1 - 2 shows a good 10+ HCPs while
Either of these raises requires 5+ card support in Clubs or 4+ in Diamonds.
Most experts say that with a weak hand, you should jump-raise even if you have a 4-card major, the idea being that if you are weak, the opponents are going to get into the bidding, so you want to shut them out right away, or at least take away as much bidding space as possible.
On Larry Cohen's web site, Cohen says: In no case should a minor be raised if responder has a 4-card major.
He also says that Inverted Minors should be on even if responder is a passed hand, but not after a double or overcall.
Cohen also recommends that after a raise of 2, a bid of 2 by opener shows control in the suit bid. If responder then bids 2N or 3 of opener's minor, it can be passed, while any other response is forcing to game.
In SAYC, Inverted Minors are not used, so the default in BidBase for 1 - 3 is