dc.contributor.advisor |
Wild, C |
en |
dc.contributor.author |
Grimson, Fiona |
en |
dc.date.accessioned |
2011-02-01T01:04:12Z |
en |
dc.date.issued |
2011 |
en |
dc.identifier.uri |
http://hdl.handle.net/2292/6145 |
en |
dc.description |
Full text is available to authenticated members of The University of Auckland only. |
en |
dc.description.abstract |
We consider the analysis of two-phase samples where a large cohort is sampled at the first phase with a smaller subsample taken at the second phase. Some variables are observed at the first phase for the whole cohort and some at the second phase only for the subsample. Methods of utilising the partial observations to improve estimation of regression coefficients are investigated. We investigate methods that involve the use of partial information to estimate auxiliary variables, rather than impute missing data values. We focus on the comparison of three methods which are all of the calibration class of estimators and are asymptotically equivalent. We wish to assess their performance and potential to increase efficiency over standard analysis techniques infinite samples. This is done through simulation studies comparing the performances of these methods in a variety of settings, including both binary and continuous response variables, stratified data and the availability of surrogate information. A substantial finite sample effect was observed. The partial data methods were found to perform well, particularly the iterated methods. An advantage was also found using direct estimation of the optimal auxiliary variables. We also consider methods of estimating the variance of parameter estimates generated by these methods from a single data set. Variance estimation methods are also tested through simulation studies. |
en |
dc.publisher |
ResearchSpace@Auckland |
en |
dc.relation.ispartof |
Masters Thesis - University of Auckland |
en |
dc.relation.isreferencedby |
UoA99216072814002091 |
en |
dc.rights |
Restricted Item. Available to authenticated members of The University of Auckland. |
en |
dc.rights.uri |
https://researchspace.auckland.ac.nz/docs/uoa-docs/rights.htm |
en |
dc.title |
Methods for Utilising Partially Missing Data in Two-Phase Sampling |
en |
dc.type |
Thesis |
en |
thesis.degree.discipline |
Statistics |
en |
thesis.degree.grantor |
The University of Auckland |
en |
thesis.degree.level |
Masters |
en |
dc.rights.holder |
Copyright: The author |
en |
pubs.elements-id |
202308 |
en |
pubs.record-created-at-source-date |
2011-02-01 |
en |
dc.identifier.wikidata |
Q112886379 |
|