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Main Menu BIPLOTS

The term "biplot" usually refers to the biplot of PC1 vs. PC2. However, there are other types of biplots, which might be useful in helping the analysis (follow this link). In particular, the 3-D biplot module is very useful for a better understanding the data.

In addition to the default biplot of PC1 vs. PC2, which may be referred to as the "primary biplot", GGEbiplot provides biplots of a higher order or secondary biplots:

• PC3 vs. PC4,
• PC5 vs. PC6,
• PC1 vs. PC3, 
• PC2 vs. PC3

For users who are familiar with AMMI (Additive Main effect and Multiplicative Interaction) analysis, GGEbiplot also generates the two most commonly used AMMI biplots:

• AMMI1 biplot (Main Effect vs. IPC1), and
• AMM2 biplot (IPC1 vs. IPC2)

In addition, GGEbiplot also provide a 3D-biplot viewer:

• 3D-biplot

Note: 

• A higher order biplot may be useful when patterns are found in the biplot of PC1 and PC2.
• When the doubled-centered model is used, i.e., when entry and tester main effects are removed from the data before singular value decomposition, the PC's are referred to as IPC's, indicating that the PC's contains only the interaction component of the total variation. However, I don't see any use of this biplot except for gene expression data.