Skip to main content

StatsShapiroWilkTest

StatsShapiroWilkTest [/Q/Z] srcWave​

The StatsShapiroWilkTest computes Shapiro-Wilk statistic W and its associated P-value and stores them in V_statistic and V_prob respectively.

Flags​

/QNo results printed in the history area.
/ZIgnores errors.

Details​

The Shapiro-Wilk tests the null hypothesis that the population is normally distributed. If the P-value is less than the selected alpha then the null hypothesis, normality, is rejected.

The test is valid only for waves containing 3 to 5000 data points. The operation ignores any NaNs or INFs in srcWave.

Example​

// Test normally distributed data	
Make/O/N=(200) ggg=gnoise(5)
StatsShapiroWilkTest ggg
W=0.995697	 p=0.846139	// p>alpha so accept normality

// Test uniform distribution
Make/O/N=(200) eee=enoise(5)
StatsShapiroWilkTest eee
W=0.959616	 p=1.7979e-05	// p<alpha so reject normality