Visa application for Canada and no Invitation letter

I dont have a family in Canada , i have a job here in Nigeria as I work as a Software Engineer and a Process Architect for one of the biggest banks here. Now i want to go to Canada on temporary Residence visas, I ofcourse, since i do not have a family there chances of getting invitation got a bit harder and almost very impossible, hence i wanted to ask this very simple question, if I dont have any family member there in Canada can i still apply like that without invites? Are there chances of Visa refusals?