Two types of passives

I've noticed that there are two types of passives, and I am wondering what is the best way to distinguish between the two. One likes to call with pretty good hands and sometimes bad hands, but only bets or raises with the nuts or very close. The other likes to call with just about anything (jack high is possible with this type) and will typically bet only when bluffing.

While these are both losing player types, a bet from one means the exact opposite from a bet from the other. Does anyone know of any other common things or common stats that characterize players from these two passive groups?

[Bodhi]

The frequency with which they check-raise. The ones who almost never check-raise bet with legitimate hands (your first category). The second type rigidly and predicatably check-raises their good hands and donk-bets as a bluff, and every once in a while will raise/check-raise as a bluff.

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The frequency with which they check-raise. The ones who almost never check-raise bet with legitimate hands (your first category). The second type rigidly and predicatably check-raises their good hands and donk-bets as a bluff, and every once in a while will raise/check-raise as a bluff.

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Yeah, this seems right.. thanks