Home           Contact us           FAQs           
     Journal Home     |     Aim & Scope    |    Author(s) Information      |     Editorial Board     |     MSP Download Statistics
2013 (Vol. 5, Issue: 04)
Article Information:

Fitting Logistic Growth Curve with Nonlinear Mixed-effects Models

Yaoxiang Li and Lichun Jiang
Corresponding Author:  Lichun Jiang 

Key words:  Diameter growth, logistic function, model calibration, nonlinear mixed-effects modeling, , ,
Vol. 5 , (04): 392-397
Submitted Accepted Published
October 31, 2012 December 22, 2012 April 15, 2013

A nonlinear mixed-effects modeling approach was used to model individual tree diameter increment based on Logistic growth function for dahurian larch (Larix gmelinii Rupr.) plantations in northeastern China. The study involved the estimation of fixed and random parameters, as well as procedures for determining random effects variance-covariance matrices. Results showed that the mixed-effects model provided better model fitting than the fixed-effects model. The logistic model with three random parameters b1, b2, b3 was considered the best mixed model. Time series correlation structures included Autoregressive correlation structure AR (1) and AR (2), Moving Average correlation structure MA (1) and MA (2) and Autoregressive-Moving Average correlation structure [ARMA (1, 1)] and ARMA (2, 2) were incorporated into the best mixed model. The mixed model with MA (2) correlation structure showed lower AIC and BIC values and significantly improved model performance (LRT = 545.6, p<0.0001). Techniques for calibrating the diameter growth model for a particular tree of interest were also explored. The results indicated that the mixed-effects model provided better diameter predictions than the models using only fixed-effects parameters.
Abstract PDF HTML
  Cite this Reference:
Yaoxiang Li and Lichun Jiang, 2013. Fitting Logistic Growth Curve with Nonlinear Mixed-effects Models.  Advance Journal of Food Science and Technology, 5(04): 392-397.
    Advertise with us
ISSN (Online):  2042-4876
ISSN (Print):   2042-4868
Submit Manuscript
   Current Information
   Sales & Services
Home  |  Contact us  |  About us  |  Privacy Policy
Copyright © 2015. MAXWELL Scientific Publication Corp., All rights reserved