I listened to a radio interview of a famous investigator in Hong Kong recently. It was enlightening.
The details of the project have been described by my friend earlier. [see http://ccszeto.blogspot.com/2010/03/study.html] In brief, the investigator obtained one of the biggest research grants from our Government to study the prevalence of a disease among youngsters that was believed to be both common and important. After screening hundreds of subjects, the investigator failed to find any positive case.
Like many epidemiological studies, this study claimed to select potential subjects randomly. However, the selected subjects had the right to choose whether to proceed to the test. In such a situation, it is of vital importance to compare subjects who agreed to be tested and those who refused. If the two groups had major differences, the data obtained would be inaccurate or even misleading.
If I received a big grant from the Government and got such results, I probably would not be able to sleep. However, that investigator was obviously better than me. “The project is a huge success,” he explained to the host. “If the collaborating parties agree, we would definitely extend the project for another year.”
Somehow my mind drifted to a short story.
One day, Emperor Kangxi (康熙) disguised himself as a commoner and walked around Beijing. He met a crowd and found that a murderer was about to be executed. To his surprise, the poor prisoner looked very young and certainly did not match the description of the middle-age murderer. He put the execution to a halt and confirmed that the rich murderer paid a government official to exchange a young boy for him. Furious, he ordered a thorough investigation of the event and other death sentences in the past.
The Prince who took charge of the investigation was the most likely successor of the Emperor. After discussing with his advisors, he concluded that the investigation would reveal uncountable cases of corruption and mishaps. This would create much trouble among senior officials and he might lose their support. Therefore, he just pretended to do something and held a series of investigations and interrogations.
A few months later, the Prince submitted the final report to the Emperor. “In conclusion,” he described, “no other cases of inappropriate judgments or executions were identified. The judges and officials have done an excellent job and should be commended.”
At this, Emperor Kangxi hit the table and scolded, “What a coincidence! There was just one case of corruption in the whole of China and it happened to be seen by the Emperor!”
Well, our Government is not Kangxi after all. Perhaps the disease really does not exist in Hong Kong.