Thesis (M.S.)--University of North Texas, Dec., 2009. / Title from title page display. Includes bibliographical references.

The use and application of modeling and simulation (M&S) is pervasive in today's world. A key component in the application of models is to conduct appropriate verification and validation (V&V). V&V is conducted to make sure the model represents reality to the appropriate level of detail based on the questions posed. V&V techniques are well documented within the literature for observable systems, i.e. required data can be collected from the operations of the real system for comparison with the simulation results; however, V&V techniques for non-observable systems are limited to subjective validation. This subjective validation can be applied to the simulation outputs, operational validation, or towards the model development, conceptual validation. Oftentimes subjective operational validation of the simulation is the primary source of validation efforts. It is shown in this thesis that the sole reliance on subjective operational validation of the simulation can easily lead to the inaccurate acceptance of a model. In order to improve M&S practices for the representation of non-observable systems, models must be developed in a methodological manner that provides a traceable and defensible argument behind the model’s representation of reality. Though there is growing discussion within the recent literature, few methods exist on proper conceptual model development and validation. The research objective of this thesis is to identify a methodology to develop a model in a traceable and defensible manner for a system or system of systems that is non-observable. To address this research objective the proposal will address eight aspects of model development. The first is to define a set of terms that are common vernacular in the field of M&S. This is followed by the assessment of what defines a ‘good’ model and how to determine if the model is ‘good’ or not. This leads to a review of V&V and the observation that subjective validation in isolation is not sufficient for model validation. Next, a review of model development procedures is conducted and analyzed against a set of criteria. A selection is made using the Analytic Hierarchy Process (AHP). A procedure developed by Balci in 1986 is selected for the use in development of models for non-observable systems. Specific steps within Balci's 1986 procedure are investigated further to determine appropriate techniques that should be used when developing models of non-observable systems. These steps are system and objective definition, conceptual model, communicative model, and experimental models and results. Five techniques are identified in the literature that can be applied to system and objective definition: Soft Systems Methodology, Requirements Engineering, Unified Modeling Language, Systems Modeling Language, and Department of Defense Architecture Framework. These techniques are reviewed and selection is made using AHP. The System Modeling Language (SysML) is selected as the best technique to perform System an Objective Definition. Significant resources are devoted to the study of conceptual model development. Proposed in this thesis is a process to decompose the impacts of the system and apply subjective weightings in order to identify aspects of the system with significant importance. This approach enables the modeling of the system in question to the appropriate level of fidelity based on the identified importance of the system impacts. Additionally, this process provides traceability and defensibility of the final model form. Communicative model development is rarely addressed in the literature; however, many of the techniques used in system and objective definition can be applied to developing a communicative model. A similar study to the system and objective definition, AHP was utilized to make a selection. It was concluded that the Unified Modeling Language provides the best tool for creating a communicative model. In the final step, experimental models and results, the literature was found to be rich in techniques. A gap was found in the analysis of the outputs of stochastic simulations. Four questions resulted: 'which stochastic measures should be used in analyzing a stochastic simulation?', 'how many replications are required for an accurate estimation of the stochastic measure?', which least squares method should be used in the regression of a stochastic response?, and 'how many replications are required for an accurate regression of a stochastic measure? Heuristics are presented for each of these questions. A proof of concept is provided on the methodology developed within this thesis. The selected scenario is a Humanitarian Aid/Disaster Relief Mission, where the U.S. Navy has been tasked with distributing aid in an effective manner to the affected population. Upon application of the proposed methodology, it was observed that subjective decomposition and weighting of the scenario proved to be a useful tool for guiding and justifying the form of the eventual model. Shortcomings of the methodology were identified. The primary shortcomings identified were the linking of information between the steps of the model development procedure, and the difficulty in correctly identifying the structure of the system impacts decomposition. The primary contribution of this thesis is to the field of M&S. Contributions are made to the practice of conceptual model development, a growing discussion within the literature over the past several years. The contribution to conceptual model development will aid in the development models for non-observable systems. Additional contributions are made to the analysis of stochastic simulations. The methodology presented in this thesis will provide a new and robust method to develop and validate models in a traceable and defensible manner.

The science of behavior analysis relies heavily on direct observation. Human observers are typically used to measure behavior in applied settings. Although the use of human observers is beneficial in many regards, it also presents challenges. Of primary concern is the extent to which the data generated by observers actually corresponds to the behavioral events of interest, and the implications this may have in terms of replication. This study assessed the effects that labels, definitions, and examples and non-examples of two different modalities had on observer accuracy, consistency, and agreement. Results showed that current practices in observer training may require refinement to ensure high observer accuracy, consistency, and agreement. Suggestions for how to improve the desired stimulus control of observers are provided.

Aim: This study explores what type of information patients and nurses share with, or provide to, each other, and whether or not the information received was relevant and sufficient for their needs. Background: Information exchange, as part of shared decision-making, is advocated in policy and practice throughout the healthcare sector. Much of the literature on information exchange relates to one-to-one consultations with consultants or GPs. To date, no studies have explored information exchange between patients and nurses in ward settings. Nursing literature on patients’ information needs focuses on one-way information provision from nurses to patients, rather than on two-way information exchange between patients and nurses. Methods: Interactions between patients and nurses were observed and audio-recorded using a remotely controlled audio-recording system. Semi-structured individual face-to-face interviews were then conducted to clarify and add to the observation data. A multiple case study design was used for this study: each case comprised one patient, the nurses caring for that patient, and the interactions between them. A pilot study was undertaken to inform the methods for recruitment and data collection for the main study. Results: The pilot study comprised five cases (patients n=5, nurses n=3). Changes to the recruitment strategy for the main study included surgical patients being invited to participate in the same way as medical patients. There were no difficulties with the data collection methods. The main study comprised nineteen cases (patients n=19, nurses n=22). Information exchange seemed unfamiliar to ward-based nurses. The findings show that information exchange may not be a one-off event but a complex series of interactions. Patients did not distinguish between clinical and non-clinical information in the same way as nurses. Primary reasons for patients’ hospital admission were not discussed and nurses did not share information about nursing interventions. The relevance for patients and nurses differed; patients generally wanted information for reducing anxiety and socialization; nurses wanted information for assessment and care planning. In terms of sufficiency, observation sessions highlighted that insufficient information was provided, often due to lost opportunities and paternalistic practice. However, the majority of patients and nurses perceived that they had exchanged sufficient information. Conclusion: This multiple case study provides insights into the type, relevance and sufficiency of information for patients and nurses in ward settings. In ward settings, information exchange as conceptualised by Charles et al. (1997 and 1999) may be difficult to achieve due to the complexity of patient/nurse interactions. Therefore, there are implications for policy makers as policies are not context specific. However, information exchange may be helpful for reducing patients’ anxieties. The concepts of shared decision-making and information exchange are not part of ward-based cultures and philosophies, which suggests implications for patient and nurse education. Research on information exchange between patients and nurses in other ward contexts may contribute to further understanding of information exchange in ward settings.

In this dissertation, I investigate whether the conceptualisation of computerised technological phenomena is influenced by social variables, in particular exposure to the computer. The conceptualisation and behaviour of a group of students majoring in technology-related fields were studied. Through the application of Conceptual Blending Theory, the multi-modal desktop metaphorical blend (DMMB) (as an electronic representation of an actual office desktop) was focused on. The participants were provided with tasks with the aim of determining whether they conceptualise the electronic desktop as a literal ‘thing-in-itself’ or as an e-version of their actual desks. The intent was to examine to what extent social variables, especially exposure, motivate the nature of the conceptualisation. Therefore, it is hypothesised that exposure, regarded as the primary variable in this study, influences conceptualisation of the DMMB to the extent where the it either loses its metaphoric quality in participants, who maintain regular and prolonged exposure to the computer, or retains the metaphoric quality of the DMMB in participants, who are not exposed to the computer on a regular and prolonged basis. Two groups were distinguished based on the extent of the individual participants’ exposure to computer technology, namely a high-exposure group and a low-exposure group. A mixed method approach was used to test and analyse data collected from individual participants, as well as from the high- and low-exposure groups. Methods used to test these hypotheses included questionnaires, word association (a conceptual task), controlled observation (a behavioural task), and interviews. The resulting data were analysed by means of a thematic interview analysis and non-parametric statistical tests. / Linguistics and Modern Languages / M.A. (Linguistics)

In this dissertation, I investigate whether the conceptualisation of computerised technological phenomena is influenced by social variables, in particular exposure to the computer. The conceptualisation and behaviour of a group of students majoring in technology-related fields were studied. Through the application of Conceptual Blending Theory, the multi-modal desktop metaphorical blend (DMMB) (as an electronic representation of an actual office desktop) was focused on. The participants were provided with tasks with the aim of determining whether they conceptualise the electronic desktop as a literal ‘thing-in-itself’ or as an e-version of their actual desks. The intent was to examine to what extent social variables, especially exposure, motivate the nature of the conceptualisation. Therefore, it is hypothesised that exposure, regarded as the primary variable in this study, influences conceptualisation of the DMMB to the extent where the it either loses its metaphoric quality in participants, who maintain regular and prolonged exposure to the computer, or retains the metaphoric quality of the DMMB in participants, who are not exposed to the computer on a regular and prolonged basis. Two groups were distinguished based on the extent of the individual participants’ exposure to computer technology, namely a high-exposure group and a low-exposure group. A mixed method approach was used to test and analyse data collected from individual participants, as well as from the high- and low-exposure groups. Methods used to test these hypotheses included questionnaires, word association (a conceptual task), controlled observation (a behavioural task), and interviews. The resulting data were analysed by means of a thematic interview analysis and non-parametric statistical tests. / Linguistics and Modern Languages / M.A. (Linguistics)