Date of Award


Degree Type


Degree Name

Master of Science


Epidemiology and Biostatistics


Dr. Guang Yong Zou


The intraclass correlation coefficient (ICC) has application in several fields of research. Various confidence interval methods for a single ICC are available. However, statis­ tical inference for multiple ICCs has primarily relied on hypothesis testing which cannot distinguish between statistical significance and practical importance. The focus of this thesis is to develop and evaluate confidence interval procedures for a difference between two correlated ICCs with variable class sizes. The strategy used in the thesis is to recover variance estimates needed for the confidence interval for the difference from the confidence limits for single ICCs. Simulation results show that the procedure based on inverse hyperbolic tangent transformation for single ICCs performs well. The Galton’s 1886 dataset on siblings heights is used to illustrate the methodology.



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