I'm building a graphical visualization of this data, you can check the project here: http://jlhonora.github.io/stackexchange-predictions/ . To visualize it you need to download the data and then upload it. It would be great if the app could be granted access via OAuth or an alternative.
fkeyparameter is sent along with the request, could be a CSRF token or an encoded user id. If the former is the case, then the user is obtained through a cookie, which I wouldn't be able to emulate either.