NOSTASOT {CorrBin}  R Documentation 
Finding the NOSTASOT dose
Description
The NOSTASOT dose is the NoStatisticalSignificanceOfTrend dose – the largest dose at which no trend in the rate of response has been observed. It is often used to determine a safe dosage level for a potentially toxic compound.
Usage
NOSTASOT(
cbdata,
test = c("RS", "GEE", "GEEtrend", "GEEall", "SO"),
exact = test == "SO",
R = 100,
sig.level = 0.05,
control = soControl()
)
Arguments
cbdata 
a 
test 
character string defining the desired test statistic. See

exact 
logical, should an exact permutation test be performed. See

R 
integer, number of permutations for the exact test 
sig.level 
numeric between 0 and 1, significance level of the test 
control 
an optional list of control settings for the stochastic order
("SO") test, usually a call to 
Details
A series of hypotheses about the presence of an increasing trend overall,
with all but the last group, all but the last two groups, etc. are tested.
Since this set of hypotheses forms a closed family, one can test these
hypotheses in a stepdown manner with the same sig.level
type I error
rate at each step and still control the familywise error rate.
The NOSTASOT dose is the largest dose at which the trend is not statistically significant. If the trend test is not significant with all the groups included, the largest dose is the NOSTASOT dose. If the testing sequence goes down all the way to two groups, and a significant trend is still detected, the lowest dose is the NOSTASOT dose. This assumes that the lowest dose is a control group, and this convention might not be meaningful otherwise.
Value
a list with two components
NOSTASOT 
character string identifying the NOSTASOT dose. 
p 
numeric vector of the pvalues of the tests actually performed. 
The last element corresponds to all doses included, and will not be missing. pvalues for tests that were not actually performed due to the procedure stopping are set to NA.
Author(s)
Aniko Szabo, aszabo@mcw.edu
References
Tukey, J. W.; Ciminera, J. L. & Heyse, J. F. (1985) Testing the statistical certainty of a response to increasing doses of a drug. Biometrics 41, 295301.
See Also
trend.test
for details about the available trend
tests.
Examples
data(shelltox)
NOSTASOT(shelltox, test="RS")