I would qualify this better. Most people take a day off for an interview. If you explained to the interviewee that they were to turn up at 9am, would be given a

I would qualify this better. Most people take a day off for an interview. If you explained to the interviewee that they were to turn up at 9am, would be given a small project using X technologies, to be completed within the day to be ready for a code review at 3:30 and presented to the team at 4pm. Lunch would be provided and they would be paid for their time.