Suvimol Phanyaem. Explicit formulas of average run length for ARMA process. Doctoral Degree(Applied Statistics). มหาวิทยาลัยเทคโนโลยีพระจอมเกล้าพระนครเหนือ. สำนักหอสมุดกลาง. : มหาวิทยาลัยเทคโนโลยีพระจอมเกล้าพระนครเหนือ, 2013.
Explicit formulas of average run length for ARMA process
Abstract:
The objectives of this thesis are to derive explicit analytical formulas and develop
numerical integration for evaluating the Average Run Length (ARL) of Exponentially
Weighted Moving Average (EWMA) and Cumulative Sum (CUSUM) control charts
for the p order autoregressive and the q order moving average, ARMA(p,q) process
with exponential distribution white noise. The integral equations for solving the explicit
formulas for ARL and use the Gauss-Legendre quadrature rule to approximate the
numerical integration which both methods based on the Banachs Fixed Point theorem
which is used to guarantee the existence and uniqueness of the solution. The numerical
results obtained from the proposed explicit formulas are compared with results obtained
from numerical integration technique. The comparison of the performance of the EWMA
and CUSUM control charts are studied and presented. The results show that the ARL
from explicit formulas is close to the numerical integration with an absolute percentage
difference less than 1%. In addition, the explicit formulas can reduce in the computational
time better than the numerical integration.