A more thorough explanation:

Presumed bias is a type of bias that is assumed or implied. It is similar to implied bias, which means that bias is suggested or hinted at without being directly stated.

For example, if a news article about a political candidate uses negative language and focuses only on their flaws, it may be presumed that the writer has a bias against that candidate. Similarly, if a teacher consistently calls on male students more than female students, it may be presumed that the teacher has a bias towards male students.

Presumed bias can be harmful because it can lead to unfair treatment or discrimination. It is important to be aware of our own biases and to try to avoid making assumptions based on them.