How old was he?

The truth is that most of us are over confident about our ability to predict things. Allow me to show you…

For each of the questions below, provide a numerical range that you are 90% sure contains the correct answer. In particular, if you have no idea then give a very wide range; and if you happen to be quite certain then give a narrow range.

Please try your best, but don’t look up the answers or cheat by scrolling down to the bottom!

1. What was Martin Luther King, Jr.’s age at death?
2. What is the length of the Nile River?
3. How many countries belong to OPEC?
4. How many books are there in the Catholic version of the Old Testament?
5. What is the diameter of the moon?
6. In what year was the Boeing 747 introduced?
7. In what year was Mozart born?
8. What is the gestation period of an Asian elephant, in months?
9. What is the air distance from London to Tokyo?
10. What is the depth of the deepest known point in the ocean?

Now have a look at the answers below. If you are perfectly calibrated then 90% of your intervals (no more, no less) should contain the right answers.

How did you get on? Did you get 90% correct? If so, if I were a client I’d let you estimate legal fees for a matter you were working on for me. If you got a much lower percentage correct, I’m not sure I’d trust your judgement!

Apparently this is a well-known psychological phenomenon. Even when we’re 100% confident we know the answer to something, we’re wrong on average 20% of the time. Bit depressing really.

So it’s not just lawyers getting the fee estimates wrong. We’re all at it!

Pass it on to your colleagues. See who you can trust with their estimates.

For answers scroll  down below…

Answers: 1. 39 years old: 2. 6,853 km or 4,258 miles: 3. 12 member states: 4. 46 books: 5. 3,475 km or 2,159 miles: 6. 1970 by PanAm: 7. 1756 in Salzburg: 8. 18-22 months: 9. 9,577 km or 5,951 miles: 10. 10,971 m or 35,994 feet