growth.curve {agce}R Documentation

Perform an anova on slopes.

Description

This function is particular a case of the manova.growth, the manova reduces to an ANOVA when the a particular growth curve is linear.

Usage

growth.curve(data, C=NULL, U=NULL, normal=TRUE, B=1000, time=NULL)

Arguments

data The data matrix or data frame, where the first column correspond to the group ids, the second to the animal ids, the remaining columns are the measurements at each time.
C The left contrast matrix. Default to test same rate of growth in each group.
U The right contrast matrix. Default to test same rate of growth in each group.
normal A logical value, if normal is true the standard deviations of the rates are computed based on normal assumption of the measurements, otherwise computed by bootstraping. Default to TRUE.
B A numeric value, the number of bootstraps. Only used if normal is FALSE.
time A vector of numeric values corresponding to the time points at which the measurements were effectued. Time is absolutely required.

Details

In this function, we assume that the mean is of the form A+B*t. Where A, B are estimated . Therefore the mean is just a function (matrix multiplication ) of the rates.

Value

Ftest The value of the F-test used to test the hypothesis based on C and U.
df1 The numerator degrees of freedom for the F-test
df2 The denominator degrees of freedom for the F-test
p The p-value associated to the F-test
mean The estimate of the mean
std.mean The standard deviation associated to the mean
rate The rate of growth. Set to NULL if rate is FALSE
std.rate The standard deviation of the rates. Set to NULL if rate is FALSE

Author(s)

Raphael Gottardo

References

Daniel F. Heitjan, Andrea Manni and Richard J. Santen Statistical Analysis of in Vivo Tumor Growth Experiments Cancer Research 53:6042-6050, 1993.

See Also

manova.growth

Examples

data(Bt20)
growth.curve(Bt20, C=NULL, U=NULL, normal=TRUE, time=c(0,3,7,10,14,16))

[Package agce version 1.2 Index]