An Overview of Planning Experiments for Reliability Data
Speaker: Geoff Vining
Authors: Geoff Vining (Virginia Tech)
Abstract: The traditional approaches for the statistical design and analysis of experiments assume roughly normal distributions for the response (dependent variable). Reliability analyses, however, involve highly skewed and censored (the test stops before the process is complete) data, often modeled by distributions such as the Weibull. On the other hand, most reliability practitioners have little or no training in the statistical planning of experiments. These practitioners often have no basic understanding of such fundamental concepts as blocking, sub-sampling, and mixed models. As a result, the two communities would benefit from more cross-fertilization. This talk presents a high level overview of the basic differences between the two communities. It then outlines some current and proposed statistical designs and analyses for reliability data.
Designs for selection in early stages of plant breeding
Speaker: Júlio S. de S. Bueno F.
Authors: Júlio S. de S. Bueno Filho (UFLA); Steven G. Gilmour (University of Southampton)
Abstract: In early stages of plant breeding design main restraints are associated with the number of replications (availability of biological material). It is also quite obvious that mixed effects models should be used to the analysis. Moreover, prior knowledge can be useful factor as there is not too much information coming from the actual experiment. However, all of this is ignored in actualresearch from plant breeding (academic research as well as commercial companies). We propose a framework to use prior information and build proper designs given the usual restraints. An example with sugarcane breeding is discussed.
Adaptive Control Chart for Linear Profile Monitoring
Speaker: Maysa S. de Magalhães
Authors: Maysa S. de Magalhães (ENCE/IBGE)1; Viviany L. Fernandes (UERJ); Francisco D. Moura Neto (UERJ)
Abstract: In some production processes the quality characteristics can be represented by profiles or linear functions. We propose adaptive control charts to monitor the coefficient vector of a simple linear regression model, once fixed parameter control charts are slow in detecting small to moderate shifts in the process parameters, that is, the intercept and the slope. A study on the performance of the proposed control charts was done, considering the average time until a signal.
Demands and paradigms of analysis in the agricultural market
Authors: Guilherme Moraes Ferraudo (Monsanto)
Speaker: Guilherme Moraes Ferraudo
Abstract: Monsanto is present over 60 countries and its history in Brazil begins on 1963 at São Paulo city. Currently, the company works to develop technologies that contribute to ally foods production, fibers and energy with environmental preservation. In Brazil, Monsanto have the following portfolio to deliver its solution to the sustainable agriculture (plant breeding, biotechnology and sustainable agronomic practices): (i) crop protection; (ii) seeds – soybean, corn, cotton, sorghum, vegetables and sugarcane.Next are presented some challenges that we are facing and we believe that the academics could be assisting us with its researches.1. Multivariate quality statistical control. What is the technique more appropriate to assess trials quality when we evaluate genetic materials performance (product development) in field?2. Design and analysis of agronomic systems trials. Agronomic systems trials present complexity to assess the system which is used by grower as a whole, at the same cultivation area: (i) crop; (ii) herbicide; (iii) winter/cover crops; and (iv) agronomic practices. Such peculiarities limit the application of the widely used models (ANOVA and multiple comparisons tests). What is the best way to analyze these peculiarities in long term trials, on that either management or previous crop makes influence on subsequent evaluations?
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