Now the intervention studies are stronger methods than the epidemiology studies but they're also more difficult studies to do.

相比传染病学研究,干预性研究更有效,但也更难执行

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选

That's part of public finance--is learning how to modify the tax system so that it works pretty well.

公共财政学的一个课题就是,研究如何改进税收制度，使其更有效。

耶鲁公开课 - 金融市场课程节选

Then, they did preliminary studies of safety and effectiveness in people.

接着,研究人员对疫苗在人体中的,安全性和有效性进行初步研究

耶鲁公开课 - 生物医学工程探索课程节选

Of course, the cyclic steps that we've taken to do this apply not just for breaking down reactants and product into the elements in their standards states, but of course we could also look at whole sets of reactions and write cycles as well, right.

当然，我们这里用的循环的,步骤不仅仅在把生成物,和反应物拆成其标准状态下,的元素时有效,我们也可以研究整个一系列,反应并写出相应循环。

麻省理工公开课 - 热力学与动力学课程节选

It's a more powerful method than something called a cross-sectional study, and I'll come back in a later lecture and talk about these in more detail, but a cross-sectional study means you're taking a snapshot of a population of people at one time.

这种方法比所谓的横断面研究更加有效,我将在以后的课中,再仔细讨论这个问题,但横断面研究是指,你一次记录下一群人的状况

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选