At an absolute minimum you should be collecting lots of statistics and using them to train a bayesian candidate filter to estimate hiring probability (the same

At an absolute minimum you should be collecting lots of statistics and using them to train a bayesian candidate filter to estimate hiring probability (the same architecture as a bayesian spam filter would work). If you find yourself wanting something more advanced than that, random forests would be a good match here, as would clustering the candidates using DBNs or simply k-means and then using base rates. Also, if you haven't looked at https://www.kaggle.com/competitions https://www.kaggle.com/competitions you really should -- they're similar to what you're doing, only for machine learning.