Modele și metode statistice utilizate în studiul științelor vieții / Statistical models and methods used in life sciences

The doctoral thesis entitled “Statistical models and methods used in life sciences” addresses various interdisciplinary aspects at the intersection of engineering, mathematics and psychology. The work is organized in 5 chapters. Chapter 1 provides the motivation for this research and the current status of various research areas ranging from psychology to cryptography and natural language processing. Chapter 2 uses the written Romanian language as the subject of study and extracts interesting conclusions about statistical independence at the letter, m-gram, and word levels. lt also revisits essential statistical concepts such as Type ll statistical error. Previously obtained results are confirmed and reinforced through analysis of the literary corpus. Chapter 3 transitions to the field of psychology, demonstrating a remarkable example of interdisciplinarity, where information theory and statistics find applicability in a purely humanistic domain. Chapter 4 shifts the research focus to another fertile area, chaos-based cryptography. The author's interest in this field dates back to their undergraduate studies at UPB, and the investigations in this chapter build upon and extend the previously published results, incorporating notions of singularity or observability. Chapter 5 presents the conclusions of the work, summarizing the main original results achieved throughout the doctoral studies.