translation.en: In fact, in the last few years, there's been an explosion in research on happiness. For example, we've learned a lot about its demographics, how things like income and education, gender and marriage relate to it.
translation.zh: 其实，在过去的数年里，对于幸福的研究 有了一些突破性的进展。比如，我们通过对 人口统计学的研究了解到，外界因素诸如收入 和教育，性别与婚姻状况对幸福感有一定的影响。