AM: Analysis: Avhad and Marchetti

In AgroReg: Regression Analysis Linear and Nonlinear for Agriculture

Analysis: Avhad and Marchetti

Description

This function performs Avhad and Marchetti regression analysis.

Usage

AM(
  trat,
  resp,
  initial = list(alpha, k, n),
  sample.curve = 1000,
  ylab = "Dependent",
  xlab = "Independent",
  theme = theme_classic(),
  legend.position = "top",
  error = "SE",
  r2 = "all",
  point = "all",
  width.bar = NA,
  scale = "none",
  textsize = 12,
  pointsize = 4.5,
  linesize = 0.8,
  linetype = 1,
  pointshape = 21,
  fillshape = "gray",
  colorline = "black",
  round = NA,
  xname.formula = "x",
  yname.formula = "y",
  comment = NA,
  fontfamily = "sans"
)

Arguments

trat	Numeric vector with dependent variable.
resp	Numeric vector with independent variable.
initial	Starting estimates
sample.curve	Provide the number of observations to simulate curvature (default is 1000)
ylab	Variable response name (Accepts the expression() function)
xlab	treatments name (Accepts the expression() function)
theme	ggplot2 theme (default is theme_bw())
legend.position	legend position (default is "top")
error	Error bar (It can be SE - default, SD or FALSE)
r2	coefficient of determination of the mean or all values (default is all)
point	defines whether you want to plot all points ("all") or only the mean ("mean")
width.bar	Bar width
scale	Sets x scale (default is none, can be "log")
textsize	Font size
pointsize	shape size
linesize	line size
linetype	line type
pointshape	format point (default is 21)
fillshape	Fill shape
colorline	Color lines
round	round equation
xname.formula	Name of x in the equation
yname.formula	Name of y in the equation
comment	Add text after equation
fontfamily	Font family

Details

The Avhad e Marchetti model is defined by:

y = \alpha \times e^{kx^n}

Value

The function returns a list containing the coefficients and their respective values of p; statistical parameters such as AIC, BIC, pseudo-R2, RMSE (root mean square error); largest and smallest estimated value and the graph using ggplot2 with the equation automatically.

Author(s)

Gabriel Danilo Shimizu

Leandro Simoes Azeredo Goncalves

References

Seber, G. A. F. and Wild, C. J (1989) Nonlinear Regression, New York: Wiley & Sons (p. 330).

Avhad, M. R., & Marchetti, J. M. (2016). Mathematical modelling of the drying kinetics of Hass avocado seeds. Industrial Crops and Products, 91, 76-87.

Examples

library(AgroReg)
data("granada")
attach(granada)
AM(time,100-WL,initial=list(alpha = 610.9129, k=-1.1810, n=0.1289 ))

AgroReg documentation built on May 29, 2024, 9:13 a.m.