ENBIS: European Network for Business and Industrial Statistics
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ENBIS Spring Meeting 2018
4 – 6 June 2018; Florence, Italy Abstract submission: 17 November 2017 – 20 April 2018The following abstracts have been accepted for this event:
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Definitive Augmentation of Definitive Screening Designs
Authors: Phil Kay (SAS)
Primary area of focus / application: Design and analysis of experiments
Keywords: Design of Experiments, Screening, Augment, Response Surface, Definitive Screening Design
Submitted at 5-Feb-2018 13:42 by Phil Kay
Accepted
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Statistical monitoring of nonlinear profiles using mixed effects models
Authors: Arda Vanli (Florida State University, Department of Industrial and Manufacturing Engineering)
Primary area of focus / application: Process
Keywords: Profile monitoring,, statistical process control,, mixed effect models,, functional data
Submitted at 15-Feb-2018 23:44 by Arda Vanli
Accepted
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Optimal target allocation for hypothesis testing in multiarm clinical trials
Authors: Marco Novelli (University of Bologna)
Primary area of focus / application: Design and analysis of experiments
Keywords: Asymptotic inference;, Ethics;, Power;, Response-adaptive designs;, Wald test
Submitted at 24-Feb-2018 17:22 by Marco Novelli
Accepted
Taking into account the problem of testing statistical hypothesis about the equality of the treatment effects, balance is still optimal in the case of two treatments, since it maximizes the power of the test for normal homoscedastic responses and it is asymptotically optimal in the case of binary outcomes (see e.g. Azriel, Mandel and Rinott, 2012; Baldi Antognini 2008). However, in the case of several treatments the balanced allocation may not be efficient, since it is significantly different from the optimal design for hypothesis testing and could be strongly inappropriate for phase III-trials, in which the ethical demand of individual care often induces to skew the allocations to more efficacious (or less toxic) treatments. To derive a suitable compromise between these goals, Baldi Antognini, Novelli and Zagoraiou suggested a constrained optimal target that maximizes the power of the classical Wald test of homogeneity, subject to an ethical constraint on the allocation proportions reflecting the efficacy of the treatments. The aim of the present work is to push forward these results, by providing some important properties of this constrained optimal allocation. The comparisons with some targets proposed in the literature show that the constrained optimal allocation has good performance in terms of statistical power, estimation precision and ethical demands and thus it represents a valid compromise between inference and ethical concerns.
References
Azriel, D., Mandel, M., Rinott, Y. (2012). Optimal allocation to maximize power of two-sample tests for binary response. Biometrika 99, 101-113
Baldi Antognini, A. (2008). A theoretical analysis of the power of biased coin designs. Journal of Statistical Planning and Inference 138, 1792-1798
Baldi Antognini, A., Novelli, M., Zagoraiou, M.: Optimal designs for testing hypothesis in multiarm clinical trials. Submitted.
Begg, C.B., Kalish, L.A. (1984). Treatment Allocation for Nonlinear Models in Clinical Trials: The Logistic Model. Biometrics 40, 409--420
Silvey, S.D. (1980). Optimal Designs. Chapman \& Hall, London -
Exploring the Latent Variable Space of a Multiresponse DOE to Optimize Solid Phase Microextraction (SPME): Case study - Quantification of Volatile Fatty Acids in Wines
Authors: Marco P. Seabra dos Reis (Department of Chemical Engineering, University of Coimbra), Ana Cristina Pereira (CIEPQPF, Department of Chemical Engineering, University of Coimbra), João M. Leça (Faculty of Exact Sciences and Engineering, University of Madeira), Pedro M. Rodrigues (Faculty of Exact Sciences and Engineering, University of Madeira), José C. Marques (Faculty of Exact Sciences and Engineering, University of Madeira)
Primary area of focus / application: Design and analysis of experiments
Secondary area of focus / application: Process
Keywords: Design of Experiments;, Definitive Screening Designs;, Latent variable modelling;, Principal Component Analysis;, Analytical Instrumentation;, Wine
Submitted at 25-Feb-2018 21:47 by Marco P. Seabra dos Reis
Accepted
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Choice models with mixtures: an application to a cocktail experiment
Authors: Hajar Hamidouche (KU Leuven), Peter Goos (KU Leuven)
Primary area of focus / application: Design and analysis of experiments
Secondary area of focus / application: Modelling
Keywords: multinomial logit model, mixed logit model, latent class model, Scheffé model, forces, hierarchical Bayes estimates, Firth estimates
Submitted at 27-Feb-2018 14:40 by Hajar Hamidouche
Accepted
products, and, eventually, offers opportunities for competitive advantage. The literature about choice models is very extensive. However, in the analysis of choice data, products that are mixtures of ingredients have been largely overlooked. This is surprising as a great share of products, such as shampoos, cakes and cocktails, actually are mixtures. The literature on the modeling of data from traditional mixture experiments is also substantial. In this paper, we combine the theory about choice models and traditional mixture models. We will apply the resulting model to data from a real-life
experiment in which consumers made pair-wise comparisons between seven cocktails. More specifically, we will incorporate the Scheffé model, one of the most commonly used mixture models, in three choice models. For the choice models, we will first assume consumer homogeneity. Next, we will allow for heterogeneity among individuals. Therefore, we will discuss the multinomial logit model, the mixed logit model and the latent class model. For identifying segments, besides the latent class model, we will explore a two-stage approach in which subject gradients, Hierarchical Bayes estimates and Firth individual-level estimates are used as input for a cluster analysis. -
Ban of castration and "boar taint" – does it matter?
Authors: Froydis Bjerke (Animalia Meat and Poultry Research Centre)
Primary area of focus / application: Design and analysis of experiments
Secondary area of focus / application: Other: Food and agriculture
Keywords: boar taint, castration, meat quality, FF-Manova, Multivariate Methods, Explorative data analysis
Submitted at 28-Feb-2018 15:51 by Froydis Bjerke
Accepted
Research on boar taint and alternatives to surgical castration has been a large issue in European animal and food research for around twenty years, increasing after the pronounced ban. Alternatives include breeding to reduce boar taint in entire males, online sorting of tainted carcasses on the slaughter line, and immunocastration (injections). Since 2016, Animalia has managed a Norwegian research project "Boars to the market – solutions for Production, Pork quality & Markers for boar taint". The main objective of this project is to initiate economically sustainable alternatives to surgical castration of male pigs. In order to achieve the main objective the following sub-goals are specified:
1. Develop a new on-line measurement method of boar taint.
2. Characterise quality and yield of immunologically castrated pig carcasses.
3. Characterise consumer attitudes to and acceptance of meat from immunologically castrated pigs.
4. Investigate DNA variation for boar taint and implement genomic breeding values.
The presentation considers sub-goal 2 and how experiments and statistics are applied to investigate and quantify differences between the groups of slaughter pigs, mainly from the viewpoint of the meat industry. The analyses are quite explorative, supported by multivariate methods like Partial Least Squares and 50-50 Manova, revealing some of the challenges of measuring boar taint, and carcass and meat quality. Which traits separate the groups, and which do not?
Some references
De Briyne et al. Porcine Health Management (2016) 2:29 DOI 10.1186/s40813-016-0046-x
Langsrud, Ø. (2002), 50-50 Multivariate Analysis of Variance for Collinear Responses, The Statistician, 51, 305-317.
IPEMA, Innovative Approaches for Pork Production with Entire Males - a COST action (CA 15215) supported by the European Union. http://www.ca-ipema.eu/
The project is financially supported from the "BIONÆR" programme of the Research Council of Norway.