这里应该是省略了另外一个as
前面肯定还有提到另外一件事吧,这里省略是可以的
个人见解
为什么要倒装呢
Equally as important as questionnaire design is establishing a process of gathering data which will obtain a representative sample of cusomers,and which keeps bias to a minimum.
或者establishing a process of gathering data which will obtain a representative sample of cusomers,and which keeps bias to a minimum is Equally as important as questionnaire design.
个人觉得后面一句更合适.