Browsing Statistics by Issue Date
Now showing items 21-40 of 119
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Modeling the factors affecting cereal crop yields in the Amhara National Regional State of Ethiopia.
(2010)The agriculture sector in Amhara National Regional State is characterised by producing cereal crops which occupy the largest percentage (84.3%) of the total crop area cultivated in the region. As a result, it is imperative ... -
Modelling longitudinal counts data with application to recurrent epileptic seizure events.
(2010)The objectives of this thesis is to explore different approaches of modelling clustered correlated data in the form of repeated or longitudinal counts data leading to a replicated Poisson process. The specific application ... -
Application of statistical multivariate techniques to wood quality data.
(2010)Sappi is one of the leading producer and supplier of Eucalyptus pulp to the world market. It is also a great contributor to South Africa economy in terms of employment opportunity to the rural people through its large ... -
Longitudinal analysis of the effect of climatic factors on the wood anatomy of two eucalypt clones
(2010)Eucalypt trees are one of tree species used for the manufacturing of papers in South Africa. The manufacturing of paper consists of cooking the wood with chemicals until obtaining a pulp. The wood is made of different ... -
Longitudinal analysis of the effect of climatic factors on the wood anatomy of two eucalypt clones.
(2010)Eucalypt trees are one of tree species used for the manufacturing of papers in South Africa. The manufacturing of paper consists of cooking the wood with chemicals until obtaining a pulp. The wood is made of different ... -
Statistical methods for longitudinal binary data structure with applications to antiretroviral medication adherence.
(2010)Longitudinal data tend to be correlated and hence posing a challenge in the analysis since the correlation has to be accounted for to obtain valid inference. We study various statistical methods for such correlated ... -
Linear model diagnostics and measurement error
(2010-09-07)The general linear model, the weighted linear model, and the generalized linear model are presented in detail. Diagnostic tools for the linear models are considered. In general the standard analysis for linear models does ... -
The application of multistate Markov models to HIV disease progression.
(2011)Survival analysis is a well developed area which explores time to single event analysis. In some cases, however, such methods may not adequately capture the disease process as the disease progression may involve ... -
Modelling longitudinal binary disease outcome data including the effect of covariates and extra variability.
(2011)The current work deals with modelling longitudinal or repeated non-Gaussian measurements for a respiratory disease. The analysis of longitudinal data for non-Gaussian binary disease outcome data can broadly be modeled ... -
Modelling longitudinally measured outcome HIV biomarkers with immuno genetic parameters.
(2011)According to the Joint United Nations Programme against HIV/AIDS 2009 AIDS epidemic update, there were a total of 33.3 million (31.4 million–35.3 million) people living with HIV worldwide in 2009. The majority of the ... -
Modelling volatility in financial time series.
(2011)The objective of this dissertation is to model the volatility of financial time series data using ARCH, GARCH and stochastic volatility models. It is found that the ARCH and GARCH models are easy to fit compared to the ... -
Statistical analysis of the incidence and mortality of African horse sickness in South Africa.
(2011)No abstract available. -
Estimation and analysis of measures of disease for HIV infection in childbearing women using serial seroprevalence data.
(2011)The prevalence and the incidence are two primary epidemiological parameters in infectious disease modelling. The incidence is also closely related to the force of infection or the hazard of infection in survival ... -
Imputation for nonresponse using the Annual Financial Statistics Survey.
(2011)In this dissertation, we focus on the Annual Financial Statistics (AFS) survey. This is a survey conducted by Statistics South Africa, the national statistics office of South Africa. The main purpose of this survey is ... -
Completion of an incomplete market by quadratic variation assets.
(2011)It is well known that the general geometric L´evy market models are incomplete, except for the geometric Brownian and the geometric Poissonian, but such a market can be completed by enlarging it with power-jump assets ... -
Multivariate time series modelling.
(2012)This research is based on a detailed description of model building for multivariate time series models. Under the assumption of stationarity, identification, estimation of the parameters and diagnostic checking for the ... -
Comparative approaches to handling missing data, with particular focus on multiple imputation for both cross-sectional and longitudinal models.
(2012)Much data-based research are characterized by the unavoidable problem of incompleteness as a result of missing or erroneous values. This thesis discusses some of the various strategies and basic issues in statistical ... -
A complex survey data analysis of TB and HIV mortality in South Africa.
(2012)Many countries in the world record annual summary statistics such as economic indicators like Gross Domestic Product (GDP) and vital statistics for example the number of births and deaths. In this thesis we focus on mortality ... -
Evaluation of strategies to combine multiple biomarkers in diagnostic testing.
(2012)A challenge in clinical medicine is that of correct diagnosis of disease. Medical researchers invest considerable time and effort to enhance accurate disease diagnosis. Diagnostic tests are important components in modern ... -
Multilevel modelling of HIV in Swaziland using frequentist and Bayesian approaches.
(2012)Multilevel models account for different levels of aggregation that may be present in the data. Researchers are sometimes faced with the task of analysing data that are collected at different levels such that attributes ...