Saturday, August 04, 2007

How Do and How Should Human Beings Use Reference Classes (Relative Frequencies)?

James Franklin & Scott Sisson, Assessment of Strategies for Evaluating Extreme Risks, (ACERA Project No. 0602, March 2007):
[Previously enumerated] considerations suggest this important conclusion, which is central to the point of view of this report:
It is reasonable to give human intuition the “last word” in risk assessment, while at the same time trying to use formal statistical methods as a kind of prosthesis to supplement its known weaknesses.
A problem where the superiority of human intuition over formal methods is especially evident – and one very relevant to extreme risks – is the “reference class problem” (also called in artificial intelligence “multiple inheritance”). The most basic evidence for probabilities in an individual case is observation of a relative frequency (in a class of which the case is a member). For example, the probability that Tex is rich, given that Tex is a Texan and 90% of Texans are rich, is 0.9. But typically, a case is a member of very many classes, in which relative frequencies vary. And there is no useful theory explaining how to combine the probabilities arising from the different “reference” classes. For example, if the evidence is that Tex is a Texan philosopher, that 90% of Texans are rich and 10% of philosophers are rich, then it is impossible to say how to combine these two numbers to achieve a numerical probability that Tex is rich, on the given evidence. (H├íjek, 2006) The problem has caused a great deal of trouble in, for example, the law of evidence, where there is often evidence of different classes but it is of dubious legal relevance (Colyvan et al, 2001; Tillers, 2005), and in attempts to construct medical diagnosis expert systems, where combining evidence from different symptoms is essential but how to do it is theoretically poorly understood. (See also Caponecchia, 2007, section 4 for its relevance to communicating probabilities.)

Yet humans are very good at combining different kinds of evidence. Where they have an advantage over formal methods is that they can learn from long experience the comparative relevance of different reference classes. For example, they can learn enough about being Texan, being a philosopher and being rich to have some sense of whether being Texan or being a philosopher is more likely to be relevant to being rich. The vocabulary of natural languages is already attuned to naming concepts that are relevant to living, that is, are positively relevant in probabilistic inferences; which of them are most relevant to a particular inference is something that itself can be learned – but only over a long period, and in the context of very many other concepts.

That wide base of experience and the resultant tuning of concepts is not something that should be put aside when it comes to extrapolating from experience when evaluating extreme risks. On the contrary, is it a foundation that must be built on. It is the wide base of analogous cases that can compensate for the lack of data of directly relevant cases that is a feature of extreme risk analysis.

Friday, August 03, 2007

Reincarnation Only by Permission

A BBC report on the Tibetan Dalai Lama recounted (purported to recount?) that the Chinese Communist Party had proclaimed that reincarnation henceforth could occur only with the the permission of the Party.

Now that's temporal power!

Wednesday, August 01, 2007

Professor Larry Laudan Searches for Legal Epistemology and Can't Find It

I see that Prof. Larry Laudan wrote in Chapter 1 of his book Truth, Error, and Criminal Law, An Essay in Legal Epistemology (Cambridge University Press 2006):
The effort to answer that question constitutes what, in the subtitle of this book, I have called “legal epistemology.” Applied epistemology in general is the study of whether systems of investigation that purport to be seeking the truth are well engineered to lead to true beliefs about the world. Theorists of knowledge, as epistemologists are sometimes known, routinely examine truth-seeking practices like science and mathematics to find out whether they are capable of delivering the goods they seek.

Legal epistemology, by contrast, scarcely exists as a recognized area of inquiry. Despite the nearly universal acceptance of the premise that a criminal trial is a search for the truth about a crime, considerable uncertainty and confusion reign about whether the multiple rules of proof, evidence, and legal procedure that encumber a trial enhance or thwart the discovery of the truth. Worse, there has been precious little systematic study into the question of whether existing rules could be changed to enhance the likelihood that true verdicts would ensue. Legal epistemology, properly conceived, involves both a) the descriptive project of determining which existing rules promote and which thwart truth seeking and b) the normative one of proposing changes in existing rules to eliminate or modify those rules that turn out to be serious obstacles to finding the truth.

Gosh, I had the impression that the "new evidence scholarship" had something to do with epistemology. And this sort of evidence scholarship has been around for a while, for at least several decades. (It's no longer very new. Indeed, some observers said it was never very new -- that it has really been around since ca. the 17th century, and perhaps since Aristotle. Id.) But I guess I must be mistaken. Perhaps the so-called new evidence scholarship just isn't systematic enough to make into the pantheon of "legal epistemology"? Or perhaps it's not old enough to make the grade? I'll have to consult Jim Franklin about this.

Monday, July 30, 2007

Demeanor as Evidence

Prof. Laurie Levenson is publishing a promising-looking article on courtroom demeanor. Its subtitle is "The Theater of the Courtoom."

This topic -- the evidentiary status of the behavior of people in the courtroom -- is extraordinarily important (as Prof. Levenson fully recognizes) for both practical and theoretical reasons. The abstract of her article reads thus:

The American criminal courtroom is a theater where courtroom actors play out the guilt or innocence of the defendant for the jury to assess. Although one view of the courtroom is that of a controlled atmosphere where cases are decided based only on formal evidence, this view is undoubtedly unrealistic. Trials are affected by many factors, including the appearance and demeanor of the defendant. This article proposes an approach to deal with non-testifying demeanor evidence that occurs outside the witness box. Given the problems with having jurors rely on demeanor evidence, courts should be carefully monitoring the use of non-testifying demeanor evidence. Appropriate jury instructions should be given, including those warning jurors on proper use of such evidence.

Let's Not Give History Too Much Credit (or Blame): Thomas Davies on the Fifth Amendment Privilege against Self-Incrimination

Professor Thomas Y. Davies's recent attacks on the Supreme Court's view of the historical foundations of the Confrontation Clause are part of his broader campaign against the the Court's persistent misreading of history. In at least some of his published work Davies suggests that the Court's unwitting falsification of 18th century practices and understandings contributes to the trivialization of important constitutional rights and doctrines. In a 2003 article recently posted to SSRN, "Farther and Farther from the Original Fifth Amendment: The Recharacterization of the Right against Self-Incrimination as a 'Trial Right' in Chavez v. Martinez," 70 Tennesssee Law Review 987 (2003), Professor Davies concludes (foonotes omitted):
The point of this article is not that we should return to the original interpretation of the Fifth Amendment. That obviously is not feasible at this late date. Moreover, although the rigorously accusatory criminal procedure of the framing era may have been adequate for criminal justice in close communities, it would not be adequate for today’s mobile, urban society of strangers. There is a need for professional police and for proactive law enforcement and investigation; hence, police investigation, including interrogation, in some form, surely is here to stay.

Instead, my point is that assessments of the current status of the Fifth Amendment right should not proceed under the false notion that the current treatment of that right is equivalent to the right that the Framers intended to preserve. That false notion is deleterious because it tends to give an aura of inevitability to the current treatment of the right, and that aura tends to block critical appraisal of the choices that actually have shaped its content.

The authentic history of the Fifth Amendment right is a story of a right that has been shrunk by a drastic expansion of governmental criminal justice power, including governmental interrogation power. Moreover, that shrinkage has been permitted, to a large degree, because of the inattention and inaction of the Supreme Court. In particular, the Court initially failed to ask, or perhaps even perceive, the hard questions that were posed by the emergence of police interrogation as an unprecedented form of governmental interrogation. Despite the obvious danger of compelled self-incrimination in the backrooms of the police station, the Court failed to respond by developing a coherent view of what the Fifth Amendment right should mean regarding police interrogation. In addition, although the Miranda decision finally made a modest beginning in applying the Fifth Amendment right to impose conditions on custodial interrogation, even that regime of warnings and waiver has been undercut by more recent decisions. In fact, the opportunities for police interrogation of suspects have recently been expanded by decisions that have lowered the standard for taking suspects into custody, or that have permitted custodial arrests for minor offenses, even if such arrests amount to pretexts.

What is still necessary is for the Justices of the Supreme Court to take the question of what the Fifth Amendment right should mean today more seriously than they did in Chavez. At a minimum, the Justices should stop pretending that they are merely following the dictates of the text or original meaning of constitutional provisions when they are actually reinventing that text.

Regardless of what one might think of the claim for section 1983 damages in Chavez, deciding the question of whether there was a violation of the Fifth Amendment right merely on the basis of an acontextual, ahistorical, and essentially arbitrary definition of the word “case” in the 200-year-old text hardly constitutes meaningful constitutional interpretation.

The question that still needs to be addressed seriously and directly is what kind of police and criminal justice power is consistent with a free and civil society. Specifically, when is police interrogation compatible with a meaningful conception of a right against compelled self-accusation, and what conditions should be mandated when such interrogation is permitted? Whatever one might think of the appropriateness or efficacy of the specific regime of warnings and waiver that the Warren Court required in Miranda, that decision at least began to move—albeit haltingly—in the direction of addressing these crucial but long overlooked issues. The claim in Chavez, that the Fifth Amendment right is merely a trial right, is a large step in the opposite direction.

Sunday, July 29, 2007

Putin Defends Mass Murder

The man is candid. I'll give him that.

Entering Gulag (a leaf from Eufrosinia Kersnovskaya's notebook)

Source: Kersnovkaya foundation; Wikimedia Commons & GNU Free Documentation License


Tony Halpin, Textbooks rewrite history to fit Putin’s vision, Times OnLine (July 30, 2007):

***[T]he Kremlin is turning its attention to schools to instil a new sense of nationalism in children.

Two new manuals for teachers have been accused of glossing over the horrors of the Soviet Union and of including propaganda to promote Mr Putin’s vision of a strong state.


The [second] book describes Josef Stalin as “the most successful Soviet leader ever” and dismisses the prison labour camps and mass purges as a necessary part of his drive to make the country great. ***

Mr Putin gave [the books] his seal of approval at a conference he hosted for teachers at his presidential dacha last month. He described Stalin’s Great Purge of 1937, in which 1.5 million people were imprisoned and 700,000 killed, as terrible “but in other countries even worse things happened”. Discounting the Soviet Union’s long history of oppression, he said: “We had no other black pages, such as Nazism, for instance.”


Putin's assertion is roughly equivalent to saying, "We had to kill the country to save it." Or perhaps it amounts to the proposition that mass murder to promote fascism is bad but mass murder to promote communism (or nationalism) is o.k.

It used to be said in Hitler's defense that he built the Autobahnen.