DNase
Elisa assay of DNase
The DNase
data frame has 176 rows and 3 columns of data obtained during development of an ELISA assay for the recombinant protein DNase in rat serum.
Usage
DNase
Format
An object of class c("nfnGroupedData", "nfGroupedData", "groupedData", "data.frame")
containing the following columns:
- Run
-
an ordered factor with levels
10
< ... <3
indicating the assay run. - conc
-
a numeric vector giving the known concentration of the protein.
- density
-
a numeric vector giving the measured optical density (dimensionless) in the assay. Duplicate optical density measurements were obtained.
Details
This dataset was originally part of package nlme
, and that has methods (including for [
, as.data.frame
, plot
and print
) for its grouped-data classes.
Source
Davidian, M. and Giltinan, D. M. (1995) Nonlinear Models for Repeated Measurement Data, Chapman & Hall (section 5.2.4, p. 134)
Pinheiro, J. C. and Bates, D. M. (2000) Mixed-effects Models in S and S-PLUS, Springer.
Examples
require(stats); require(graphics) coplot(density ~ conc | Run, data = DNase, show.given = FALSE, type = "b") coplot(density ~ log(conc) | Run, data = DNase, show.given = FALSE, type = "b") ## fit a representative run fm1 <- nls(density ~ SSlogis( log(conc), Asym, xmid, scal ), data = DNase, subset = Run == 1) ## compare with a four-parameter logistic fm2 <- nls(density ~ SSfpl( log(conc), A, B, xmid, scal ), data = DNase, subset = Run == 1) summary(fm2) anova(fm1, fm2)