• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 216
  • 68
  • 62
  • 49
  • 21
  • 14
  • 13
  • 10
  • 9
  • 8
  • 3
  • 2
  • 2
  • 2
  • 2
  • Tagged with
  • 543
  • 104
  • 73
  • 59
  • 55
  • 55
  • 54
  • 49
  • 42
  • 37
  • 37
  • 36
  • 35
  • 34
  • 34
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

An assessment of urban residents' knowledge and appreciation of the intangible benefits of trees in two medium sized towns in South Africa

Chinyimba, Abby January 2013 (has links)
In order to meet the different public needs and requirements of contemporary urban society, a better understanding of public perceptions, appreciation and knowledge of the assorted values derived from urban trees is beneficial for improved urban greening. Thus, this study carried out an assessment of urban residents’ knowledge and appreciation of the benefits of trees and the role they play in enhancing the quality of life in urban systems. The study primarily focused on the intangible benefits (also referred to as cultural and regulating services) of urban trees, because most research to date in South Africa on trees and the benefits derived from them is biased towards the provisioning services of trees in rural areas. The significance and contribution of the intangible benefits of trees in urban systems is often underestimated and not seriously taken into account by urban planners, policy makers and other key decision makers. The study was conducted in three different residential settlement types (formal townships, RDP settlements and informal settlements) in two towns in the Limpopo Province in South Africa, namely Bela-Bela and Tzaneen. Findings revealed that the intangible benefits of trees are seen to play a significant role in improving both residents’ quality of life and the environmental conditions in cities, including the preservation of biodiversity. Findings also showed that urban residents had strong spiritual connections with trees and placed considerable cultural and historical importance on specific tree species and individual trees. Urban residents in both towns had moderate knowledge of the intangible benefits of trees based on the knowledge score that was created for the purposes of this study. Fifty seven percent of the residents had ‘reasonable’ knowledge of some of the intangible benefits of trees, while 43% had low levels of knowledge. That said, the majority of residents demonstrated high appreciation (98%) of the intangible benefits of trees (especially social and cultural values), with few residents not recognising these, suggesting that knowledge does not necessarily lead to appreciation. Age and level of education were found to influence knowledge of the intangible benefits of trees. A large proportion (86%) of residents who possessed tertiary level qualifications had more knowledge of the intangible benefits of trees as compared to residents with no formal education. Findings also revealed that younger respondents (60%) had more knowledge of the intangible benefits of trees. Factors that influenced appreciation of the intangible benefits of trees included links to crime, peoples’ value systems (their pro-environmental and altruistic values) and residential settlement type. Sixty five percent of residents in both towns felt that urban street trees and trees in public spaces attract criminals and promote crime, while 67% of RDP and 96% of informal township residents did not use or appreciate the social and recreational benefits of trees mainly because of the absence or long distances to public parks. A Willingness To Pay (WTP) survey revealed that a high proportion of residents in Bela-Bela (86%) were WTP a small annual fee in order to sustain greening initiatives in their communities compared to the residents in Tzaneen (53%). In terms of the planting and retention of trees, it was found that 300 households in both study towns had planted and retained a total of 1 615 trees in spite of the various factors that negatively influenced planting and retention of trees such as residency time and tenure security. The majority (66%) of informal township residents said tenure security was an important factor to consider when making tree planting decisions, while this was not an issue for formal township and RDP residents. Policy implications and recommendations are presented to help municipalities and urban planners improve and develop effective policies and programmes that will enable implementation of sustainable urban greening programmes
62

Numerical and empirical studies of option pricing

Stilger, Przemyslaw January 2014 (has links)
This thesis makes a number of contributions in the derivative pricing and risk management literature and to the growing literature that exploits information embedded in option prices. First, it develops an effective numerical scheme for importance sampling scheme of Fouque and Tullie (2002) based on a 2-dimensional lookup table of stock price and time to maturity that dramatically improves the speed of this importance sampling scheme. Second, the thesis presents an application of this importance sampling scheme in a Multi-Level Monte Carlo simulation. Such combination yields greater variance reduction compared to Multi-Level Monte Carlo or importance sampling alone. Third, it demonstrates how the Greeks can be computed using the Likelihood Ratio Method based on characteristic function, and how combining it with importance sampling leads to a significant variance reduction for the Greeks. Finally, it documents the positive relationship between the risk-neutral skewness (RNS) and future realized stock returns that is driven by the underperformance of highly negative RNS portfolio. The results provide strong evidence that the underperformance of stocks with the lowest RNS is driven by those stocks that are associated with a higher hedging demand, relative overvaluation and are also too costly or too risky to sell short. Moreover, by decomposing RNS into its systematic and idiosyncratic components, this thesis shows that the latter drives the positive relationship with future realized stock returns.
63

Relationship of Leadership Importance Ratings and Leadership Competency Ratings Across Adjacent Management Levels

Goldman, Joshua L. (Joshua Lee) 05 1900 (has links)
Effective leadership can and does influence organizational performance. The Executive Success Profile, a multi-rater feedback instrument, was used to gather perception data on 51 executives and 310 senior managers of a large Fortune 500 electronics manufacturing company in regards to three critical leadership dimensions: visionary thinking, empowering others, and global perspective. Paired t-tests were run to compare the means of the two samples. Significant differences were found between executives and senior managers on the perceived importance of and ability to perform on the empowering others dimension. Additionally, correlational measures indicate a statistically significant relationship between importance and competence ratings on the empowering others and global perspective dimensions for executives, and on the empowering others dimension for senior managers.
64

Factors that influence the retention of B players in a South African professional service firm

Keshava, Naidu 04 June 2011 (has links)
Research in the field of retention has been dominated by studies focused on retention of highly talented employees or A players. Organisations for many years have overlooked, misunderstood and to a large degree ignored the contributions of the steady and capable performers, the B players. Understanding the retention needs of B players has become critical in ensuring organisational success in the short and long term. The purpose of the research aimed to identify the key factors influencing the retention of B players across generations and ethnic groups, and thereby develop a retention framework that will contribute towards the improved retention of B players. The study adopted a dual approach, incorporating a qualitative and quantitative methodology. Interviews were conducted with key stakeholders to validate the questionnaire and gain insights regarding the key retention variables that influence B players. A questionnaire was then distributed to respondents to obtain their views. Data was gathered electronically and analysed against the research objectives defined. The key findings indicated that B players are most influenced by Financial Reward&Recognition, Independence&Freedom and Leadership& Management factors. A Factor Significance and Variable Importance Retention Framework was developed to assist organisations to develop dynamic multidimensional strategies. Copyright / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted
65

A socio-historical analysis of education/in the / third world and its implication)lfor rural development

Ernstzen, June January 1993 (has links)
Magister Artium - MA / The greater part of the analysis relates to the needs of the Third World, with an emphasis on Africa (as opposed to the entire Third World). Within the African context, these needs should be seen against a background created by political, economic and demographic changes. Throughout the educational process the concept of education as learning, and not simply as schooling, has had important implications for development, in particular rural development.
66

A Consumer-based Evaluation of a Family Camp

Covey, Christine Davis 17 March 2010 (has links) (PDF)
The purpose of this study was to evaluate a family camp's performance from a consumer (parent) perspective. An Importance-Performance Analysis was used. Responses averages were plotted on a grid of importance versus performance with the overall means used as cross-hairs to create an action grid of four quadrants: keep-up-the-good-work (high importance/high performance), concentrate-here (high importance/low performance), possible-overkill (low importance/high performance), and low-priority (low importance/low performance). Findings indicated that parents are in large part receiving good performance on the factors that are important to them. Findings identified factors that were important to parents including some factors that camp directors were not previously aware of. Three of the five highest importance factor scores were regarding accommodations (clean facility, restrooms provided, and showers provided). All five of the top performance factor scores were regarding programming details. Implications for family camp providers and recommendations for future research are discussed.
67

The Social Importance of a Small-town Theater: A Case Study of the Pulaski Theatre, Pulaski, Virginia

Allen, April Diane 04 May 2004 (has links)
The purpose of this study was to discover the various meanings that the Pulaski Theatre held for the residents of Pulaski and the theatre's social importance to the town. The following research objectives directed this study: 1) to document the theatre's history from the time it was built in 1911 until the present day, 2) to uncover memories or feelings associated with the theatre, and 3) to determine if design features of the theatre building influenced those feelings/memories. In documenting the history of the theatre, design features of the original 1911 building were examined as well as changes over time. To determine if design features of the building influenced the feelings/memories that were associated with the structure it was important first to discover which architectural and design features people remembered, if any, and then to determine if these design features reflected a meaningful association, i.e. sense of place to participants. Also of interest was whether this association or sense of place would be similar or different for all. Participants were fifteen males and females aged 43 to 82 who had attended the theatre over time. All participants grew up in Pulaski and six had lived there their entire lives. Both African Americans and Caucasians participated. Subjects were asked to draw a picture of the theatre that expressed their experience of the space. After the drawing, they were asked to discuss the picture and its meaning to them. Clare Cooper Marcus and others used this environmental autobiography technique as a method to bring a person's experiences of a place to a conscious level. Tape-recorded interviews were conducted and transcribed by the researcher to discover memories of the theatre and the meaning of the theatre to the participants. Data were analyzed by coding to look for emerging themes or categories that relate to the research question. Of interest was whether or not the Pulaski Theatre represented a sense of place to residents and if that sense of place varied for different participants. Document research was conducted through old newspapers and artifacts in the Raymond Ratcliffe Museum (the historic museum in Pulaski), documents from scrapbooks, architectural plans, and the files of the Town of Pulaski. Themes that were identified from the research were (1) the structure was an integral part of the community, (2) the theatre was a reflection of the community's social norms and roles, such as segregation, and (3) the theatre interior contributed to the social atmosphere of the space. The theatre building, while transformed over time, retained a presence in the town and memories associated with it across time were significant in creating a sense of place in the community. The theatre was remembered as a setting that brought excitement and stimulation to children and adults for many years. Participants felt "at home" in the theatre, having favored sections of the theatre where they routinely sat. School children attending the weekly matinees in the summer and African Americans sitting in their special section of the balcony developed a special identity with that particular space within the theatre. Even after segregation, many African Americans continued to sit in the balcony where they had sat for many years and felt at home. The unique characteristics of these spaces were dependent on the people that frequented them rather than the architecture of the building. The sense of place was one of personal relationships and emotional attachments rather than of bricks and mortar. Memories of the theatre were stories of groups or individuals and their interactions in the space. The building represented these individuals and what they brought to this place and time. The Pulaski Theatre played a great role in interactions with friends and neighbors and was significant in reflecting a sense of place in this community. / Ph. D.
68

Interpreting Random Forest Classification Models Using a Feature Contribution Method

Palczewska, Anna Maria, Palczewski, J., Marchese-Robinson, R.M., Neagu, Daniel 18 February 2014 (has links)
No / Model interpretation is one of the key aspects of the model evaluation process. The explanation of the relationship between model variables and outputs is relatively easy for statistical models, such as linear regressions, thanks to the availability of model parameters and their statistical significance . For “black box” models, such as random forest, this information is hidden inside the model structure. This work presents an approach for computing feature contributions for random forest classification models. It allows for the determination of the influence of each variable on the model prediction for an individual instance. By analysing feature contributions for a training dataset, the most significant variables can be determined and their typical contribution towards predictions made for individual classes, i.e., class-specific feature contribution “patterns”, are discovered. These patterns represent a standard behaviour of the model and allow for an additional assessment of the model reliability for new data. Interpretation of feature contributions for two UCI benchmark datasets shows the potential of the proposed methodology. The robustness of results is demonstrated through an extensive analysis of feature contributions calculated for a large number of generated random forest models.
69

A PROBABILISITIC BASED FAILURE MODEL FOR COMPONENTS FABRICATED FROM ANISOTROPIC GRAPHITE

Xiao, Chengfeng 20 May 2014 (has links)
No description available.
70

The Effect of Goal Importance on Counterfactual Activation

Walker, Ryan J. January 2018 (has links)
No description available.

Page generated in 0.0637 seconds