# Counteracting Perverse Incentive effects in 1902 Hanoi rat population

A perverse incentive is a reward system that has the opposite effect to the one intended.

In Hanoi, under French colonial rule, a program paying people a bounty for each rat tail handed in was intended to exterminate rats. Instead, it led to the farming of rats. https://en.wikipedia.org/wiki/Perverse_incentive

Question

Given our current knowledge of Game Theory, Biology, Population Dynamics and other relevant sciences: what would have been the most effective way to persuade the people of Hanoi to exterminate rats in a low-tech society in 1902.

Note: To prevent this being a mere matter of opinion or crazy ideas, I have added the hard science tag. Thus I'd like informed opinion on things like population dynamics and historical evidence of successes in wiping out 'vermin'.

World-building Context

Depending on the answers to this question, I may go on to ask other questions that will require plausible replies to the the above, for example:

Is there any way of measuring the effects on history, if rats had been wiped out worldwide in the early 20th century? What would the world look like without them?

Please don't answer this question but bear in mind they are my reason for asking. Many thanks.

This question asks for hard science. All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See the tag description for more information.

• Please concentrate on one question. Your bonus question is about an entirely different topic – Elmy Jan 22 at 10:27
• Tweaked the link from mobile wikipedia to normal - feel free to revert if it was intended – Pingcode Jan 22 at 10:43
• In the words of Lord Vetinari, tax the rat farms – Separatrix Jan 22 at 11:01
• "Hard science" and human behavior don't mix. Sociology, group dynamics, political science and economy are among the softest of soft sciences, sitting right on the boundary between proto-science and magical thinking. The so called sciences which are supposed to provide the answer are themselves matters of opinion. – AlexP Jan 22 at 11:38
• It reminds me of my energy company: on one side they award customer points for each consumed kWh, on the other side they stress the importance of energy saving – L.Dutch Jan 22 at 11:44