| This exploratory study investigates the hypothesis that case-based reasoning (CBR) systems have advantages over rule-based reasoning (RBR) systems in providing automated support for Tier-2 help desk operations. The literature suggests that rule-based systems are best suited for problem solving when the system being analyzed is a single-purpose, specialized system and the rules for solving the problems are clear and do not change with high frequency. Case-based systems, because of their ability to offer alternative solutions for a given problem, give help-desk technicians more flexibility. Specifically, this dissertation aims to answer the following questions: (1) Which paradigm, rule-based or case-based reasoning, results in more precise solutions to problems when compared to the solutions derived from system manuals? (2) Which paradigm, rule-based or case-based reasoning, is more convenient to maintain in terms of knowledge modification (i.e. addition, deletion, or modification of rules/cases)? (3) Which paradigm, rule-based or case-based reasoning, enables help-desk technicians to solve problems in shorter time, and therefore at lower cost?;This is an exploratory study based on data collected from field experiments. RBR and CBR based prototypes were set up to support Tier-2 help desk operations. Trained help desk operators used the system to solve a set of benchmark problems. Data collected from this exercise was analyzed to answer the three research questions.;This exploratory study supported the hypothesis that the case-based paradigm is better suited for use in help desk environments at the Tier-2 level than is the rule-based paradigm. The case-based paradigm, because of its ability to offer alternative solutions for a given problem, gave the help-desk technician flexibility in applying a solution. Alternatively, the rule-based paradigm provided a solution if, and only if, a rule existed for a solution meeting the exact problem specifications. Further, in the absence of a rule, problem research time, using the rule-based paradigm, extended the time required to formulate a solution thereby increasing the cost.;This research provided sufficient information to show that the help-desk knowledge based system utilizing the case-based shell provided better overall solutions to problems than did the rule-based shell. |
