lip {gamlss.cens}R Documentation

Date for lip

Description

The data set used in this section was given by Dr Peggy Braun (University of Leipzig) passed on by the project co-ordinator Dr Jane Sutherland of London Metropolitan University.

It consists of experimental results concerned with enzymology from a research project which attempted to develop a generic food spoilage model.

The data set contains a column called NAMES, which shows the experiment name, three columns with values of the environmental conditions: temperature (Tem), pH and water activity (aw), and the rest of the columns containing the activity of the cocktails, observed at certain days.

The researchers recorded the activity of proteases and lipases in each cocktail and were interested in predicting the time when the activity started given some environmental conditions. The activity is a positive integer and enzymes are considered inactive when activity=0.

Usage

data(lip)

Format

A data frame with 120 observations on the following 14 variables.

name
a factor with levels the different experiment
Tem
a numeric vector showing the temperature
pH
a numeric vector PH
aw
a numeric vector water activity
X0.d
a numeric vector if enzyme reacted at days 0-1
X1.d
a numeric vector
X2.d
a numeric vector
X4.d
a numeric vector
X11.d
a numeric vector
X18d.
a numeric vector
X25.d
a numeric vector
X32.d
a numeric vector
X39.d
a numeric vector
y
a matrix with 3 columns: this is a Surv() object indicating the start the finish and censored indicator as defined in function Surv()

Details

Source

Prof Jane Sutherland

References

Examples

data(lip)
## maybe str(lip) ; plot(lip) ...

[Package gamlss.cens version 1.7.0 Index]