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  • 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.
41

A power study of multiple range and multiple F tests

Wine, R. Lowell 12 January 2010 (has links)
In the study of multiple comparisons tests the following topics were discussed: (i) extension to the general case of certain properties and results which previously had been given for three and four means only, (ii) power vectors and average power, (iii) expressions of power for the multiple range tests and for the multiple F test involving only three means, and (iv) methods for evaluating power. These four topics are amplified in order in the four paragraphs below. A set of recursion formulas was obtained for enumerating the decision patterns for n means. x<sub>i</sub> was given by the equation See: Equation where i = 1, 2,...,n-1. In IV, formulas were derived which express d<sub>j,i+1</sub> as a function of the x<sub>i</sub>. This made possible the writing of the bounding equations for any decision region involving n means. The regions (1,2), (1,2,3), (1,2,4), ..., (1,2....,n) for the multiple range tests were described in the sample-space of differences among n means. / Ph. D.
42

Small Grain Variety Comparisons, The University of Arizona Mesa Experiment Farm, 1983

Thompson, R. K., Bobula, J. L. 09 1900 (has links)
No description available.
43

Small Grain Variety Yield Comparisons, Pinal County

Harper, John, Parsons, David K. 09 1900 (has links)
No description available.
44

Small Grains Variety Comparisons at the Yuma Valley Agricultural Experiment Station

Jackson, E. B., Carasso, F. M., Johannsen, J. E. 09 1900 (has links)
No description available.
45

Winter Forage Comparison

Tickes, Barry 09 1900 (has links)
No description available.
46

Social identity and the environment : the influence of group processes on environmentally sustainable behaviour

Duke, Christopher Chandler January 2010 (has links)
The state of the natural environment is a topic of increasing concern, with climate change, loss of biodiversity, and diminishing natural resources all posing eminent threats to the well-being of the planet and its inhabitants. Much of this environmental degradation is caused by human behaviour that can be changed. Psychologists have realised their role in understanding and influencing pro-environmental behaviours to help (see Chapter 1). Most psychological research of environmental behaviour has focused on the individual person as the unit of analysis. While this has been helpful, less attention has been given to how group memberships, and the social influences these create, affect environmental behaviour. Because environmental behaviour often occurs within a social context, understanding the social element may be critically important to promoting environmentally sustainable behaviour (see Chapter 2). Using the social identity approach, this research investigates how various aspects of social group membership interact with individual attributes to influence environmental behaviour. Three related strands of research explore this issue (see Chapter 3 for an overview). In Chapter 4, two studies (Studies 1 and 2) examined how group feedback in the form of social comparisons affect individual behaviour. Based on social identity theory, it was predicted that positive social comparisons would lead to more positive behaviour, and less positive comparisons to less positive behaviour, especially among individuals who identified strongly with the target ingroup. Results from both studies found some support for these hypotheses on certain (but not all) behavioural dependent measures, both at the time of manipulation and one week later. This supports the notion that individual social identification strength can moderate behavioural response to group-level feedback on environmental topics. In Chapter 5, Study 3 considered how interaction within groups via discussion might induce group norms about environmental behaviour that over-ride the effects of intergroup comparisons. A design similar to Study 1 was used, with the addition of a small-group discussion following the feedback manipulation. Discussion content was hypothesised to predict environmental behaviour, with the feedback manipulation having less impact than in Study 1. Results found that the more participants discussed environmental behaviours, the more they engaged in them one week later. This effect was independent of pre-existing environmental values, suggesting that the effects of group interaction were not merely a reflection of existing individual orientations. Following the discussion, values were also found to be very strong predictors of behaviour, a result not found in Study 1, suggesting that group interaction not only shapes individual behaviour but also reduces the classic value-action gap. Together, these findings point to the powerful role that intra-group interaction can play in forming norms of environmental behaviour and shaping individual responses. In Chapter 6, two studies (Studies 4 and 5) explored how comparisons within a group over time (i.e., intra-group comparisons) may function differently to comparisons between groups (i.e., inter-group comparisons), which were explored in Chapter 4. Based on the findings in Chapter 4, positive intergroup comparisons were predicted to result in more positive individual intentions, whereas negative intergroup comparisons were expected to result in reduced intentions. With respect to intra-group comparisons, however, the opposite pattern of effects was predicted. The results of Study 4 did not support these hypotheses. However, feedback from participants suggested that the experimental design may have produced reactance. To address this, Study 5 made use of a revised design, and the results of this study indicated support for the hypotheses. Importantly, in addition to negative and positive comparisons having opposing effects depending on whether these were intra- or inter-group, the processes behind these effects also differed. The effects of intra-group comparisons were mediated by shared responsibility whereas the effects of intergroup comparisons were mediated by environmental value centrality. These results are integrated and discussed in Chapter 7. The recurring theme of these results is that group-level feedback can interact with individual-level variables in subtle but powerful ways, leading to differing outcomes of environmental behaviour. These findings highlight the socially imbedded nature of individual environmental actions, and suggest new avenues for theoretical and practical work in the environmental domain. In particular, on the basis of the studies included in this thesis it is recommended that psychologists who are interested in understanding and changing individual environmental behaviour should incorporate an understanding of intra- and inter-group processes into their theorising and future research.
47

Use of a Commercial Visual Programming Language to Simulate, Decommutate, Test and Display a Telemetry Stream

Wells, George, Baroth, Ed 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / The advantages of using visual programming to create, modify, test and display a telemetry stream are presented. The failure to fully deploy the high-gain antenna of the Galileo spacecraft has resulted in a software redesign of the computer systems onboard the spacecraft to support the low-gain antenna mission. Visual programming software is being used to test new algorithms as part of the ground support for the spacecraft Test Bed. It is very important that any new software algorithms be thoroughly tested on the ground before any modifications are made to the spacecraft. The advantage of using a visual programming language (LabVIEW, National Instruments) is that it provides easy visibility into the decommutation process that is being modified by the Galileo programming support team. In addition, utilities were written using visual programming to allow real-time data display and error detection. A data acquisition board is used to clock in the actual synchronous telemetry signal from the Test Bed at rates below 10 kHz. The time to write and modify the code using visual programming is significantly less (by a factor of 4 to 10) than using text-based code. The gains in productivity are attributed to the communication among the customer, developer, and computer that are facilitated by the visual syntax of the language.
48

The Analysis of the Accumulation of Type II Error in Multiple Comparisons for Specified Levels of Power to Violation of Normality with the Dunn-Bonferroni Procedure: a Monte Carlo Study

Powers-Prather, Bonnie Ann 08 1900 (has links)
The study seeks to determine the degree of accumulation of Type II error rates, while violating the assumptions of normality, for different specified levels of power among sample means. The study employs a Monte Carlo simulation procedure with three different specified levels of power, methodologies, and population distributions. On the basis of the comparisons of actual and observed error rates, the following conclusions appear to be appropriate. 1. Under the strict criteria for evaluation of the hypotheses, Type II experimentwise error does accumulate at a rate that the probability of accepting at least one null hypothesis in a family of tests, when in theory all of the alternate hypotheses are true, is high, precluding valid tests at the beginning of the study. 2. The Dunn-Bonferroni procedure of setting the critical value based on the beta value per contrast did not significantly reduce the probability of committing a Type II error in a family of tests. 3. The use of an adequate sample size and orthogonal contrasts, or limiting the number of pairwise comparisons to the number of means, is the best method to control for the accumulation of Type II errors. 4. The accumulation of Type II error is irrespective of distributions.
49

Sequential multiple comparison testing for budget-limited applications

Gonen, Ofer 12 1900 (has links)
Approved for public release; distribution in unlimited. / Computer simulations which forecast the performance of complicated systems are used as decision aids in many applications. For example, a ship's defensive system may use simulation to support an automated real-time response to a perceived threat, such as an incoming missile. The system uses cumulative simulation data to evaluate a set of options in order to choose the best countermeasure. Since everything happens in "real time", the system has limited time to run the simulation. Normally, a system would run the simulation an equal number of times for each option before coming to a decision. But this may cause the system to waste time on options which can be deemed non-optimal after only a few simulation runs. This time can be better used to help adjudicate between the better options. We evaluate the performance of sequential multiple comparisons algorithms to eliminate inferior options as quickly as possible, in order to have more time to dedicate to the exploration of better options, so that better decisions may be made. These algorithms allow inferior options to be dropped quickly depending on how well separated they are from others, but the algorithms differ in how well they achieve this objective. / Major, Israeli Air Force
50

Economic Comparison of Selected Processing Alternatives for Alfalfa

Bates, Dan J. 01 May 1992 (has links)
Processing alfalfa for export is of significant interest to areas like Millard County, the largest hay-producing county in Utah. In the past year there have ix been significant reductions in the price of hay as a result of increased supplies in the central and western United States. This thesis analyzes the benefits and costs of processing alfalfa into cubes and recompressed bales in order to enter the export market. Costs of production were estimated through the use of enterprise budgets first for the farmer to establish the costs and returns for raising the hay, and secondly for cubing and recompressing the alfalfa at different levels of production and different prices based on those levels of production. The cash flows from these different enterprises were then analyzed using benefit cost ratios, net benefit investment ratios, and internal rates of return. The general conclusion reached is that it is feasible to process alfalfa for export. Profits are sensitive to the price spread between raw and finished products more so than to production efficiencies.

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