@article{mcsorley_lu_li_2002, title={Performance of parameter-estimates in step-stress accelerated life-tests with various sample-sizes}, volume={51}, DOI={10.1109/TR.2002.80288}, number={3}, journal={IEEE Transactions on Reliability}, author={McSorley, E. O. and Lu, J. C. and Li, C. S.}, year={2002}, pages={271–277} }
 @article{chen_li_lu_park_2000, title={Parameter estimation for bivariate shock models with singular distribution for censored data with concomitant order statistics}, volume={42}, ISSN={["1369-1473"]}, DOI={10.1111/1467-842X.00129}, abstractNote={When two‐component parallel systems are tested, the data consist of Type‐II censored data X(i), i= 1, n, from one component, and their concomitants     Y [i] randomly censored at X(r), the stopping time of the experiment. Marshall & Olkin's (1967) bivariate exponential distribution is used to illustrate statistical inference procedures developed for this data type. Although this data type is motivated practically, the likelihood is complicated, and maximum likelihood estimation is difficult, especially in the case where the parameter space is a non‐open set. An iterative algorithm is proposed for finding maximum likelihood estimates. This article derives several properties of the maximum likelihood estimator (MLE) including existence, uniqueness, strong consistency and asymptotic distribution. It also develops an alternative estimation method with closed‐form expressions based on marginal distributions, and derives its asymptotic properties. Compared with variances of the MLEs in the finite and large sample situations, the alternative estimator performs very well, especially when the correlation between X and Y is small.}, number={3}, journal={AUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS}, author={Chen, D and Li, CS and Lu, JC and Park, J}, year={2000}, month={Sep}, pages={323–336} }
 @article{li_lu_park_1999, title={Multivariate zero-inflated Poisson models and their applications}, volume={41}, ISSN={["0040-1706"]}, DOI={10.2307/1270992}, abstractNote={The zero-inflated Poisson (ZIP) distribution has been shown to be useful for modeling outcomes of manufacturing processes producing numerous defect-free products. When there are several types of defects, the multivariate ZIP (MZIP) model can be useful to detect specific process equipment problems and to reduce multiple types of defects simultaneously. This article proposes types of MZIP models and investigates distributional properties of an MZIP model. Finite-sample simulation studies show that, compared to the method of moments, the maximum likelihood method has smaller bias and variance, as well as more accurate coverage probability in estimating model parameters and zero-defect probability. Real-life examples from a major electronic equipment manufacturer illustrate how the proposed procedures are useful in a manufacturing environment for equipment-fault detection and for covariate effect studies.}, number={1}, journal={TECHNOMETRICS}, author={Li, CS and Lu, JC and Park, JH}, year={1999}, month={Feb}, pages={29–38} }
 @article{chen_lu_hughes-oliver_li_1998, title={Asymptotic properties of maximum likelihood estimates for a bivariate exponential distribution and mixed censored data}, volume={48}, ISSN={["0026-1335"]}, DOI={10.1007/s001840050003}, number={2}, journal={METRIKA}, author={Chen, D and Lu, JC and Hughes-Oliver, JM and Li, CS}, year={1998}, pages={109–125} }