- In statistics, Welch's t-test, or
unequal variances t-test, is a two-
sample location test
which is used to test the (null)
hypothesis that two po****tions...
-
quality ****urance, and
survey methodology,
sampling is the
selection of a
subset or a
statistical sample (termed
sample for short) of
individuals from within...
-
sound wave to a
sequence of "
samples". A
sample is a
value of the
signal at a
point in time and/or space; this
definition differs from the term's
usage in...
- quartiles,
generally differ from the
statistics of the
entire po****tion (known as parameters). The
difference between the
sample statistic and po****tion...
- is then used to
determine whether the
observed frequencies in each
sample differ from
expected frequencies derived from a
distribution combining the...
-
within the
sample differ from the
sample mean. If the po****tion
standard deviation is finite, the
standard error of the mean of the
sample will tend to...
- The
sample mean (
sample average) or
empirical mean (empirical average), and the
sample covariance or
empirical covariance are
statistics computed from...
- for a
study may
differ in
important ways from others.
Consecutive sampling, also
known as
total enumerative sampling, is a
sampling technique in which...
- the case
where the data are
normal but the
variances may
differ.) For
moderately large samples and a one
tailed test, the t-test is
relatively robust to...
-
importance if
suspected variation among them
warrants stratified sampling. If
subgroup variances differ significantly and the data
needs to be
stratified by variance...
