Subject Area
Statistics
Abstract
In this dissertation, improved statistical methods for time-series and lifetime data are developed. First, an improved trend test for time series data is presented. Then, robust parametric estimation methods based on system lifetime data with known system signatures are developed.
In the first part of this dissertation, we consider a test for the monotonic trend in time series data proposed by Brillinger (1989). It has been shown that when there are highly correlated residuals or short record lengths, Brillinger’s test procedure tends to have significance level much higher than the nominal level. This could be related to the discrepancy between the empirical distribution of the test statistic and the asymptotic normal distribution. Hence, different bootstrap-based procedures are proposed based on the Brillinger test statistic. The performances of proposed bootstrap test procedures are evaluated through an extensive Monte Carlo simulation study, and are compared to other trend test procedures in the literature.
In the second part of this dissertation, we consider the estimation of component reliability based on system lifetime data with known system signature using the minimum density divergence estimation method. Different estimation procedures based on the minimum density divergence estimation method are proposed. We also study the standard error estimation and interval estimation procedures for the proposed minimum density divergence estimator. Based on the proposed procedures, a Monte Carlo simulation study is used to evaluate the performance of these proposed procedures and compare these procedures with the maximum likelihood estimation under different contaminated mod- els. Then, a numerical example is presented to illustrate the minimum density divergence estimation method. In particular, we show that the proposed estimation procedures are robust to contamination and model misspecification.
Degree Date
Fall 12-19-2020
Document Type
Dissertation
Degree Name
Ph.D.
Department
Statistical Science
Advisor
Hon Keung Tony Ng
Number of Pages
104
Format
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License
Recommended Citation
Zhu, Xiaojie, "Improved Statistical Methods for Time-series and Lifetime Data" (2020). Statistical Science Theses and Dissertations. 19.
https://scholar.smu.edu/hum_sci_statisticalscience_etds/19
Included in
Applied Statistics Commons, Longitudinal Data Analysis and Time Series Commons, Statistical Methodology Commons, Survival Analysis Commons
