Are there other indicators or tricks or rules of thumb that just off the top of your head come to you as useful mechanisms for doings this as well?

当然还有没有其他的,一些暗示或者说技巧,或者规则之类有用的办法呢？

哈佛公开课 - 计算机科学课程节选

Notably there are different indicators.

显而易见，有不同的指示标志。

耶鲁公开课 - 金融市场课程节选