Abstract:
Multilevel data structure generally consists of multiple units of analysis, one nested within the
other. This type of data structure can be discovered in a natural way or as designed experiments.
Many types of data that are available in the fields of Education and Medicine have a multilevel
data structure. The modelling of multilevel data on various aspects has been developed for
several years. However, the area of multilevel modelling for ordinal categorical response is a
novel application. The study mainly aimed at finding out whether the time period together with
the other factors (i.e. Grade, Gender, Race and School Size) have a significant effect on the
General Certificate of Education Ordinary Level (G.C.E. O/L) pass rate of schools in Northern
and Eastern Provinces of Sri Lanka While observing the hierarchical structure of the data into
Schools and Districts levels, and determining how these levels impact with the G.C.E. O/L pass
rates. In this study, the time period has been taken from 2005 to 2014 while it is categorized as
war period (from 2005 to 2009) and post-war period (from 2010 to 2014). The application of
advanced analysis in this study focused on modelling a two level Generalized Multilevel
Ordinal Model using the Bayesian Markov Chain Monte Carlo (MCMC) estimation method
from MLwiN 2.10 software. The response variable was the G.C.E. O/L pass rates of Schools.
Here, the number of students at first attempt have been considered for the G.C.E. O/L pass rate
while explanatory variables were Grade, Gender, Time Period, Race and School Size. 8,455
schools were selected for the sample. In Advanced Analysis of this study, Generalized
Multilevel Ordinal Model was developed under two approaches. One approach was to develop
a proportional odds model and the second approach was to develop a partial non-proportional
odds model. Ultimately, the partial non-proportional odds model based on the DIC diagnostic
was selected as the most appropriate model for the data. In the final model, the variable time
period provided a significant main effect. It has been proved that the odds ratio of a school
having a less than or equal pass rate opposed to a greater pass rate during the post-war period
is lower than during the war period in Northern and Eastern provinces of Sri Lanka.
