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Options

This page is the control by control reference for the pages the Create Design builder shows for this design. What the design is and what it gives you is on Box-Behnken Designs. How each number is produced is on Math Details.

The page sequence

Select the Box-Behnken design > Enter Factor Names and Coding > Define outputs (responses) > Enter number of replicates and number of blocks > Center points.

Center points asks for one number. Its label depends on the design type and the replicate format, not on how many replicates or blocks the design has:

Design The label
2-level factorial, Stacked format Number of center points per block:
2-level factorial, Table format Number of center points per replicate:
every other design type Extra number of center points:

Below the box are two total lines, and both update as you type. With a single replicate and a single block they read Total number of center points: and Total number of runs:. Once the design is replicated or blocked they show the arithmetic instead, as Total center points: n replicates * m center points = t (or n blocks * ... in the stacked multi-block case) and Total runs: n replicates * m = t.

On this design the box is for EXTRA center points, and it starts at 0. Its label reads Extra number of center points:, and what you type is added to the default count in the table above. Typing 6 on a 3-factor design gives 9 center points and 21 runs, not 6 and 18. This differs from the CCD, whose Axial and center points page holds the total rather than an addition.

The design sheet records the block count followed by the word blocks.

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