Samuel was retained as a teaching assistant and a demonstrator by the department of mathematics, KNUST from 2005 until 2007 when he earned the prestigious VLIR scholarship to pursue his master’s degree in UHasselt. During his time as a teaching assistant, he was assigned to grade weekly assignments and also carried out linear algebra and introduction to pure mathematics tutorial classes for undergraduate students from various departments in the college of science. He also assisted final year students with their undergraduate project works. Iddi had a brief teaching experience with Lawsec and Ko Senior Secondary School between 2000 and 2001 where he taught core and elective mathematics, integrated science, and physics.

As a Ph.D. research assistant at the Interuniversity Institute for Biostatistics and Statistical Bioinformatics (I-BioStat), KU Leuven, Samuel was responsible for conducting research for international publications and also provided statistical advice, analysis, and consultation for members of the Faculty of Medicine. His research interest was broadly on hierarchical and marginalized models for correlated, overdispersed, zero-inflated models for non-Gaussian longitudinal and repeated measures outcomes with application to life science studies. In addition to his primary lines of research, Samuel was also interested in joint modeling of mixed outcomes, pseudo-likelihood estimation techniques, and infectious diseases and had conducted research in these areas. His work led to a number of scientific publications in internationally renowned statistical and probability journals. He has also presented his work at several international conferences and seminars worldwide.

In January 2014, Samuel received an appointment as a Lecturer in the Department of Statistics and Actuarial Science, University of Ghana, Legon. By May 2016, he was promoted to Senior Lecturer in the same department. He has handled the following undergraduate and graduate-level courses: Advanced Data Analysis in Public Health (Ph.D.), Advanced Quantitative Research Methods (Ph.D.), Computing for Statistics (Ph.D.), Multivariate Analysis (MSc), Research Methods (MSc), Advanced Data Analysis (MSc), Survival Models (MSc), Multivariate Methods (BSc.), Survival Analysis and Modeling, Probability I, II (BSc.) and Probability Distributions (BSc.). He also supervises undergraduate projects and graduate thesis in statistics. Currently, Samuel completed a postdoctoral research study at the Alzheimer's Therapeutic Research Institute (ATRI), Keck School of Medicine of the University of Southern California, USA with the Biostatistics team. He is developing and applying statistical methodology for longitudinal data from natural history studies of neurological diseases with the following key objectives; (i) predicting the course of Alzheimer's and Parkinson's diseases as measured by imaging and fluid biomarkers, and cognitive and functional markers; (2) predicting longitudinal Alzheimer's disease (AD) markers and clinical diagnosis; (3) predicting response to treatment; (4) optimal design of clinical trials of AD.

Samuel believes in the existence of a supreme God and derives his spiritual nourishment from the Church of Pentecost in Ghana and San Diego. He has also worshiped with the Christ Centered Church, Leuven (CCCL) in Belgium in the past. He enjoys playing football during the weekend and also loves to be up to date with the latest sports news and the newest in the world of technology.