The Slovenian Public Opinion survey (SPOS), which carried out in 1990, was used by the government of Slovenia as a benchmark to prepare for an upcoming plebiscite, which asked the respondents whether they support independence from Yugoslavia. However, the sample size was large and it is quite likely that the respondents and nonrespondents had divergent viewpoints. We first develop an ignorable nonresponse model which is an extension of a bivariate binomial model. In order to accommodate the nonrespondents, we then develop a nonignorable nonresponse model which is an extension of the ignorable model. Our methodology uses an EM algorithm to fit both the ignorable and nonignorable nonresponse models, and estimation is carried out using the bootstrap mechanism. We also perform sensitivity analysis to study different degrees of departures of the nonignorable nonresponse model from the ignorable nonresponse model. We found that the nonignorable nonresponse model is mildly sensitive to departures from the ignorable nonresponse model. In fact, our finding based on the nonignorable model is better than an earlier conclusion about another nonignorable nonresponse model fitted to these data.

Creator

• Zong, Yujie

Contributors

• Bhadra, Dhiman
• Nandram, Balgobin

Degree

• MS

Unit

• Mathematical Sciences

Publisher

• Worcester Polytechnic Institute

Language

• English

Identifier

• etd-041511-155723

Keyword

• Bootstrap
• 2X2 categorical tables
• EM algorithm
• Multinomial model
• Bivariate binomial distribution
• Missing not at random

Advisor

• Bhadra, Dhiman
• Nandram, Balgobin

Defense date

• 2011-03-28

Year

• 2011

Date created

• 2011-04-15

Resource type

• Thesis

Rights statement

• In Copyright