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| 45 |
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45 |
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| 46 |
The presence of ties always generates a warning, since continuous
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46 |
The presence of ties always generates a warning, since continuous
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| 47 |
distributions do not generate them. If the ties arose from rounding
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47 |
distributions do not generate them. If the ties arose from rounding
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| 48 |
the tests may be approximately valid, but even modest amounts of
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48 |
the tests may be approximately valid, but even modest amounts of
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| 49 |
rounding can have a significant effect on the calculated statistic.
|
49 |
rounding can have a significant effect on the calculated statistic.
|
| 50 |
|
50 |
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| 51 |
Missing values are silently omitted from \code{x} and (in the
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51 |
Missing values are silently omitted from \code{x} and (in the
|
| 52 |
two-sample case) \code{y}.
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52 |
two-sample case) \code{y}.
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| 53 |
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53 |
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| 54 |
The possible values \code{"two.sided"}, \code{"less"} and
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54 |
The possible values \code{"two.sided"}, \code{"less"} and
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| 55 |
\code{"greater"} of \code{alternative} specify the null hypothesis
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55 |
\code{"greater"} of \code{alternative} specify the null hypothesis
|
| 56 |
that the true distribution function of \code{x} is equal to, not less
|
56 |
that the true distribution function of \code{x} is equal to, not less
|
| 57 |
than or not greater than the hypothesized distribution function
|
57 |
than or not greater than the hypothesized distribution function
|
| 58 |
(one-sample case) or the distribution function of \code{y} (two-sample
|
58 |
(one-sample case) or the distribution function of \code{y} (two-sample
|
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| 63 |
Thus in the two-sample case \code{alternative = "greater"} includes
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63 |
Thus in the two-sample case \code{alternative = "greater"} includes
|
| 64 |
distributions for which \code{x} is stochastically \emph{smaller} than
|
64 |
distributions for which \code{x} is stochastically \emph{smaller} than
|
| 65 |
\code{y} (the CDF of \code{x} lies above and hence to the left of that
|
65 |
\code{y} (the CDF of \code{x} lies above and hence to the left of that
|
| 66 |
for \code{y}), in contrast to \code{\link{t.test}} or
|
66 |
for \code{y}), in contrast to \code{\link{t.test}} or
|
| 67 |
\code{\link{wilcox.test}}.
|
67 |
\code{\link{wilcox.test}}.
|
| 68 |
|
68 |
|
| 69 |
Exact p-values are not available for the two-sample case if one-sided
|
69 |
Exact p-values are not available for the two-sample case if one-sided
|
| 70 |
or in the presence of ties. If \code{exact = NULL} (the default), an
|
70 |
or in the presence of ties. If \code{exact = NULL} (the default), an
|
| 71 |
exact p-value is computed if the sample size is less than 100 in the
|
71 |
exact p-value is computed if the sample size is less than 100 in the
|
| 72 |
one-sample case \emph{and there are no ties}, and if the product of
|
72 |
one-sample case \emph{and there are no ties}, and if the product of
|
| 73 |
the sample sizes is less than 10000 in the two-sample case.
|
73 |
the sample sizes is less than 10000 in the two-sample case.
|
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