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Comment by tsunamifury | Hacker News Reader

What a tragedy of justice that you used an absence of evidence as a deciding factor. There is so much logically wrong with that, even in correlation.

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Suppose somebody's alibi is "I was driving between these two cities at the time, and then I spent the night working."

But their car-odometer didn't change, and their home-electricity usage dropped to zero that day.

Both of those observations are surely "evidence". Similarly, a digital signal still carries information, even though the zeroes are an "absence" of voltage.

Thats a lot different from "you weren't talking to someone, so you must have been doing X" Whereas in real life X could = anything.

The logic isn't even close:

Odometers increment on driven cars. The odometer did not increment. The car was driven. Unsatisfied.

People having sex are together. People who are together don't text each other. During a certain hour a person didn't text 68 contacts. At this certain hour, this certain person had sex with 68 people. Satisfiable.

It's more like: these two numbers are in constant contact all other hours of the day. At this hour midday, when others, including one of the relevant parties, say those two numbers are together, there is no correspondence. Later, the correspondence picks up as before.

I see your point of high probability they might have been together. But I don't see evidence for "sexual misconduct" during the time they were together. They could have just talked.

Anyway, the whole charge is disgusting. Leave them alone dammit.

You seem to be aware, at least on a subconscious level, of the larger point - as you've demonstrated by including additional evidence. The larger point being that the absence of phone records can, at best, disconfirm. There are far too many alternative explanations for it to be used alone or as confirmation.

Remember, in court we're not talking about logical proof (eliminating every alternative but the desired conclusion), but statistical proof (eliminating alternative conclusions with 51% or 95% certainty). Given an assumed or established statistical model of the probability of related events (e.g. knowing that a secretary at a business makes a log entry 99.9% of the time when she sends out a mailing), a non-happening (say the absence of a log entry) can easily establish a conclusion to the desired level of certainty.

Darn, I already replied to this point moments ago. There is a difference in the application of this logic in the court room where it can be challenged, and the juror room where it cannot - right?

There is nothing logically wrong with that. Evidence is anything that makes a conclusion more or less likely (in the Bayesian sense). All else being equal, knowing of a gap in an otherwise constant stream of communication makes a in-person meet-up more likely than it is without that knowledge.

Not every piece of evidence (in the Bayesian sense) is admissible in every court though, polygraphs being an obvious example. That is why courts get all pissy when jurors go off the reservation and start doing their own research. I'd be a little surprised if the judge in this case enthusiastically endorsed this sort of analysis going on in jury deliberation, but given your background - I'm interested to hear if I'm mistaken.

Evidence can be excluded if it's not relevant (in the Bayesian sense), or unreliable. You might have some argument that the phone records don't make the conclusion sufficiently more likely to warrant admitting it. But the bar for relevance is not high.

Moreover, this is kind of what juries do best: inferring what people did from other things they did or didn't do. While juries are subject to a lot of biases, I think humans have a good statistical model of the behaviors of other humans.

I guess I've been mistaken in my understanding of the whole process. I was under the impression that all the controls are in place specifically to restrict the juror's natural inclination to infer, because humans really suck at logical inference (and not just because of bias). I'd always assumed that an an innovation in natural language processing and combination with formal logic would be welcome in the court room, but it doesn't sound like that would be the case if empiricism is preferred to rationality.

This is just not true -- there are tons of highly informative, relevant kinds of Bayesian evidence that are excluded. For example, remaining silent, illegally-obtained evidence, hearsay, opinion of experts (in many cases).

The evidence is the phone record with a string of calls. A gap between calls is as much evidence as a phone call is. A gap is not absence of evidence.

What would you have used as a deciding factor? Often times circumstantial evidence is all there is to work with.

A case built on circumstantial evidence is the very definition of reasonable doubt and should be tossed out! I don't understand why so many people think the purpose of court is to convict people! You're question could litterally be reduced to "But how are we supposed to find them guilty if we don't have evidence?"

Ultimately, what is "reasonable doubt" is up to the jury.

I can't say I agree with the use of circumstantial evidence, but that's how the court works. Additionally, many people do get off based on lack of clear evidence?

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