The following is one of the examples provided in the 'Comparisions' section of the Sentence Correction workshop:

The article questioned the popularity of Jazz compared to Classical music.

The correct version is as follows:

The article questioned the popularity of Jazz compared to that of Classical music.

My questions is why are they using "Compared to" ? Aren't they supposed to use "Compared with"? Aren't Jazz and Classical are both types of Music?

According to Spidey's notes on Sentence Correction, "Compare usually takes the preposition 'to' when it refers to the activity of describing the resemblances between unlike things"

"Compare takes 'with' when it refers to the act of examining two like things in order to discern their similarities or differences"

Thanks!