• Advances in random forests with application to classification 

      Pretorius, Arnu (Stellenbosch : Stellenbosch University, 2016-12)
      ENGLISH SUMMARY : Since their introduction, random forests have successfully been employed in a vast array of application areas. Fairly recently, a number of algorithms that adhere to Leo Breiman’s definition of a random ...
    • An analysis of income and poverty in South Africa 

      Malherbe, Jeanine Elizabeth (Stellenbosch : University of Stellenbosch, 2007-03)
      The aim of this study is to assess the welfare of South Africa in terms of poverty and inequality. This is done using the Income and Expenditure Survey (IES) of 2000, released by Statistics South Africa, and reviewing ...
    • The application and testing of smart beta strategies in the South African market 

      Viljoen, Jacobus (Stellenbosch : Stellenbosch University, 2018-03)
      ENGLISH SUMMARY: Smart Beta portfolios have recently prompted great interest both from academic researchers and market practitioners. Investors are attracted by the performances produced by these portfolios compared to the ...
    • Application of cluster analysis and multidimensional scaling on medical schemes data 

      Roux, Ian (Stellenbosch : Stellenbosch University, 2008-12)
      Cluster analysis and multidimensional scaling (MDS) methods can be used to explore the structure in multidimensional data and can be applied to various fields of study. In this study, clustering techniques and MDS methods ...
    • An application of copulas to improve PCA biplots for multivariate extremes 

      Perrang, Justin (Stellenbosch : Stellenbosch University, 2018-12)
      ENGLISH SUMMARY : Principal Component Analysis (PCA) biplots is a valuable means of visualising high dimensional data. The application of PCA biplots over a wide variety of research areas containing multivariate data is ...
    • An application of geometric data analysis techniques to South African crime data 

      Gurr, Benjamin William (Stellenbosch : Stellenbosch University, 2016-12)
      ENGLISH SUMMARY : Due to the high levels of violent crime in South Africa, improved methods of analysis are required in order to better scrutinize these statistics. This study diverges from traditional multivariate data ...
    • Application of statistics and machine learning in healthcare 

      Van der Merwe, Schalk Gerhardus (Stellenbosch : Stellenbosch University, 2019-04)
      ENGLISH SUMMARY : Clinical performance and cost efficiency are key focus areas in the healthcare industry, since providing quality and affordable healthcare is a continuing challenge. The goal of this research is to use ...
    • Aspects of copulas and goodness-of-fit 

      Kpanzou, Tchilabalo Abozou (Stellenbosch : Stellenbosch University, 2008-12)
      The goodness-of- t of a statistical model describes how well it ts a set of observations. Measures of goodness-of- t typically summarize the discrepancy between observed values and the values expected under the model ...
    • Aspects of model development using regression quantiles and elemental regressions 

      Ranganai, Edmore (Stellenbosch : Stellenbosch University, 2007-03)
      ENGLISH ABSTRACT: It is well known that ordinary least squares (OLS) procedures are sensitive to deviations from the classical Gaussian assumptions (outliers) as well as data aberrations in the design space. The two major ...
    • Aspects of multi-class nearest hypersphere classification 

      Coetzer, Frances (Stellenbosch : Stellenbosch University, 2017-12)
      ENGLISH SUMMARY : Using hyperspheres in the analysis of multivariate data is not a common practice in Statistics. However, hyperspheres have some interesting properties which are useful for data analysis in the following ...
    • Aspects of some exotic options 

      Theron, Nadia (Stellenbosch : University of Stellenbosch, 2007-12)
      The use of options on various stock markets over the world has introduced a unique opportunity for investors to hedge, speculate, create synthetic financial instruments and reduce funding and other costs in their trading ...
    • Assessing the influence of observations on the generalization performance of the kernel Fisher discriminant classifier 

      Lamont, Morné Michael Connell (Stellenbosch : Stellenbosch University, 2008-12)
      Kernel Fisher discriminant analysis (KFDA) is a kernel-based technique that can be used to classify observations of unknown origin into predefined groups. Basically, KFDA can be viewed as a non-linear extension of Fisher’s ...
    • Bayesian approaches of Markov models embedded in unbalanced panel data 

      Muller, Christoffel Joseph Brand (Stellenbosch : Stellenbosch University, 2012-12)
      ENGLISH ABSTRACT: Multi-state models are used in this dissertation to model panel data, also known as longitudinal or cross-sectional time-series data. These are data sets which include units that are observed across two ...
    • Binary classification trees : a comparison with popular classification methods in statistics using different software 

      Lamont, Morné Michael Connell (Stellenbosch : Stellenbosch University, 2002-12)
      ENGLISH ABSTRACT: Consider a data set with a categorical response variable and a set of explanatory variables. The response variable can have two or more categories and the explanatory variables can be numerical or ...
    • Biplot methodology for analysing and evaluating missing multivariate nominal scaled data 

      Nienkemper-Swanepoel, Johane (Stellenbosch : Stellenbosch University, 2019-12)
      ENGLISH ABSTRACT: This research aims at developing exploratory techniques that are specifically suitable for missing data applications. Categorical data analysis, missing data analysis and biplot visualisation are the ...
    • A brief introduction to basic multivariate economic statistical process control 

      Mudavanhu, Precious (Stellenbosch : Stellenbosch University, 2012-12)
      ENGLISH ABSTRACT: Statistical process control (SPC) plays a very important role in monitoring and improving industrial processes to ensure that products produced or shipped to the customer meet the required specifications. ...
    • Calculation aspects of the European Rebalanced Basket Option using Monte Carlo methods 

      Van der Merwe, Carel Johannes (Stellenbosch : University of Stellenbosch, 2010-12)
      ENGLISH ABSTRACT: Life insurance and pension funds offer a wide range of products that are invested in a mix of assets. These portfolios (II), underlying the products, are rebalanced back to predetermined fixed proportions ...
    • Classification in high dimensional data using sparse techniques 

      Stulumani, Agrippa (Stellenbosch : Stellenbosch University, 2019-04)
      ENGLISH SUMMARY : Traditional classification techniques fail in the analysis of high-dimensional data. In response, new classification techniques and accompanying theory have recently emerged. These techniques are natural ...
    • Classifying yield spread movements in sparse data through triplots 

      Van der Merwe, Carel Johannes (Stellenbosch : Stellenbosch University, 2020-03)
      ENGLISH SUMMARY : In many developing countries, including South Africa, all data that are required to calculate the fair values of financial instruments are not always readily available. Additionally, in some instances, ...
    • Comparison of methods to calculate measures of inequality based on interval data 

      Neethling, Willem Francois (Stellenbosch : Stellenbosch University, 2015-12)
      ENGLISH ABSTRACT: In recent decades, economists and sociologists have taken an increasing interest in the study of income attainment and income inequality. Many of these studies have used census data, but social surveys ...