Computer construction of experimental plans

Experimental plans identify the treatment allocated to each unit and they are necessary for the supervision of most comparative experiments. Few computer programs have been written for constructing experimental plans but many for analysing data arising from designed experiments. In this thesis the construction of experimental plans is reviewed so as to determine requirements for a computer program. One program, DSIGNX, is described. Four main steps in the construction are identified: declaration, formation of the unrandomized plan (the design), randomization and output. The formation of the design is given most attention. The designs considered are those found to be important in agricultural experimentation and a basic objective is set that the 'proposed' program should construct most designs presented in standard texts (e.g. Cochran and Cox (1957)) together with important designs which have been developed recently. Topics discussed include block designs, factorial designs, orthogonal Latin squares and designs for experiments with non-independent observations. Some topics are discussed in extra detail; these include forming standard designs and selecting defining contrasts in symmetric factorial experiments, general procedures for orthogonal Latin squares and constructing serially balanced designs. Emphasis is placed on design generators, especially the design key and generalized cyclic generators, because of their versatility. These generators are shown to provide solutions to most balanced and partially balanced incomplete block designs and to provide efficient block designs and row and column designs. They are seen to be of fundamental importance in constructing factorial designs. Other versatile generators are described but no attempt is made to include all construction techniques. Methods for deriving one design from another or for combining two or more designs are shown to extend the usefulness of the generators. Optimal design procedures and the evaluation of designs are briefly discussed. Methods of randomization are described including automatic procedures based on defined block structures and some forms of restricted randomization for the levels of specified factors. Many procedures presented in the thesis have been included in a computer program DSIGNX. The facilities provided by the program and the language are described and illustrated by practical examples. Finally, the structure of the program and its method of working are described and simplified versions of the principal algorithms presented

Planos em blocos incompletos equilibrados e aplicações na educação

Neste trabalho, começamos por abordar o Delineamento experimental, que pode ser visto como parte do processo científico. Ainda trataremos da importância das técnicas avançadas do Planeamento de Experiências, a utilização de Blocos com o intuito de redução da variabilidade que é introduzida pelos tratamentos, explorando ainda algumas das metodologias e respetivas componentes de computação. No seguimento do desenvolvimento da dissertação destaca-se uma abordagem essencialmente teórica dos BIBD, sendo posteriormente apresentadas definições e abordadas questões de existência dos mesmos, evidenciando-se uma primeira abordagem aos vários modelos BIBD. Também focaremos dentro da Análise Estatística dos BIBD, a construção da tabela Anova com a análise intrabloco e interbloco para os BIBD. Iremos igualmente rever os métodos de construção dos BIBD, fazendo a apresentação de alguns exemplos práticos da sua construção e algoritmos; bem como, a importância da utilização do software R. Para a análise dos dados do nosso questionário foi utilizado o software R, versão 2.12.2. Por fim, iremos testar uma aplicação prática dos BIBD na Área da Educação. Neste exemplo prático procurarei aferir o grau de preparação dos alunos em final de ciclo (9º ano de escolaridade) na disciplina de Matemática, dentro das Metas Curriculares de Final de 3ª Ciclo. Constatamos que existiam diferenças ao nível de significância entre alguns dos domínios testados, por exemplo, entre os domínios dos Números e Cálculo e a Geometria.This work presents the results of the study and of the research of the Balanced Incomplete Block Designs (BIBD) and also Balanced Incomplete Block Designs with Repetition (BIBDR), being applied in a practical case, in the analysis to a questionnaire carried out in six Schools of the 3rd cycle of Portugal. We start by addressing the experimental design, which can be seen as part of the scientific process. We will also discuss the importance of Advanced Experimental Design techniques, the use of Blocks in order to reduce the variability that is introduced by the treatments, and explore some of the methodologies and their computational components. Following the development of the dissertation, an essentially theoretical approach to the BIBD is highlighted, and definitions and questions about the existence of the BIBD are presented, evidencing a first approach to the various BIBD models. We will also focus on Statistical Analysis of BIBD, the Anova on BIBD, construction of Anova table and intrablock and interblock analysis for BIBDs. We will also review the methods of construction of the BIBD, presenting some practical examples of its construction and algorithms; as well as the importance of using the R software. For the analysis of the data of our questionnaire, software R, version 2.12.2 was used. Finally, we will study a practical application of the BIBD in the Education Area. In this practical example, we will try to measure the level of preparation of the students at the end of the cycle (9th year of schooling) in the Mathematics discipline, within the Curricular Goals of the 3rd Cycle End. We found that there were significant differences between some of the domains tested, for example between Numbers and Calculus and Geometry domains at the significance level

Energy: A continuing bibliography with indexes, issue 34

This bibliography lists 1015 reports, articles, and other documents introduced into the NASA scientific and technical information system from April 1, 1981 through June 30, 1981

Aeronautical Engineering: A cumulative index to the 1984 issues of the continuing bibliography

This bibliography is a cumulative index to the abstracts contained in NASA SP-7037(171) through NASA SP-7037(182) of Aeronautical Engineering: A Continuing Bibliography. NASA SP-7037 and its supplements have been compiled through the cooperative efforts of the American Institute of Aeronautics and Astronautics (AIAA) and the National Aeronautics and Space Administration (NASA). This cumulative index includes subject, personal author, corporate source, foreign technology, contract, report number, and accession number indexes

Energy: A continuing bibliography with indexes (Issue 29)

This bibliography lists 1360 reports, articles, and other documents introduced into the NASA scientific and technical information system from January 1, 1981 through March 31, 1981