Missing Data Topic of Statistician’s Inaugural Lecture
Statistics Professor in the School of Mathematics, Statistics and Computer Science, Professor Shaun Ramroop, was honoured to present his inaugural lecture on the topic of missing data within the ambit of flexible statistical modelling.
Ramroop’s inauguration to the rank of full professor was held online on Tuesday, 26 July 2022.
He explained that even in a well-designed and controlled study, missing data occurs in almost all research. ‘Missing data can reduce the statistical power of a study and can produce biased estimates, leading to invalid conclusions,’ he said. ‘This warrants the need to review problems and types of missing data, along with the techniques for handling missing data.’
During his lecture, Ramroop illustrated the mechanisms by which missing data occurs, and interrogated the methods for handling the missing data within the ambit of flexible statistical modelling.
‘The classical methods range from complete case analysis (CC), last observation carried forward (LOCF) and mean value imputation, whilst the more modern techniques include Multiple Imputation (MI), Multiple Imputation via Chained Equation (MICE), Inverse Probability Weighting (IPW) and Multiple Subset Correspondence analysis,’ he said, whilst also elaborating on the merits and demerits of the various techniques.
Ramroop - who is based on UKZN’s Pietermaritzburg campus - completed his BSc (Statistics and Applied Mathematics) in 1995 and his BSc Hons (Statistics) in 1996 before being employed as a biometrician in 1997 at the South African Sugar Research Centre in Durban.
His academic journey started when he joined the then University of Natal (now UKZN) as a tutor in 2001. Upon completion of his MSc in Statistics in 2002 with UNISA, he began his PhD studies through UKZN, which was awarded in 2007. In the same year, he was promoted to lecturer, becoming a senior lecturer in 2011. In 2016, he achieved Associate Professorship and was promoted to Academic Leader for Statistics in 2018. At the end of 2020, he was promoted to Full Professor.
One award of which Ramroop is particularly proud is being recognised as one of the top 30 emerging researchers at UKZN in 2010. Another is his Distinguished Teacher Award within the College of Agriculture, Engineering and Science which he received in 2015. ‘One of the standout features of Shaun Ramroop is his teaching ability,’ said Dean and Head of the School of Mathematics, Statistics and Computer Science, Professor Delia North.
Ramroop has graduated 25 MSc and six PhD students and has published more than 50 papers in accredited journals. His research areas include biostatistics and applied statistics in modelling and analysing business, health, education, environmental, agricultural and social systems. His research has led to the application of novel models which consequentially gives meaningful inference to help the underwriting of policies and extending the existing body of knowledge in those research areas.
Ramroop is actively involved in statistical consultation and was the chief consultant to the Msunduzi Municipality in their 2015-16 living conditions survey. He was also the chief statistician to the greater Sekhukhune District municipality in their customer satisfaction survey from 2012-2015, and the Silulumanzi Water projects from 2013-2016.
‘Ramroop’s standing and recognition as a researcher and academic are evident from the work he performs at a national level for leading, strategic education and research organisations in South Africa. He has the mindset to serve his discipline,’ said North.
Words: Sally Frost