Via Marginal Revolution, the "girl named Florida" problem.
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I've been reading Leonard Mlodinow's The Drunkard's Walk: How Randomness Rules our Lives. The book covers the Monty Hall problem, Bayes's Theorem, availability bias, the illusion of control and so forth. If these are unfamiliar, look no further for an entertaining account.
On the other hand, I can't say that I learned much I didn't already know. Nevertheless, I still enjoyed reading the book - it's well written and filled with interesting nuggets (Did you know that the great mathematician Paul Erdos refused to believe that you should switch doors?). If you teach probability theory or intro stats you will find lots of good examples to brighten up your lectures.
One problem did intrigue me. Suppose that a family has two children. What is the probability that both are girls? Ok, easy. Probability of a girl is one half, probabilities are independent thus probability of two girls is 1/2*1/2=1/4.
Now what is the probability of having two girls if at least one of the children is a girl? A little bit harder. Temptation is to say that if one is a girl the probability of the other being a girl is 1/2 so the answer is 1/2.
Was reading an absolutely fascinating account of two days in Istanbul from Michael Palin's book on his travels through New Europe.
Nowhere do history and geography merge as spectacularly as they do here, at the end of Europe and the beginning of Asia, where the Mediterranean meets the Black Sea. The great north-south, east-west corridors converge here and the city built on these low hills, by its various names of Byzantium, Constantinople and Istanbul, has been at the centre of world affairs longer than any other.
The location seems to heighten ordinary experience. Views seem more dramatic, departures and arrivals more significant, encounters more promising, awareness sharper. Istanbul always strikes me as a city with a foot in two distinct worlds and I can't imagine it ever jumping completely onto one side or the other.
As Orhan Pamuk says in his book on the city, 'Istanbul's greatest virtue is its people's ability to see the city through both Western and Eastern eyes.'
I set out across the Galata Bridge, my back to the great Ottoman and Byzantine monuments, heading up to Pera, once a colony of Genoese merchants. Fishermen line the bridge and flat-topped water taxis slide beneath it with inches to spare.
Check out Palin's travelogues some time if you haven't already.