How to Measure Quality of Hire?

I'm not sure if this was brought up before I was late. My Uber driver got rear ended on the way here. But yes, from a quality of hire standpoint, looking at your HDS and looking at the job boards that you're plugged into. Career fairs, job fairs, employee referrals. What is the ROI on all of these things? How are you measuring them? There's a theme coming up here where it's just the data aspect of it all. And, oh, go for it. Do we, we've got Microsoft ready to whip around. Questions anybody? Raise the rail.