Guardian article highlights observational biases in Knox investigators

[machrider]

Amanda Knox: What’s in a face?

Some choice quotes:

The eyes are not windows to the soul. They are organs for converting light into electro-magnetic impulses.

“We were able to establish guilt,” said Edgardo Giobbi, the lead investigator, “by closely observing the suspect’s psychological and behavioural reaction during the interrogation.”

There are several good insights throughout the article, many of which will probably seem familiar to readers of Less Wrong. The few that stood out to me:

1. Fundamental attribution error and the general tendency to create grossly oversimplified mental models of others (while simultaneously overestimating our model’s accuracy).

2. Various observational biases, especially egregious on the part of police and investigators. They were so satisfied with the “evidence” of her facial expressions, which is readily available (under the proverbial streetlight), that they felt this obviated the need for additional investigation. It appears that this led them to seek only evidence that further confirmed Knox’s guilt (confirmation bias), rather than considering ways to disprove the hypothesis.

3. Not sure what to call this other than the (not-too-well-established) Dunning-Kruger Effect: the tendency of nearly everyone involved to overestimate their ability to judge someone’s guilt based on expression reading techniques in which they may or may not be skilled.

[gjm]

The eyes are not windows to the soul. They are organs for converting light into electro-magnetic impulses.

Like komponisto, I loved this, but I can’t help feeling that if you’re going to engage in that sort of thing you ought to get it right. Light is already electromagnetic impulses, or at least electromagnetic waves; the eyes convert it into electrochemical impulses in the nerves and brain.

[komponisto]

You know, I thought the same thing. :-)

[[deleted]]

Interesting article, but my only concern is that it’s ever so easy to publish an analysis like that after Knox is found innocent.

Also, I found this book on body language by an FBI agent to be quite believable, and he claims to have used nonverbal communication successfully as a tool in his interrogations.

He downplays the idea that there is any particular body language associated with lying, which is unsurprising given evolutionary considerations. Most of the “tells” seemed to be related to people’s stress levels. He also claims that the face is the most misleading (i.e. under the person’s conscious control) aspect of someone’s nonverbal behaviours in comparison to the rest of their body.

Quote:

I look for pacifying behaviours in people to tell me when they are not at ease or when they are reacting negatively to something I have done or said

...

As a specfic example, if every time I ask a subject, “Do you know Mr. Hillman?” he responds, “No,” but then immediately touches his neck or mouth, I know he is pacifying to that specific question. I don’t know if he’s lying, because deception is notoriously difficult to detect. But I do know that he is bothered by the inquiry, so much so that he has to pacify himself after he hears it. This will prompt me to probe further into this area of inquiry.

So the eyes may be windows into the soul, but the hands and feet are more so. Looking for deception is the least promising approach. And the Italian investigators may not have been sufficiently skilled to interpret nonverbal signs properly, even if they hadn’t been irrational in numerous other ways.

[komponisto]

Interesting article, but my only concern is that it’s ever so easy to publish an analysis like that after Knox is found innocent.

There were plenty of similar articles published well before this week’s decision—including a number in the immediate aftermath of the guilty verdict two years ago. The dubious nature of the investigation—and in particular the focus on behavioral “evidence”—was never any secret.

And the Italian investigators may not have been sufficiently skilled to interpret nonverbal signs properly, even if they hadn’t been irrational in numerous other ways

Indeed, they seem to have completely misunderstood Amanda’s nonverbal signs. Their error is ironic, in that nonverbal signs (of both Amanda and those close to her) played a significant role in shaping my own view—since they contributed significantly to my surprise at the accusation, leading me to investigate the case in detail.

Evidently I was much more familiar with Amanda’s “personality type” than the investigators were.

[komponisto]

The eyes are not windows to the soul. They are organs for converting light into electro-magnetic impulses.

I loved this!

More:

What does it stem from, this over-confidence in facile intuitions about what other people are thinking? It probably has something to do with our innate difficulty in recognising that other people are as fully rounded and complex as we are. Emily Pronin, a psychologist at Princeton University, points out that there is a fundamental asymmetry about the way two human beings relate to one another in person. When you meet someone, there are at least two things more prominent in your mind than in theirs – your thoughts, and their face. As a result we tend to judge others on what we see, and ourselves by what we feel. Pronin calls this “the illusion of asymmetric insight”.

You know when you’re hiding your true thoughts and feelings – pretending to be fascinated by your boss’s endless anecdote, or grinning your way through an agonising first date – but you nonetheless tend to assume the other’s appearance tells the full story of how they feel: if she’s smiling, it’s because she’s genuinely enjoying herself.

Studies have found that people over-estimate how much they can learn from others in job interviews, while at the same time maintaining that others can only get a glimpse of them from such brief encounters. The model we seem to work with is something like this: I am infinitely subtle, complex and never quite what I seem; you are predictable and straightforward, an open book.