Good morning everyone! I am Lam Ki Fung from 5C. Today, I would like to share a book called Freakonomics, written by Steven D. Levitt and Stephen J. Dubner, with all of you.

Schoolteachers are professional and strict. Have you ever thought that they are counterparts of sumo wrestlers? What they have in common is, they both cheat.

Under a new policy, a school with low reading scores in Chicago would be placed on probation and face the threat of being shut down, its staff to be dismissed and reassigned. Schoolchildren, of course, have had incentive to cheat for as long as there have been tests. But high-stakes testing, that are annual standardized tests to students in elementary and secondary schools, is encouraging and giving reasons for teachers to cheat. There are few ways to inflate students’ scores. A teacher can simply give students extra time to complete the test. If they obtain a copy of the exam early, they can prepare the students for specific questions. More broadly, she can “teach to the test,” basing their lessons on questions from past years’ exams, which isn’t considered cheating but certainly violates the spirit of the test. They are persuaded by a very good reason: teacher cheating is rarely looked for, hardly ever detected, and just about never punished.

At the same time, a wrestler’s ranking is based on his performance in the elite tournaments that are held six times a year. If he finishes the tournament with a winning record, that is eight victories or better, his ranking will rise. A wrestler near the top of this elite pyramid may earn millions and is treated like royalty. So wrestler entering the final day of a tournament on the bubble, with a 7-7 wining and losing record, has far more to gain from a victory than an opponent with a record of 8-6 has to lose. However, from statistical results, 7-7 wrestler’s actual win percentage against 8-6 and 9-5 opponents almost doubles the predicted win percentage. Since so much depends on a wrestler’s eighth win, it may be enough to prove that a match is rigged.

Both teachers and sumo wrestlers are cheating under a basic economic principle─incentives. Economics is, at root, the study of incentives. How people get what they want, or need, especially when other people want or need the same thing. There are three basic flavors of incentive: economic, social and moral. Very often a single incentive scheme will include all three varieties.

In this book, more real life cases are analyzed with basic economic principles and theorems. Why do drug dealers still live with their Moms? Where have all the criminals gone? What makes a perfect parent? All these questions are answered with interesting findings and investigations with elaboration of economic theories. Do borrow this book to deepen your understanding on the happenings around you. This is the end of my book sharing. Thank you!