Data structures are key pillars for optimizing computational efficiency, as they contribute in no small measure to enhancing the "speed" in the accessing and subsequent processing of data. The need for enhancing speed is critical for almost all applications and domains, and this is most relevant when real-time or near real-time efficiency is desired. This thesis proposes the use of "Adaptive" Data-Structures (ADSs) that invoke reinforcement learning schemes from the theory of Learning Automata (LA). These operate in conjunction with select reorganization rules to update themselves as they receive queries from the Environment of interaction. The result of such a process is the subsequent minimization of the cost associated with query accesses. The Environments under consideration are those that exhibit a so-called "locality of reference", and are referred to as Non-stationary Environments (NSEs). A hierarchy of data "sub"-structures is used to design Singly-Linked Lists (SLLs) on Singly-Linked Lists, which thus contain outer and sub-list contexts. The elements that are more likely to be accessed together are grouped within the same sub-context, while the sub-lists themselves are moved "en masse" towards the head of the listcontext by following a reorganization strategy. The Object Migration Automaton (OMA) family of reinforcement schemes are employed to capture the probabilistic dependence of the elements in the data structure as it receives query accesses from the Environment. The Enhanced Object Migration Automaton (EOMA), the Pursuit Enhanced Object Migration Automaton (PEOMA), and the Transitivity Pursuit Enhanced Object Migration Automaton (TPEOMA) have each been individually incorporated into the hierarchical SLLs. The consequent results are currently the state-of-the-art methods for adaptive SLLs operating in NSEs. iii Finally, I will want to especially thank my Uncle and Aunt, Achu and Blessing Bisong, for their love, care, support and encouragement throughout the time of this thesis, and indeed, my stay in Canada. They have been a rock in my life. I am grateful to the faculty, the staff and the friends I made at the School of Computer Science at Carleton. They made my stay here enjoyable and fulfilling. iv Bibliography Appendices A OMA-Augmented Hierarchical SLLs Results B EOMA-Augmented Hierarchical SLLs Results C PEOMA-Augmented Hierarchical SLLs Results D TPEOMA-Augmented Hierarchical SLLs Results viii