What is the pay philosophy? o Pay-for-Performance? o Seniority? o Pay-for-Knowledge?

Pay depends on all of the above.All that matters is,Time to
Market.
Anyone of these 3 gets highest priority based on time,supply
and demand.
As of my philosophy of pay ,none of these is considered alone.

For any 
-If they well 'Performed' in academics,their 'knowledge'
makes them to get 'seniority' in their job.

-If they well 'Performed' in work, their 'Seniority' makes
them to acquire knowledge and  which becomes skill.

Pay philosophy varies based on organization philosophy too.