"A story about probability"

DISCLAIMER: This story is purely fictional and any resemblance to any real life characters (or to yourself) is completely coincidental. The author takes no responsibility for any loss of life, ego, or whatnot resulting from the publication of this story.


In a place far far away, not too long ago (for they had concrete buildings and electron microscopes and other not-so-long-ago stuff), there lived some people. And they lived very happily there.

One day, some of these people started falling sick.

As sick people were not so happy, thus the Facility of Overall Complete Sciences (FoOCS for short) started to do some research.

And soon, indeed, they managed to isolate the germ that was making the kingdom not-so-happy. They called it Yet Another Naughty Germ (or YANG) for short, as Naughty people made mischief and made the kingdom not-so-happy-after-all. They called the disease YANGitis.

Now, being a very naughty germ, YANG only selectively infected people. In fact, it only infected people with a particular trait. Unfortunately, no one knew (or to this day, knows) what this trait is. We know, however (background info from some other sources unbeknown to to these people), that 90% of people did not have this trait. So YANG only infected 10% of people, making them so unhappy.

So FoOCS did some more research, and came up with a test to detect if people suffered from YANGitis. Unfortunately, being not as overall complete as its name suggested (a consequence of being too happy and complacent), the test gave 20% false positives and 10% false negatives (that is, if you don't have the disease, 20% of the time the test will say you have it etc).

So once the test was discovered, two clinics started administering the test. Like every story should have, there were good guys and bad guys. Everyone knew about the bad guys, but they were Happy bad guys, so no one bothered. The test was made compulsory for all citizens, so that everybody could be happy and live happily ever after.

Now the good guys were the Clinic of Health And RelaxZation (CHARZ). CHARZ studiously and dutifully gave the test to everyone who came there. CHARZ then sent all the people who tested positive to FoOCS for treatment, and they became a very happy lot once again.

However, the bad guys, (who refuse to reveal their names as they are bad guys), chose a more happy-go-lucky approach. They told everyone who visited them that they were free of YANG, and thus very happy.

So after a while, everyone in the nation was happy again and they lived happily ever after. Really?

The End? No....

Q1. Who is more accurate? CHARZ or the bad guys?

Q2. What is the moral of the story?

[ed: added comment button so this lamebrained riddle can actually be answered.]