Two-sample t Test

DESCRIPTION:

This function is used by the Two-sample t Test dialog.

USAGE:

menuTTest2(data=NULL, x, y, groups.p=F, mu=0, 
           alternative="two.sided", t.paired="Two-sample t", 
           var.equal=F, conf.level=0.95, print.object.p=T) 

REQUIRED ARGUMENTS:

x
a numeric vector. NAs and Infs are allowed but will be removed. If groups.p is FALSE, x is the first sample. If groups.p is TRUE, x is the response variable of two samples and y is the grouping indicator.
y
a numeric vector. NAs and Infs are allowed but will be removed. If t.paired="Paired t", then x and y must have the same length, and observation pairs x[i], y[i] with at least one NA or Inf will be removed. If groups.p is FALSE, y is the second sample. If groups.p is TRUE, y is the grouping indicator with the first observation indicating the first sample. Only two groups are allowed.

OPTIONAL ARGUMENTS:

data
a data frame in which to interpret the variables named in the x and y. If this is missing, then x and y must be two vectors.
groups.p
if TRUE, x is the response variable of two samples and y is the grouping indicator. If FALSE, x is the first sample and y is the second sample.
mu
a single number representing the value of the mean or difference in means specified by the null hypothesis.
alternative
a character string, one of "greater", "less" or "two.sided", or just the initial letter of each, indicating the specification of the alternative hypothesis. For the paired t-tests, alternative refers to the true mean of the parent population in relation to the hypothesized value mu. For the standard and Welch modified two-sample t-tests, alternative refers to the difference between the true population mean for x and that for y, in relation to mu.
t.paired
if "Paired t", x and y are considered as paired vectors.
var.equal
if TRUE, the variances of the parent populations of x and y are assumed equal. This should be supplied only for the two-sample (i.e., unpaired) tests.
conf.level
confidence level for the returned confidence interval, restricted to lie between zero and one.
print.object.p
if TRUE, the result of the test is printed.

VALUE:

a list of class "htest". See the help file for t.test for details.

SEE ALSO:

, .