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As mentioned above, though, you really should be testing more than one alternative, so you can be sure your eventual new tree is as effective as possible. Typically, we’ll test 2-3 proposed trees against each other (and against the existing baseline tree), then we’ll test a “best of” hybrid of the two in a second round.
For more on testing alternative trees against each other, see The design phase in Chapter 3.
Which part of the tree?
If you’re testing a small or medium-sized tree (say, < 500 items), you will normally test the whole tree – no major pruning required.
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For more on pruning trees, see Which part of the tree? in Chapter 6.
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