NOSTASOT {CorrBin} | R Documentation |
The NOSTASOT dose is the No-Statistical-Significance-Of-Trend 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.
NOSTASOT(cbdata, test = c("RS", "GEE", "GEEtrend", "GEEall", "SO"), exact = test == "SO", R = 100, sig.level = 0.05, control = soControl())
cbdata |
a CBData object |
test |
character string defining the desired test statistic. See trend.test for details. |
exact |
logical, should an exact permutation test be performed. See trend.test for details. |
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 soControl . See there for the names of the settable control
values and their effect. |
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 step-down manner with the same sig.level
type I error rate at each step and
still control the family-wise 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.
a list with two components
NOSTASOT |
character string identifying the NOSTASOT dose. |
p |
numeric vector of the p-values of the tests actually performed. The last element corresponds to all doses included, and will not be missing. p-values for tests that were not actually performed due to the procedure stopping are set to NA. |
Aniko Szabo, aszabo@mcw.edu
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, 295-301.
trend.test
for details about the available trend tests.
data(shelltox) NOSTASOT(shelltox, test="RS")