martedì 22 marzo 2016

Dibattendo EMH

  • Definizione
  • 2 categorie di scettici: 1. i contrari ideologicamente e 2. i consulenti che non avrebbero niente da consigliare
  • Shiller: hindsight bias
  • Perchè esiste una regolamentazione e una banca centrale se vale EMH?
  • Nel momento in cui reputi buone alcune regole cessi di credere a EMH!
  • MIT Chicago Mason. Sapendo che il mercato è imprrfetto (pur considerandolo il meglio a disosizione) le regole ci saranno sempre come segno di speranza e di cammino verso la xfezione
  • Krugman e LTCM
  • Le bolle possono coesistere con EMH?
  • The peso problem
  • Xxx
  • The Price Isn't Always Right justin fox
  • Eugene Fama at Chicago in the late 1960s envisioned a market in which "security prices at any time 'fully reflect' all available information."
  • the world experienced financial crises long before anybody at the University of Chicago thought to string the words "efficient" and "market" together.
  • Finally, if all one means by "efficient market" is a market that's hard to beat, that's not such a wrongheaded idea at all
  • Robert Shiller -- a long-time critic of the efficient market hypothesis -- cobbled together an inflation-adjusted index of U.S. real estate prices going back to 1890 and found that (a) in the past, prices had declined for decades on end and (b) the rise in real home prices since 1997 was by far the sharpest on record. From these two pieces of data he drew the common-sense conclusion that the rise in housing prices wouldn't go on forever
  • Xxx
  • In Defense of Efficient Markets eric falkenstein
  • you make many gracious acknowledgements to the efficient markets hypothesis (EMH), such as the basic implication that it is very, very difficult to outperform the market....This is not a minor acknowledgment, but basically is the EMH theory.
  • I think this distaste for efficient markets comes from two sources. First, many people distrust the "invisible hand." They do not think markets are fair games that reward virtue and promote social welfare. Secondly, there are critics (stockbrokers, talking heads on CNBC, financial journalists) whose livelihood depends on markets being wrong;
  • Shiller. Shiller did not predict an aggregate housing decline; instead, he merely stated the recent increase in home prices was unlikely to continue.
  • Bolla: The market diagnosed the bubble......prices, not legislators, instigated the end of the insanity.
  • No one thinks markets are perfect, and EMH never says this. The proof that markets are efficient is that it is so improbable one can generate alpha -- something you, like most EMH critics, concede. But the implications do not seem obvious. That you were able to find one person in 2004 and turn his measured warning into something that would have drastically reversed the regulatory emphasis on weakening underwriting standards is classic hindsight
  • Markets Can Do Many Things Well, But Not Everything justin fox
  • why over the past two centuries we've developed central banks and financial regulations. Yet it is a reality almost completely ignored by the efficient-market approach to finance.
  • I'll be honest: I don't know what exactly the new rules should be.
  • Why Most Market Regulation is Useless And/Or Harmful eric falkenstein
  • As George Will writes, most regulation is championed by a confluence of Baptists and bootleggers,
  • Regole: irrilevanti o contrproducenti.
  • The first. Exemplified by things like short-sale downtick prohibitions, Glass-Steagall, and mortgage disclosure requirements, all of which are really irrelevant to protecting the retail investor.
  • A second type of financial regulation is downright counterproductive... Consider the Equal Credit Opportunity Act of 1974, a law which sat around not causing problems, until 1992 when Fed President Richard Syron realized he could use it as a club to get banks to lower home loan underwriting standards in the 1990s....Another example is the Clinton administration law putting a surtax on millionaires, which created an incentive to focus on option-based compensation for corporate executives.
  • Without regulation, markets correct themselves
  • In the bad old days prior to much financial regulation, or even a central bank, we had crisesevery twenty years: in 1819, 1838, 1857, 1873, 1893, and 1907. After a couple of years, though, things always got better, and growth was strong over this period. It is historical experience, not religious faith,
  • Much regulation is really about preventing competition,
  • Bold regulation is the triumph of hope over experience,
  • Back to the Myth of the Rational Market justin fox
  • So Eric, you're saying that some financial regulations are pointless, some are counterproductive, and some actually do good. Sounds about right to me. But it's not what the die-hard rational marketeers of the 1970s and 1980s were saying.
  • Xxx
  • We Need Less Regulation, Not More eric falkenstein
  • when you say something is imperfect, it should always be asked, "compared to what?" Some theoretical nirvana
  • Krugman Reviews Book He Didn't Read eric falkenstein
  • Justin Fox noted that I didn't read his book, because if I did he would have noted Fox's rather balanced treatment.
  • The LTCM strategy had nothing to do with a tweak to the Black-Scholes option formula.
  • Do Crashes Support or Disprove 'Rational' Markets? eric falkenstein
  • Noneconomists tend to think 'rational markets' is patently absurd, pointing to various asset bubbles such as the internet bubble,
  • To assert markets are irrational or inefficient, however, one needs to propose a measure of 'true value'... It is essential to have a specific alternative, because how do you know they are wrong unless you know the right answer?
  • Prices fluctuate more than we would like. But is it too much? The future is very uncertain, and in the US where so many prominent financial researchers work, we tend to forget we had a very fortunate 20th century
  • Xxxxx
  • Arnold Kling
  • MIT economists think markets are imperfect, therefore we need regulation.
  • Chicago economists think markets are perfect, therefore we don't need regulation.
  • George Mason economists think markets are imperfect, therefore we don't need regulation.
  • Bad stuff's going to happen from time to time. Get used it. But political and regulatory reality is such that this mindset is never going to prevail.
  • How to make money from a Nobel cause tim harford
  • Fama and Shiller disagree with each other.
  • EMH, is much maligned, so let me state it in the form that has spared me anxiety and saved me money over the years: it’s hard to beat the market,

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