Normal Distribution Methods Used in Different Procedures

Different IBM® SPSS® Statistics procedures offer different methods to approximate the normal distribution.

• Blom method. Normal P-P Plot, Normal Q-Q Plot, Rank Cases, and Linear Regression.
• Tukey method. General, Hierarchical, and Logit Loglinear analysis. Optional in Rank Cases, Normal P-P Plot, and Normal Q-Q Plot.
• Rankit method. Optional in Rank Cases, Normal P-P Plot, and Normal Q-Q Plot.
• Van der Waerden method. Explore, General Factorial ANOVA, Multivariate ANOVA, and Repeated Measures ANOVA. Optional in Rank Cases, Normal P-P Plot, and Normal Q-Q Plot.

Starting with release 6.1, all procedures (by default) break ties by using the mean rank of the tied cases.