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This thesis is concerned with the problem of selection of important variables in Principal Component Analysis (PCA) in such a way that the selected subsets of variables retain, as much as possible, the overall multivariate structure of the complete data. Throughout the thesis, the criteria used in order to meet this requirement are collectively referred to as measures of Multivariate Association (MVA). Most of the currently available selection methods may lead to inappropriate subsets, while Krzanowskis (1987) M(subscript)2-Procrustes criterion successfully identifies structure-bearing variables particularly when groups are present in the data. Our major objective, however, is to utilize the idea of multivariate association to select subsets of the original variables which preserve any (unknown) multivariate structure that may be present in the data.The first part of the thesis is devoted to a study of the choice of the number of components (say, k) to be used in the variable selection process. Various methods that exist in the literature for choosing k are described, and comparative studies on these methods are reviewed. Currently available methods based exclusively on the eigenvalues of the covariance or correlation matrices, and those based on cross-validation are unsatisfactory. Hence, we propose a new technique for choosing k based on the bootstrap methodology. A full comparative study of this new technique and the cross-validatory choice of k proposed by Eastment and Krzanowski (1982) is then carried out using data simulated from Monte Carlo experiment.The remainder of the thesis focuses on variable selection in PCA using measures of MVA. Various existing selection methods are described, and comparative studies on these methods available in the literature are reviewed. New methods for selecting variables, based of measures of MVA are then proposed and compared ++ / among themselves as well as with the M(subscript)2-procrustes criterion. This comparison is based on Monte Carlo simulation, and the behaviour of the selection methods is assessed in terms of the performance of the selected variables.In summary, the Monte Carlo results suggest that the proposed bootstrap technique for choosing k generally performs better than the cross-validatory technique of Eastment and Krzanowski (1982). Similarly, the Monte Carlo comparison of the variable selection methods shows that the proposed methods are comparable with or better than Krzanowskis (1987) M(subscript)2-procrustes criterion. These conclusions are mainly based on data simulated by means of Monte Carlo experiments. However, these techniques for choosing k and the various variable selection techniques are also evaluated on some real data sets. Some comments on alternative approaches and suggestions for possible extensions conclude the thesis.

In this dissertation an attempt was made to uncover the source of verbal associations. The investigation focused on establishing the locus of representation for associative relationships in the cognitive system and whether this locus is different from that for semantic relationships. A picture naming task and an object decision task were used within the standard priming paradigm, in which the target is preceded by a prime. A dual-level model was proposed in which associative relatedness is represented at a lemma level that connects the lexical form representation of a word to its semantic information. According to this model an interaction between associative and categorical relatedness should occur in picture naming, but not in object decision, when primes and targets share both relationships, and this is what was observed. To investigate the mechanisms of associative priming, asymmetrically associated prime-target pairs were used to create two situations. In the forward priming condition the target was an associate of the prime (e.g., brick-house), and in the backward priming condition the prime was an associate of the target (e.g., babyrattle). Unexpectedly, facilitation was observed for backward priming at the short SOA in picture naming. Because no effect was observed for this condition in the object decision task, and given that forward priming produced facilitation in both tasks spreading activation was upheld as the mechanism for associative priming. In order to investigate whether the source of the relationship between associates might be in their latent semantic content, the impact of instrument relationships (e.g., grinder-coffee), script relationships (e.g., zoo-tiger), and proximity in multidimensional semantic space were also investigated in the picture naming task. Items that were close in semantic space, but did not share any semantic relationships, produced the same priming pattern as category co-ordinates in picture naming (i.e., interference), while instrumental and script relationships did not produce a priming pattern that matched either that observed for associative or categorical relatedness. These results were taken to indicate that the source of associative relationships is in the co-occurrence of words in the language, which further supported the main claim of a dual-level model where information about verbal associations is stored outside semantic memory.

This study has resulted from the author's interest and participation in the activities of the A.C.T. Primary Principals' Association over the past six years. For the last three years of the twelve-year period covered by the study he was General Secretary of the Association, and thus had access to the minutes, reports and correspondence which had accumulated since the inception of the Association. Additional information has been obtained through discussions, reminiscences, letters and taperecordings from members and others who were actively involved in the activities of the Association. The History of the Association has been divided into four stages, corresponding to: 1. The inaugural period, under the direction of New South Wales. 2. The period of maximum growth. 3. The beginning of the independent A.C.T. Schools System. 4. The reorganisation of the Association. The main topics which were discussed within each period are analysed, together with the reactions of members to the circumstances which caused those topics to be emphasised, The analysis has shown that over the twelve-year period there has been: 1. A series of organisational changes in the structure of the Association as its membership has increased. 2. A significant trend away from the discussion of topics which could be classified as Managerial and towards subjects which could be regarded as Educational. 3. An increasing use of Guest Speakers at meetings and conferences. 4. A gradual change in the objectives of the Association and in the nature of the organisations to which it has related. 5. Only a very small percentage of members who have held Executive Office in the Association. The comments of individuals who have been involved with the Association over a period of years are used to assess its strengths and weaknesses, and suggestions are made regarding ways in which the structure of the organisation might possibly be improved. An examination has been made of the Association as a model-type, and throughout the study there is discussion as to how its performance equates with the findings of current literature on Organisational Theory. A recommendation is made that a review of the stated aims of the Association be undertaken, and that a Constitution be developed.

Thesis (M. Ed.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

This research addresses the functional characteristics of a single organization. It specifically investigates one of the largest festival organizations in the United States, The Portland Rose Festival Association (PRFA). In this case, three groups within the PRFA are its foundation: the paid staff, the executive committee, and the volunteer directors. This study identifies and analyzes the functionality characteristics of this organization. Swanson's (1996) theory of performance variables is used to assess and benchmark the PRFA. He provides five key areas in which functional, effective, and successful groups are proficient. These five areas are: mission/goal, capacity, systems design, motivation, and expertise. The research is qualitative and quantitative in nature by implementing two primary methods- interviews and questionnaires. Phase one consists of interviews from the eleven staff members. The research discovers that the PRFA has numerous strengths. The weaknesses the staff mentioned have been acknowledged by management and are being improved upon or solved. As a result of this phase, the PRFA was assessed as a functional organization. Phase two determines the level of functionality according to appropriate organizational characteristics. The characteristics correspond to Swanson's performance variables. This phase was conducted through questionnaires to the staff members, executive committee, and volunteer directors. The research indicated that the "mission/goal" organizational characteristic received the highest combined mean. Although all areas were ranked very high, responses on the "expertise" questions indicate an area for improvement. Finally, the study discovers that the three groups are relatively familiar with each other. / Graduation date: 2000

Project (D. Miss.)--Trinity Evangelical Divinity School, 1984. / Abstract. Includes bibliographical references (leaves 166-172).

Thesis (Ph. D.)--Ohio State University, 2006. / Full text release at OhioLINK's ETD Center delayed at author's request

Thesis (M.S.)--University of Delaware, 2006. / Principal faculty advisor: Neal Zondlo, Dept. of Chemistry & Biochemistry. Includes bibliographical references.