This is likely a result of X.I understand what this means, it's not ungrammatical, but it's not in my idiolect (=the variety of English specific to me). I'd have to write one of the following:
This is likely to be a result of X.Because the first type isn't in my idiolect, I can't tell whether it's proper 'academese'. It sounded informal to me, until I asked Twitter and was directed to this blog post by Lynne Murphy. It is apparently a UK/US difference. Why my students are using it, I don't know: presumably this usage is spreading to this country.
This is probably a result of X.