It is also important to note that the study found only a correlation, as researchers did not prove for certain that optimism leads to a longer life.

还值得注意的是，该研究只是发现了一种关联，因为研究人员并不能明确证明乐观与长寿有必然联系。

youdao

Even the Harvard study did not prove a direct correlation but noted strong associations between exposure and risk of behavioral issues.

就连哈佛大学的研究也没有证明两者之间有直接的联系，但指出了这种接触与行为问题风险之间的强烈关联。

youdao

But while I'm convinced of the correlation in this study, I'm just not convinced of the causation.

但是我确定了这次研究的关联，我只是不确定原因。

youdao

But GMI's data were put to the test in an October 2009 study that measured the correlation of GMI's rankings to stock performance from mid-2003 to mid-2008.

FORBES: Magazine Article

The study found a correlation between the increase in stress and the number of days holiday taken by executives in the countries concerned.

ECONOMIST: A look at noteworthy articles from business journals

Flying Dog advertises its status as the favoured drink of the celebrated radical journalist Hunter S Thompson, and a 2012 study found a positive correlation between the concentration of microbreweries in a state and its likelihood to vote for Barack Obama.

BBC: US craft beer: How it inspired British brewers