Rewarding high performing teachers

The media is reporting today that the Australian federal government has set in place a scheme that rewards high performing teachers with bonuses. On the surface, rewarding high performing teachers with bonuses sounds like a great idea. The troubles I perceive with this scheme is that it assumes that motivating good teaching is simply a matter of money and the criteria the government is going to use to identify high performing teachers are inadequate.

According to this news article, “teachers will be assessed through student performance data, lesson observations, parental feedback and teacher qualifications” as well as the controversial and compulsory NAPLAN literacy and numeracy tests. The main issues I have with this are:

There is enormous scope in the performance criteria for task corruption, not to mention the inherit inaccuracy of the criteria themselves. For example they seem to be correlating parental feedback and teacher qualifications with teacher quality when there are obvious flaws with this approach. I should imagine the private schools, who are often more concerned about their public image than their curriculum, are already planning on how to corrupt the underlying intent of this task to their marketing advantage.
Stick and carrot does not work with any task that is cognitive in function. Motivation for improvement for workers with cognitive functions comes from autonomy, mastery and purpose, not financial reward.
The problems inherit in the NAPLAN process are well known and publicized. Reinforcing a questionable process like NAPLAN by linking it to a measure of teaching quality seems somewhat bizarre to me.