|
|
|
Registros recuperados: 16 | |
|
| |
|
| |
|
| |
|
| |
|
| |
|
|
Schiefer, Jan; Hartmann, Monika. |
This paper analyzes the variance in accounting profitability within the European food industry. Based on a large panel data set, the variance in return on assets (ROA) is decomposed into year, country, industry, and firm effects. Further on, we include all possible interactions between year, country, and industry and discuss the theoretical foundations for these effects. After singling out the significant effect classes in a nested ANOVA with a thoroughly designed rotation regarding the order of effect introduction, we determine effect magnitude using components of variance (COV). Our results show that firm characteristics seem to be far more important than industry structure in determining the level of economic return within the food industry. Year and... |
Tipo: Conference Paper or Presentation |
Palavras-chave: Variance components; Abnormal profit; EU-27; MBV; RBV; Comparative advantage; Agribusiness; Agricultural Finance; Financial Economics; Industrial Organization; Marketing. |
Ano: 2009 |
URL: http://purl.umn.edu/49322 |
| |
|
| |
|
|
Kibala,L; Rozempolska-Rucinska,I; Kasperek,K; Zieba,G; Lukaszewicz,M. |
ABSTRACT The study aimed at investigating which of four traits is the most representative of eggshell strength (destructive eggshell thickness measurement, eggshell weight, egg specific gravity, ultrasonic measurement of eggshell thickness) and could be used for selection purposes. To date, investigations focused mostly on pairwise (eggshell strength vs. another eggshell feature) analyses, resulting in two-, maybe three-trait, models when eggshell traits are considered. Since the covariance estimates are also model dependent, we collected five eggshell traits within one analysis, which better reflects what occurs in nature. The eggs were collected from 4571 Rhode Island White and 2426 Rhode Island Red hens. A multiple-trait animal model and the REML method... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Variance components; Selection criterion; Trait choice.. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2018000100099 |
| |
|
|
Dornelles,Mariana de Almeida; Araújo,Ronyere Olegário de; Everling,Dionéia Magda; Weber,Tomás; Lopes,Jader Silva; Pacheco,Paulo Santana; Breda,Fernanda Cristina; Rorato,Paulo Roberto Nogara. |
The objective of this research was to compare the magnitude of genetic parameters (coefficients of heritability and genetic correlation) as estimated by the Restricted Maximum Likelihood (REML) method and Bayesian Inference, and to estimate the genetic and phenotypic trends to the traits height at the withers (HW24) and weight at 24 months of age (W24). The average heritability estimated by Bayesian Inference to HW24 was 0.47, and it was lower than that obtained by REML bi-trait analysis (0.52); however, the value estimated to W24 (0.39) was higher than that obtained by REML bi-trait analysis (0.38). The genetic correlation estimate between W24 and HW24 traits obtained by the REML method (0.66) was lower than that obtained by the Bayesian Inference Method... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Genetic correlation; Genetic progress; Variance components. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012000600015 |
| |
|
|
Carneiro Júnior, José Marques; Embrapa Acre; Assis, Giselle Mariano Lessa de; Embrapa Acre; Euclydes, Ricardo Frederico; Universidade Federal de Viçosa; Martins, Williane Maria de Oliveira; Embrapa Acre; Wolter, Priscila Ferreira; Embrapa Acre. |
Dados simulados foram utilizados para comparar as metodologias Eblup e Bayesiana, em dados com homogeneidade de variâncias, heterogeneidade de variância genética e heterogeneidade de variância genética e ambiental. Para obtenção dessas estruturas foram feitos descartes estratégicos dos valores genéticos aditivos e ambientais de acordo com o tipo de heterogeneidade e o nível de variabilidade desejada (alta, média ou baixa), sendo utilizados dois tamanhos de população (grande e pequena). Para a metodologia Bayesiana foram utilizados três níveis de informação a priori: não informativo, pouco informativo e informativo. A presença da heterogeneidade de variâncias causa problemas para a seleção dos melhores indivíduos, principalmente se a heterogeneidade estiver... |
Tipo: Simulação de dados |
Palavras-chave: 5.04.02.00-5 heterogeneidade de variâncias; Componentes de variância; Simulação; Informação a priori Genética e Melhoramento dos Animais Domésticos heterogeneity of variance; Variance components; Simulation; Priori information. |
Ano: 2010 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/7862 |
| |
|
|
Falcão, Alencariano José da Silva; UFT; Martins, Elias Nunes; UEM; Costa, Cláudio Napolis; EMBRAPA; Mazucheli, Josmar; UEM. |
Os efeitos, sobre a avaliação genética da interação reprodutor-região, foram investigados analisando-se 108.702 registros de produção de leite (PL305) de vacas da raça Holandesa, pertencentes a rebanhos de Minas Gerais, São Paulo, Paraná, Sanata Catarina e Rio Grande do Sul. Um modelo animal multicarácter foi aplicado para estimar os componentes de variância e covariância utilizando amostragem de Gibbs. As médias a posteriori da variância genética de Santa Catarina e Rio Grande do Sul foram superiores (p < 0,001) às estimadas nos demais estados e iguais (p > 0,05) entre si. As herdabilidades variaram entre 0,24 e 0,38. As correlações genéticas entre os estados foram de baixa magnitude e variaram entre 0,07 a 0,33. Os valores de correlação de Spearman... |
|
Palavras-chave: 5.05.04.00-2 Reprodução Animal cadeia de Markov; Correlação; Componentes de variância; Herdabilidade. Markov chain; Correlation; Variance components; Heritability. |
Ano: 2008 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/4706 |
| |
|
|
Bresolin, Tiago; Everling, Dionéia Magda; Rorato, Paulo Roberto Nogara; Braz, Camila Urbano; Breda, Fernanda Cristina. |
The aim of this study was to assess the occurrence of genotype-environment interaction, as well as its effects on the magnitude of genetic parameters and the classification of Nellore breeding bulls for the trait adjusted weight at 205 days (W205) on Southern Brazil. The components of (co)variance were estimated by Bayesian inference, using a linear-linear animal model in a bi-trait analysis. The proposed model for the analyses considers as random the direct additive genetic and maternal effects and residual effects, and as fixed effects the contemporary groups, sex, season of birth and weighing, and calving age as covariable (linear and quadratic effects). The a posteriori mean estimates of the direct heritabilities for W205 in the three States varied... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Beef cattle; Variance components; Genetic correlation; Bayesian inference; Genetic parameters.. |
Ano: 2015 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAnimSci/article/view/23602 |
| |
|
| |
|
| |
|
| |
|
|
Ribeiro,Jeferson Corrêa; Silva,Luciano Pinheiro da; Soares,Aline Camporez Crispim; Caetano,Giovani da Costa; Leite,Carla Daniela Suguimoto; Bonafé,Cristina Moreira; Sousa,Mariele Freitas; Torres,Robledo de Almeida. |
ABSTRACT: We estimated genetic and phenotypic parameters for egg production in meat-type quails aiming to propose an optimal age for selection through partial record egg production. Data of 3,503 female quails from two strains (namely, UFV1, with 1,811 and UFV2 with 1,692 females) were used. Egg production was assessed by the number of eggs recorded after 42 days of age and each partial period consisted on 35 days of egg production forward. Covariance components were estimated by using single and bivariate animal model, comprising each partial period of egg production and full egg production period (one year of egg laying). Regarding strain UFV1, heritability estimates ranges from 0.03 to 0.16, and for strain UFV2 0.20 to 0.25. The highest genetic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coturnix coturnix; Genetic correlation; Genetic evaluation; Heritability; Variance components. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782017000400653 |
| |
Registros recuperados: 16 | |
|
|
|