quantchem (version 0.12-1)

anova.lmcal, anova.nlscal: ANOVA tests for calibration models

Description

This function performs ANOVA tests between fitted calibration models.

Usage

anova.lmcal(object, ...)
anova.nlscal(object, ...)

Arguments

object

an object of class 'lmcal' or 'nlscal'

...

additional arguments (ignored)

Value

• A list of 'anova' objects:
• mandel
  The test between linear and quadratic fit
• logmandel
  The same test, between two log-log models
• table
  The test between linear, quadratic, cubical and 4th order models without weighting
• wtable
  The test between linear, quadratic, cubical and 4th order models with weighting

Details

For 'lmcal' models this function performs four tests: two ANOVAs between linear and quadratic model, without and with log-log transform (first is mentioned in literature as Mandel's fitting test), and two ANOVAs comparing four polynomial models, weighted and unweighted. For 'nlscal' models two ANOVAs are performed - between asymptotic models without and with intercept term, and between three and four parameter logistic models.

See Also

lmcal, nlscal

Examples

data(nitrate)
attach(nitrate)
fit = lmcal(conc,area)
anova(fit)
fit2 = nlscal(conc,area)
anova(fit2)