anoth…

stat.CO2019

On the Convergence Rate of the Quasi- to Stationary Distribution for the Shiryaev-Roberts Diffusion

Kexuan Li, Aleksey S. Polunchenko

For the classical Shiryaev--Roberts martingale diffusion considered on the interval , where is a given absorbing boundary, it is shown that the rate of convergence of…

stat.CO2019

Analytic Evaluation of the Fractional Moments for the Quasi-Stationary Distribution of the Shiryaev Martingale on an Interval

Kexuan Li, Aleksey S. Polunchenko, Andrey Pepelyshev

We consider the quasi-stationary distribution of the classical Shiryaev diffusion restricted to the interval with absorption at a fixed . We derive analytically a clos…

stat.ME2018

Analytic moment and Laplace transform formulae for the quasi-stationary distribution of the Shiryaev diffusion on an interval

Aleksey S. Polunchenko, Andrey Pepelyshev

We derive analytic closed-form moment and Laplace transform formulae for the quasi-stationary distribution of the classical Shiryaev diffusion restricted to the interval wi…

math.PR2017

A Note on the Quasi-Stationary Distribution of the Shiryaev Martingale on the Positive Half-Line

Aleksey S. Polunchenko, Servet Martinez, Jaime San Martin

We obtain a closed-form formula for the quasi-stationary distribution of the classical Shiryaev martingale diffusion considered on the positive half-line with f…

stat.CO2017

Comparative Performance Analysis of the Cumulative Sum Chart and the Shiryaev-Roberts Procedure for Detecting Changes in Autocorrelated Data

Aleksey S. Polunchenko, Vasanthan Raghavan

We consider the problem of quickest change-point detection where the observations form a first-order autoregressive (AR) process driven by temporally independent standard Gaussian…

stat.ME2017

Asymptotic Exponentiality of the First Exit Time of the Shiryaev-Roberts Diffusion with Constant Positive Drift

Aleksey S. Polunchenko

We consider the first exit time of a Shiryaev-Roberts diffusion with constant positive drift from the interval where . We show that the moment generating function (Lap…

stat.AP2016

Optimal Design of the Shiryaev-Roberts Chart: Give Your Shiryaev-Roberts a Headstart

Aleksey S. Polunchenko

We offer a numerical study of the effect of headstarting on the performance of a Shiryaev-Roberts (SR) chart set up to control the mean of a normal process. The study is a natural…

math.ST2016

Asymptotic Near-Minimaxity of the Randomized Shiryaev-Roberts-Pollak Change-Point Detection Procedure in Continuous Time

Aleksey S. Polunchenko

For the classical continuous-time quickest change-point detection problem it is shown that the randomized Shiryaev-Roberts-Pollak procedure is asymptotically nearly minimax-optimal…

math.ST2016★ 11 cited

On the Quasi-Stationary Distribution of the Shiryaev-Roberts Diffusion

Aleksey S. Polunchenko

We consider the diffusion generated by the equation with fixed, and where is given, and i…

stat.ME2016

A Note on Efficient Performance Evaluation of the Cumulative Sum Chart and the Sequential Probability Ratio Test

Aleksey S. Polunchenko

We establish a simple connection between certain in-control characteristics of the CUSUM Run Length and their out-of-control counterparts. The connection is in the form of paired i…

stat.ME2016★ 11 cited

An Analytic Expression for the Distribution of the Generalized Shiryaev-Roberts Diffusion

Aleksey S. Polunchenko, Grigory Sokolov

We consider the quickest change-point detection problem where the aim is to detect the onset of a pre-specified drift in "live"-monitored standard Brownian motion; the change-point…

math.ST2016★ 10 cited

Exact Distribution of the Generalized Shiryaev-Roberts Stopping Time Under the Minimax Brownian Motion Setup

Aleksey S. Polunchenko

We consider the quickest change-point detection problem where the aim is to detect the onset of a pre-specified drift in "live"-monitored standard Brownian motion; the change-point…

stat.AP2015

Real-time financial surveillance via quickest change-point detection methods

Andrey Pepelyshev, Aleksey S. Polunchenko

We consider the problem of efficient financial surveillance aimed at "on-the-go" detection of structural breaks (anomalies) in "live"-monitored financial time series. With the prob…

stat.CO2015

On Robustness of the Shiryaev-Roberts Procedure for Quickest Change-Point Detection under Parameter Misspecification in the Post-Change Distribution

Wenyu Du, Aleksey S. Polunchenko, Grigory Sokolov

The gist of the quickest change-point detection problem is to detect the presence of a change in the statistical behavior of a series of sequentially made observations, and do so i…

stat.ME2014

An Exact Formula for the Average Run Length to False Alarm of the Generalized Shiryaev-Roberts Procedure for Change-Point Detection under Exponential Observations

Wenyu Du, Grigory Sokolov, Aleksey S. Polunchenko

We derive analytically an exact closed-form formula for the standard minimax Average Run Length (ARL) to false alarm delivered by the Generalized Shiryaev-Roberts (GSR) change-poin…

stat.CO2013

Efficient Performance Evaluation of the Generalized Shiryaev--Roberts Detection Procedure in a Multi-Cyclic Setup

Aleksey S. Polunchenko, Grigory Sokolov, Wenyu Du

We propose a numerical method to evaluate the performance of the emerging Generalized Shiryaev--Roberts (GSR) change-point detection procedure in a "minimax-ish" multi-cyclic setup…

math.ST2013★ 18 cited

Quickest Change-Point Detection: A Bird's Eye View

Aleksey S. Polunchenko, Grigory Sokolov, Wenyu Du

We provide a bird's eye view onto the area of sequential change-point detection. We focus on the discrete-time case with known pre- and post-change data distributions and offer a s…

stat.AP2013

Optimal Design and Analysis of the Exponentially Weighted Moving Average Chart for Exponential Data

Aleksey S. Polunchenko, Grigory Sokolov, Alexander G. Tartakovsky

We study optimal design of the Exponentially Weighted Moving Average (EWMA) chart by a proper choice of the smoothing factor and the initial value (headstart) of the decision stati…

stat.CO2013

An Accurate Method for Determining the Pre-Change Run-Length Distribution of the Generalized Shiryaev--Roberts Detection Procedure

Aleksey S. Polunchenko, Grigory Sokolov, Wenyu Du

Change-of-measure is a powerful technique used across statistics, probability and analysis. Particularly known as Wald's likelihood ratio identity, the technique enabled the proof…

stat.AP2012★ 155 cited

Efficient Computer Network Anomaly Detection by Changepoint Detection Methods

Alexander G. Tartakovsky, Aleksey S. Polunchenko, Grigory Sokolov

We consider the problem of efficient on-line anomaly detection in computer network traffic. The problem is approached statistically, as that of sequential (quickest) changepoint de…

math.ST2012★ 15 cited

Nearly Optimal Change-Point Detection with an Application to Cybersecurity

Aleksey S. Polunchenko, Alexander G. Tartakovsky, Nitis Mukhopadhyay

We address the sequential change-point detection problem for the Gaussian model where baseline distribution is Gaussian with variance σ^2 and mean μsuch that σ^2=aμ, where a>0 is a…

math.ST2011★ 127 cited

State-of-the-Art in Sequential Change-Point Detection

Aleksey S. Polunchenko, Alexander G. Tartakovsky

We provide an overview of the state-of-the-art in the area of sequential change-point detection assuming discrete time and known pre- and post-change distributions. The overview sp…

math.ST2010

Third-order Asymptotic Optimality of the Generalized Shiryaev-Roberts Changepoint Detection Procedures

Alexander G. Tartakovsky, Moshe Pollak, Aleksey S. Polunchenko

Several variations of the Shiryaev-Roberts detection procedure in the context of the simple changepoint problem are considered: starting the procedure at (the original Shir…