Fourth place is rationalized invitation.
A rationalized invitation means finding a third-party reason to make your invitation reasonable, or at least appear reasonable. The most typical example here is asking a girl for a favor. For instance, most girls are good at putting together outfits. You could tell her that you will be the host at your company’s party next week and ask her to help you pick out clothes—whether it’s sending you links or meeting up in person, both are possible. If you don’t manage to meet up right away, after she helps you, you can use this as an excuse to thank her by inviting her out for dinner, which usually works. That said, this method is certainly less successful than the next three types of invitations.