P(H/D) = [P(D/H) x P(H)] ÷ P(D). That is one common formulation of Bayes' theorem, and at the heart of the view of statistics associated with a mid-18th century Englishman, Thomas Bayes. I blogged about this in January. If you don't understand the notation above, and would like a primer, go here. I bring it up again because Bayesianism has attracted new attention in the blogosphere. Sometimes the above is called "Bayes' rule," because it suggests a rule for constantly updating your views of the likelihood of events. Your hypothesis of probability of H on Tuesday (the prior ) is to be updated according to what happens or doesn't happen Wednesday, thereby yielding the posterior probability. Econoblogger Noah Smith wrote a post he calls " Bayesian Superman." He combines a (male)...
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I mentioned last month that I was reading Simon Schama's new book, THE STORY OF THE JEWS. I should say now that I did make a discovery in there I consider valuable. This was the first time I have ever come across the name Yehudah Halevi. That isn't because he is obscure, only a reflection on my ignorance. Schama gives him a lengthy passage (given the presumptions and format of the book) from p. 278 to 291. Halevi was born in Spain, possibly in Toledo, in the late 11th century. He lived much of his life passing back and forth between Moorish-held and Christian-held areas of that peninsula, what Schama calls a perilous shuttling between rival sets of persecutors of Jews, seeking at any moment the more bearable life in the one zone or the other. He died in 1141, either on the way to Palestine or soon after having arrived. His philosophical significance is as one of several philosophers within the three great monotheisms (the three "peoples of the book" if y...
"The light dove, cleaving the air in her free flight, and feeling its resistance, might imagine that its flight would be still easier in empty space. It was thus that Plato left the world of the senses, as setting too narrow limits to the understanding, and ventured out beyond it on the wings of the ideas, in the empty space of the pure understanding. He did not observe that with all his efforts he made no advance...." I don't know German, so of course I have no idea what the original passage as Kant composed it would sound or feel like to someone who does. But Kant's prose has a reputation for, um, Teutonic heaviness. Yet unless his translators have given him a huge gift, this passage shows that he had a light poetic side. It seems to me to speak with great concision to the similarity/difference of Kant and Plato. They are both philosophers who distinguish between the apparently (or provisionally) real world on the one hand and the really real world on the oth...
Debt is traded very differently from most corporate equity. The secondary market for bonds gets along without the big listed exchanges that provide a central narrative in the world of corporate stock. Indeed, for a long time trades were negotiated and agreed upon through telephone calls. In the 1990s, it occurred to various pioneers that “we could use the internet for this” and they tried to create an exchange-like model, an anonymous central limit order book (CLOB). A company called Trading Edge created BondLink for this purpose. Perhaps a related development: in 1998, the chairman of the Securities and Exchange Commission at the time, Arthur Levitt, said in a speech at the Media Studies Center in New York, “Investors have a right to know the prices at which bonds are being bought and sold. Transparency will help investors make better decisions, and it will increase confidence in the fairness of the markets.” Well, more transparency is always greater than less if the d...
Keeping track of the news has become an increasingly dispiriting activity. The events of Thursday, July 17th are themselves sufficient to illustrate this. Malaysian Airlines 17, a commercial flight from Amsterdam to Kuala Lumpur, crashed in the Ukraine that day. Also, Israel began its ground offensive in Gaza. Meanwhile, the twittersphere was full of speculations about a giant hole in Siberia, something that looks much more ominous than the garden variety sinkhole encountered in places with variable water tables. The hole on the Yamal Peninsula looks positively apocalyptic, and has inspired tralk of everything from global warming, to alien attacks. U.S. business news made its contribution to the distressing tone of the day, as Microsoft announced tens of thousands of layoffs. Microsoft! Fourteen percent of its workforce. How can we wrap our heads around such news? The first was almost certainly a deliberate act of war, the second was quite certainly an esca...
Raphael Golb, pictured here, son of Normal Golb (see yesterday's discussion of who he is) is expected to surrender to authorities on Tuesday, July 22 to begin serving his sentence. This is despite a victory at the Court of Appeals, which discarded the felony charge against him, identity theft, and declared unconstitutional the New York statute on "aggravated harassment." I'm glad of his victories, by the way. When such offenses are on the books they render possible the criminalization of vigorous and free-wheeling debate on the sort of issues that the first amendment was, precisely, designed to protect. That left misdemeanor charges of forgery and impersonation still standing. Golb took part in internet debates about the Dead Sea Scrolls, one of the issues on which his father has made a reputation. Not surprisingly, Norman Golb's thesis on this point has been hotly contested, by (among others) Lawrence Schiffman, of New York University. In the wak...
The case is bizarre, on a number of grounds. A New York court has sentenced the man pictured here, Raphael Golb, on misdemeanor criminal impersonation and forgery charges. If this were just another petty crook, it wouldn't be worth our notice at Jamesian Philosophy Refreshed . But this is the son of an important scholar, and the crimes were committed on behalf of the proper interpretation of certain ancient texts, the lifework of that paternal inspiration. Raphael's father, Norman Golb, is known as an advocate of the view that the Essenes had no especially close association with the Dead Sea Scrolls . \ Why is that important? The Essenes, an ascetic sect of Judaism that disagreed firmly with both the Sadducees and the Pharisees, are mentioned by several ancient authors (Philo, Josephus, Pliny) and are widely thought to have withdrawn from the wicked world into the purer environment of Ein Gedi, near the shore of the Dead Sea. As ancient scrolls were discovered n...