I'm a web novice too so take my advice as such .. My requirements are similar to yours, backend ANN's and frontend graph visualization. I'd go with whatever

I'm a web novice too so take my advice as such .. My requirements are similar to yours, backend ANN's and frontend graph visualization. I'd go with whatever you currently feel most comfortable with. Getting the first version out there in the fastest way possible will give you a chance to judge feasibility and traction. The minor differences between current popular languages and frameworks will the least of the problems in getting the app up and running (and honestly inspite of all the wars they don't matter all that much) As for me I'm using ROR/C++/Javascript.