The rhetorical appeal of ethos relies on the recipient’s emotions logic and reasoning the speaker’s credibility the tragic heroine’s flaw

The rhetorical appeal of ethos relies on the speaker's credibility.
It is about the speaker clearly mentioning his or her sources and giving proof for his or her claims. Emotions are about pathos, and logic and reasoning about logos. The tragic flaw is called hamartia.

The best sociological research method would have to be using experiments although it has some disadvantages as well