Nonlinear quantile regression to describe the dry matter accumulation of garlic plants

Autor: Guilherme Alves Puiatti, Paulo Roberto Cecon, Moysés Nascimento, Ana Carolina Campana Nascimento, Antônio Policarpo Souza Carneiro, Fabyano Fonseca e Silva, Mário Puiatti, Cosme Damião Cruz
Jazyk: English<br />Portuguese
Rok vydání: 2020
Předmět:
Zdroj: Ciência Rural, Vol 50, Iss 1 (2020)
Druh dokumentu: article
ISSN: 1678-4596
0103-8478
DOI: 10.1590/0103-8478cr20180385
Popis: ABSTRACT: The objective of this study was to adjust nonlinear quantile regression models for the study of dry matter accumulation in garlic plants over time, and to compare them to models fitted by the ordinary least squares method. The total dry matter of nine garlic accessions belonging to the Vegetable Germplasm Bank of Universidade Federal de Viçosa (BGH/UFV) was measured in four stages (60, 90, 120 and 150 days after planting), and those values were used for the nonlinear regression models fitting. For each accession, there was an adjustment of one model of quantile regression (τ=0.5) and one based on the least squares method. The nonlinear regression model fitted was the Logistic. The Akaike Information Criterion was used to evaluate the goodness of fit of the models. Accessions were grouped using the UPGMA algorithm, with the estimates of the parameters with biological interpretation as variables. The nonlinear quantile regression is efficient for the adjustment of models for dry matter accumulation in garlic plants over time. The estimated parameters are more uniform and robust in the presence of asymmetry in the distribution of the data, heterogeneous variances, and outliers.
Databáze: Directory of Open Access Journals