The parameters for reward and recognition in any industry are almost the same.
1) Attendance
I particularly feel that attendance is one parameter that shows an employee's dedication towards their work. Whenever I hire a new individual, I always take a look at their previous company's attendance.
2) Productivity
Here, you need to get in touch with the operations managers and ask them to rate the employees on their productivity.
3) Speed of Improvement
Now, this is a little tricky. This is related to productivity; however, it needs to be perceived a little more broadly. You need to ask the operations to rate the employee separately on their amount of productivity (point 2) and on the speed or rate at which their productivity is growing.
Let me give you an example here. There are 3 candidates: A, B, and C. All three have completed a year in the system. However, A scores high on attendance, low on the other two parameters. B scores high on the first two; however, C scores high on attendance, low on productivity, but very high on speed/rate of improvement. In such a case, C is a better employee among these three!
Regards.