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The NPAR1WAY Procedure |

**EXACT***statistic-options < / computation-options >***;**

The EXACT statement requests exact tests for the specified statistics. Optionally, PROC NPAR1WAY computes Monte Carlo estimates of the exact

Exact

Table 47.3 lists the available

If you list no

Option |
Exact Tests Computed |

AB | Ansari-Bradley Test |

KLOTZ | Klotz Test |

MEDIAN | Median Test |

MOOD | Mood Test |

SAVAGE | Savage Test |

SCORES=DATA | Test Using Raw Data as Scores |

ST | Siegel-Tukey Test |

WILCOXON | Wilcoxon Test for Two-Sample Data |

Kruskal-Wallis Test for Multisample Data | |

VW | Van der Waerden Test |

**ALPHA=**-
specifies the confidence level for the confidence
limits for the Monte Carlo
*p*-value estimates. The value of the ALPHA= option must be between 0.0001 and 0.9999; the default is 0.01. A confidence level of results in % confidence limits. The default of ALPHA=0.01 results in 99 percent confidence limits. If is between 0 and 1 but is outside the range of 0.0001 to 0.9999, PROC NPAR1WAY uses the closest range endpoint. For example, if you specify ALPHA=0.000001, PROC NPAR1WAY uses 0.0001 to determine confidence limits. The ALPHA= option invokes the MC option. **MAXTIME=***value*-
specifies the maximum clock time (in seconds) that PROC NPAR1WAY can use
to compute an exact
*p*-value. If the procedure does not complete the computation within the specified time, the computation terminates. The value of the MAXTIME= option must be a positive number. The MAXTIME= option is valid for Monte Carlo estimation of exact*p*-values, as well as for direct exact*p*-value computation.

See the section "Computational Resources" for more information. **MC**-
requests Monte Carlo estimation of exact
*p*-values, instead of direct exact*p*-value computation. The ALPHA=, N=, or SEED= option also invokes the MC option.

The MC option is available for all the EXACT statement*statistic-options*. Monte Carlo estimation can be useful for large problems that require a great amount of time and memory for exact computations but for which asymptotic approximations may not be sufficient. See the section "Monte Carlo Estimation" for more information. **N=***n*-
specifies the number of samples for Monte Carlo estimation.
The value of the N= option must be a positive integer, and the default is
10000 samples. Larger values
of
*n*produce more precise estimates of exact*p*-values. Because larger values of*n*generate more samples, the computation time increases. The N= option invokes the MC option. **SEED=***number*-
specifies the initial seed for random number generation for
Monte Carlo estimation. The value of the SEED= option must be a positive
integer. If you do not specify the SEED= option, PROC NPAR1WAY uses the time
of day from the computer's clock to obtain the initial seed.
The SEED= option invokes the MC option.

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