Misra1a: Monomolecular Absorption Data

In NISTnls: Nonlinear least squares examples from NIST

Description

The Misra1a data frame has 14 rows and 2 columns.

Format

This data frame contains the following columns:

y

A numeric vector of volume values.

x

A numeric vector of pressure values.

Details

These data are the result of a NIST study regarding dental research in monomolecular adsorption. The response variable is volume, and the predictor variable is pressure.

Source

Misra, D., NIST (1978). Dental Research Monomolecular Adsorption Study.

Examples

Try <- function(expr) if (!inherits(val <- try(expr), "try-error")) val
plot(y ~ x, data = Misra1a)
Try(fm1 <- nls(y ~ b1*(1-exp(-b2*x)), data = Misra1a, trace = TRUE,
           start = c(b1 = 500, b2 = 0.0001) ))
Try(fm1a <- nls(y ~ b1*(1-exp(-b2*x)), data = Misra1a, trace = TRUE,
           alg = "port", start = c(b1 = 500, b2 = 0.0001) ))
Try(fm2 <- nls(y ~ b1*(1-exp(-b2*x)), data = Misra1a, trace = TRUE,
           start = c(b1 = 250, b2 = 0.0005) ))
Try(fm2a <- nls(y ~ b1*(1-exp(-b2*x)), data = Misra1a, trace = TRUE,
           alg = "port", start = c(b1 = 250, b2 = 0.0005) ))
Try(fm3 <- nls(y ~ 1-exp(-b2*x), data = Misra1a, trace = TRUE,
           start = c(b2 = 0.0001), algorithm = "plinear" ))
Try(fm4 <- nls(y ~ 1-exp(-b2*x), data = Misra1a, trace = TRUE,
           start = c(b2 = 0.0005), algorithm = "plinear" ))

## Using a self-starting model
Try(fm5 <- nls(y ~ SSasympOrig(x, Asym, lrc), data = Misra1a))

NISTnls documentation built on May 2, 2019, 2:37 a.m.