The beauty of the experimental design is that it effectively rules out confounding variables; acoustic isolation assures that the female can respond only to the song structure itself.
实验设计的美妙之处在于它有效地排除了混淆变量；声学隔离确保了雌性只能对鸣声结构本身做出反应。
2
The study sounds simple, but the design of the experiments was actually somewhat complex, because the researchers had to overcome a number of confounding variables.
这个实验听起来很简单，但是实验的设计确实有一定程度的复杂性，因为研究人员不得不克服一些混淆变量。
3
Identify possible biases and confounding variables, both during the design phase of the study and the interpretation of the results.