Citeren Bruno Marchal <>:

On 08 Oct 2013, at 22:22, wrote:

Citeren Craig Weinberg <>:

*Humans 1, Robots 0*
Cashiers Trump Self-Checkout Machines at the Grocery Store

Computers seem to be replacing humans across many industries, and we're all
getting very nervous.

But if you want some reason for optimism, visit your local supermarket. See that self-checkout machine? It doesn't hold a candle to the humans-- and its
deficiencies neatly illustrate the limits of computers' abilities  to mimic
human skills.

The human supermarket checker is superior to the self-checkout  machine in
almost every way. The human is faster. The human has a more  pleasing, less
buggy interface. The human doesn't expect me to remember or look up  codes
for produce, she bags my groceries, and unlike the machine, she  isn't on
hair-trigger alert for any sign that I might be trying to steal  toilet
paper. Best of all, the human does all the work while I'm allowed  to stand
there and stupidly stare at my phone, which is my natural state of  being.

There is only one problem with human checkers: They're in short  supply. At
my neighborhood big-box suburban supermarket, the lines for human  checkers
are often three or four deep, while the self-checkout queue is  usually
sparse. Customers who are new to self-checkout might take their short lines
to mean that the machines are more efficient than the humans, but  that
would be a gross misunderstanding.

As far as I can tell, the self-checkout lines are short only  because the
machines aren't very good.

They work well enough in a pinch--when you want to check out just a handful
of items, when you don't have much produce, when you aren't loaded  down
with coupons. But for any standard order, they're a big pain.  Perversely,
then, self-checkout machines' shortcomings are their best feature:  because
they're useless for most orders, their lines are shorter, making the
machines seem faster than humans.

In most instances where I'm presented with a machine instead of a  human, I
rejoice. I prefer an ATM to a flesh-and-blood banker, and I find  airport
check-in machines more efficient than the unsmiling guy at the  desk. But
both these tasks--along with more routine computerized skills like  robotic
assembly lines--share a common feature: They're very narrow,  specific,
repeatable problems, ones that require little physical labor and  not much
cognitive flexibility.

Supermarket checkout--a low-wage job that doesn't require much
training--sounds like it should be similarly vulnerable to robotic invasion.
But it turns out that checking out groceries requires just enough
mental-processing skills to be a prohibitive challenge for  computers. In
that way, supermarket checkout represents a class of jobs that  computers
can't yet match because, for now, they're just not very good  substituting
key human abilities.

What's so cognitively demanding about supermarket checkout? I spoke  to
several former checkout people, and they all pointed to the same  skill:
Identifying fruits and vegetables. Some supermarket produce is  tagged with
small stickers carrying product-lookup codes, but a lot of stuff  isn't.
It's the human checker's job to tell the difference between green  leaf
lettuce and green bell peppers, and then to remember the proper code.

"It took me about three or four weeks to get to the point where I  wouldn't
have to look up most items that came by," said Sam Orme, a 30-year- old grad
student who worked as a checker when he was a teenager.

Another one-time checker, Ken Haskell, explained that even after  months of
doing the job, he would often get stumped. "Every once in a while I'd get a
papaya or a mango and I'd have to reach for the book," he said.

In a recent research paper called "Dancing With Robots," the  economists
Frank Levy and Richard Murnane point out that computers replace human
workers only when machines meet two key conditions. First, the  information
necessary to carry out the task must be put in a form that  computers can
understand, and second, the job must be routine enough that it can be
expressed in a series of rules.

Supermarket checkout machines meet the second of these conditions, but they fail on the first. They lack proper information to do the job a human would
do. To put it another way: They can't tell shiitakes from Shinola.  Instead
of identifying your produce, the machine asks you, the customer, to type in
a code for every leafy green in your cart. Many times you'll have  to look
up the code in an on-screen directory. If a human checker asked you  to
remind him what that bunch of the oblong yellow fruit in your  basket was,
you'd ask to see his boss.

This deficiency extends far beyond the checkout lane.

"In the '60s people assumed you'd be reading X-rays and CT scans by
computers within years," Mr. Levy said. "But it's nowhere near  anything
like that. You have certain computerized enhancements for simple  images,
but nothing like a real CT scan can be read by a computer--and the  same
thing would be true trying to separate arugula from everything else."

You could imagine certain ways to make the identification process  easier
for supermarket computers. For example, we could tag every produce  item
with an electronic identification tag. But that would be an enormous
infrastructural challenge for a dubious return.

A representative for NCR, the world's largest self-checkout vendor, pointed
me to a company-sponsored survey that shows that customers believe
self-checkout systems are faster than cashier lanes. But I doubt  those
perceptions. When you actually watch self-checkout lanes matched up against cashiers, the cashiers come out significantly faster--read this Ph.D. thesis
for proof, or go to your local store and marvel at how speedy the  humans

Can computers beat them? Perhaps one day, but I doubt it will be  soon. And
that gets to the other issue: Unless the store gives me an explicit  price
break for scanning my stuff, why, exactly, should I be rejoicing  about
doing more work?


A lot of what I am always talking about is in there...computers don't
understand produce because they have no aesthetic sensibility. A mechanical
description of a function is not the same thing as participating in  an


You can't expect a machine with the computational capabilities of less than an insect brain to the job most people do. It's actually amazing that such machines can do quite a lot, but some tasks we perform are the result of a significant part of our brain power.

Craig, like xenophobes, do this repeatedly. To generalize invalidly from particular cases. That some x is stupid does not entail that all x have to be stupid.


What also plays a role here is that people tend to underestimate just how complex the human brain is. We are confronted on a daily basis with the misleading fact that simple devices like calculators can outperform us.

We don't realize just how much preprocesing the brain does at the subconscious level. Also when we try to do mental airthmetic like 12*53, then we do that in an enormously inefficient way. It's like using a pc that only has a word processor installed and you then do that calculation by using the word count facility. But just to run that word processor requires way more complex manipulations than evaluating 12*53.

I've had similar discussions with people who believe in paranormal phenomena. Some people can be quite good at using their intuition to sense things. But when testing under rigorous controlled circumstances they fail. But the believers will still argue that there must be some paranormal effect here because "they can't see how he/she comes up with that information". But then if you could give a simple formal explanation that explains this, e.g. how to look at someone's face to extract the desired information, then you could also do this task using a programmable calculator, which means that an insect should in principle also be able to perform that task. But we obviously don't have a vastly larger brain than that of an insect for nothing.


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