Two-level designs impose the same template on all factors. The XN page removes this constraint: Each factor has its own number of levels, which reflects the reality of the industry—three suppliers, two speeds, five tools.
The « Maximum number of levels » (2 to 6) sets the upper limit, and the factor table displays that many columns, N1 … Nn. A factor for which you enter only one level is ignored : It does not vary; there is no effect to estimate.
The list of possible layouts adapts to the exact structure of your levels. Depending on the situation:
- fullDOE : the full package, all options included. Always offered, five-star, and quickly becomes too expensive; ;
- the fractional tables L4, L8, L9, L12, L16, L18, L25, L27, and fractional designs with 12, 16, 18, or 24 trials, depending on the level distribution; ;
- the Final Screening Design, when all factors have three levels.
💡 The XN page is the right solution to a very common need that isn't well met elsewhere: a factor qualitative with multiple modalities combined with quantitative factors. Whereas Response Surface and Filling reject qualitative data, XN accepts it natively.
⚠️ The quality of XN fractional plans varies significantly depending on the table and The number of factors: The same table may be worth five stars in one configuration and only one star in another. Read the “Quality” column before making your choice, and don’t automatically reuse the table from a previous plan.