MistakesWereMade

I'm not mad at my advisor for not responding to my email; I just sent it anyway. If I am right,and I'm 85% sure I am, there is no redeeming this project though. It could potentially be reworked after the conference if we were able to access additional data (this is all secondary data analysis), but the only sample I think would be suitable is under a publisher's embargo until fall sometime. As for my advisor dismissing my concerns, I don't think he will do so after seeing what I sent him and maybe re-running my code himself for good measure. I am more worried about him being angry that I did not catch this earlier. I myself feel like I should have caught this earlier considering how many times I have read the paper the method is in, as poorly written as it is. In addition to this, I have found another problem with the method that would prevent us from doing something else with the data my advisor planned to do. While it does not completely destroy the project like the other problem, it is such a simple thing that I really have no excuse to have missed it. I didn't email this tidbit to him yet because I didn't want to send two freak out items in one email.

wrong batch of numbers to do any of the analysis, unfortunately :-( Oh, and it's a poster presentation, but still not great. I am editing my post to specify a poster now. How I worded it, it's not really clear. I also can't afford to pay for the plane and hotel if they don't refund me. I haven't heard of anyone doing something like that. If my advisor doesn't reply soon with some kind of solution, I'm honestly consider faking illness or something. I don't know what else to do.

My advisor assigned me a project using a statistical method I don't think he fully understood. It's new, one he hasn't used before, and it is in a dense, poorly written article. I have expressed to him that I felt we didn't understand it well enough, that we should consider collaborating with others to make sure the method was tenable, and that I felt it might not work. However, he blew these concerns off. When the initial results looked promising, I let it go. A few months later, my latest results look weird as hell. I reread the article for hundredth time to see if we had missed something. I think I found it. I have good reason to believe that our data violate a key assumption of the method (not described by the authors!) and that our results are complete garbage. The problem is that I am signed up to present these results as a poster in a few months time at a conference to which I have already been accepted and funded to attend. I don't know how I can back out with my plane and hotel already bought by the department. What do I do? Keep mum? It's wrong and I'm worried someone will find me out anyway. I have emailed my advisor, but he is on vacation and hasn't responded yet. Please proceed from the assumption that I am correct. I don't need to troubelshoot a scenario where everything is A OK. I need to troubleshoot the potentially terrible mistake I have made. Even though everyone in the field knows that beginning students don't design these projects, my head is on the chopping block; I am ultimately responsible for the research I put my name on. Knowing what I know now, I won't let it get to the publishing phase before the issues I identified are resolved, but what do I do about the conference?