Would learning R benefit me in a prop trading role and my own trading to a degree ?
It's a language for performing statistical calculations and then displaying the results graphically. Surely that's the sort of thing anyone in your field does on a regular basis? I'm mildly staggered you're studying economics and finance, but haven't come across it.
You can get everything you need for free. Since you don't have an IT background I assume you will be working on Windows. As such I'd recommend downloading Visual Studio 2015 Community and R Tools For Visual Studio. That's probably the easiest entry point. Visual Studio is a very user friendly programming environment (whether you are developing Python, C++, C#). That said, I'm sure the Linux boys will chime in shortly and roundly lambast me.

Start with some basic tutorials such as these and see how you get on.
No more spoon feeding. Time to do some leg work yourself.
I met with a private equity exec a few months back. I asked him how I can stand out these days on my resume and he said saying you are an expert at financial modelling or a programming language can help since everything is "quantitative and statistical these days".
Hmmm, a 'private equity exec' eh? No comment.
Excel just doesn't cut it in my opinion.
And hasn't done for complex tasks for many, many years. Doesn't stop people using it though...and usually for the most inappropriate tasks.
I'm reminded of this debacle.
You'd be amazed how widely used it is within the finance community. Seriously. People will try to shoe-horn everything into a spreadsheet.

