
Walmart employees are out to show its anti-shoplifting AI doesn’t work - pseudolus
https://arstechnica.com/tech-policy/2020/05/walmart-employees-are-out-to-show-its-anti-shoplifting-ai-doesnt-work/
======
SkyBelow
There is a lot of information in the article but little to draw a conclusion
from. They bring up examples where the AI failed, but that alone does not
indicate it doesn't work.

An AI that fails to recognize some thefts but does recognize others can still
be considered to work as long as enough thefts are caught. Imperfect, but
given the low cost of a failure relative to not using an AI, imperfection
seems quite tolerable. Even the false positives seem to be of little concern
as they involve a shopping associate coming over and having to assist an
individual. As long as the experience for the shopper remains more pleasant
than waiting in line for one of the cashier operated checkouts, it is still an
overall win.

So yes, the AI is imperfect, but where is the information that justifies the
conclusion it doesn't work and not the conclusion that it doesn't work
perfectly?

~~~
birdyrooster
They must have forgotten the name of the game is loss prevention for the
business and not about stopping shoplifting. Cutting payroll on your loss
prevention is loss prevention in of itself.

~~~
pscoutou
I’m not sure. When self-checkouts were introduced here, they had staff
supervising to help and educate customers then significantly scaled back that
headcount.

Fast forward several years, there’s more staff stationed with self-checkout
due to theft.

I think retailers are going to calculate the cost of headcount and theft and
make a decision based on an equilibrium.

Of course, the best outcome for Walmart is to have an automated LP system to
reduce staffing cost for the long term.

~~~
sukilot
Self checkout has 1/2 to 1/8 the staff of full checkout.

~~~
pscoutou
In my example, big grocery chains here had 5-6 employees at launch then
dropped it to just one.

Now they have 2-3 employees monitoring the self checkout.

There is a certain point where employers become more focused on reducing
shrinkage than headcount.

~~~
throwawaygh
If they’re open 24/7/365, that’s still six figures in savings. And if one of
those employees is watching the self checkouts then losses might not even be
that much higher. And that with 90s technology — very little/no CV. I think
Cashier as a stand-alone job will probably die off in our lifetime. Maybe you
still have a store manager who is up at the front of the store whenever they
are not doing something else.

(I’ve been a cashier at a grocery store)

------
49531
As someone who has inadvertently stolen from Walmart on more than one
occasion, I cant attest that their anti-shoplifting AI does not work.

~~~
ggreer
How does one inadvertently steal?

~~~
jedberg
If you have kids it's really easy. You don't notice that they put an item in
their stroller or inside another item that you're buying (like you're buying a
cooler and they put a toy in the cooler).

Technically it's your kids stealing, but since you are responsible for their
actions, it's on you.

When this happens to me I usually let them know the next time I'm at that
store (or if I discover it in the parking lot I go back in). Sometimes they
charge me for it, usually they just say thanks for being honest.

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code4tee
This is a very hard problem and thinking a product could do this without
extremely high error rates is naive.

Any implementation should use this as a supplement only, not replacement for
humans. For example a human watching 10 checkouts and quickly manually
reviewing scenes flagged as suspicious. Any implementation should also account
for the fact that loss will still occur and account for that in the RoI.

The fact that the technology is very error prone is not surprising (to anyone
that actually builds AI tech). The issue here sounds like poor implementation
and unrealistic expectations from management on what AI truly can and can’t
do.

~~~
sergiosgc
Preventing scanning one item and placing two on the bag? It's an easy problem.
Just have scanned items be placed on a scale. People will be bagging stuff to
take home, so just have bags placed on a scale and observe the weight increase
as items are placed in the bag.

You probably know the weight of one jug of milk, but even if you don't, it's
easy to "learn" the weights of new SKUs statistically.

~~~
lolinder
Early self-check kiosks did this very poorly. It was super frustrating as a
customer to be constantly asked to "please place the item in the bagging
area", even when I already had, not to mention the hassle it caused when
buying something you don't want to bag. Eventually I'm assuming they gave up
on that and turned it off.

~~~
nicoburns
Checkouts in the UK still do this. They just seem to have gotten better at it,
so I rarely have problems anymore. Possibly they loosened the tolerances.

~~~
lukeramsden
Still pisses me off endlessly though, I'm only scanning a couple items that
are going right in to my backpack. Takes 3x the time because of those stupid
scales.

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dx87
I'm suprised they even bother to try and stop it. My grandfather works at
WalMart, and said that they're told to not try and stop shoplifting because
they don't want customers to be afraid to shop there.

~~~
karatestomp
Some around here hassle people for their receipts near the exit. It was
already my least-favorite place to shop for a ton of reasons, so that was
enough to stop me ever going. It's one thing at Costco where I agreed to it
and they're very fast and nice. I'm not standing in line to get permission to
leave friggin' Wal-Mart (yes I know you can just ignore them but they
sometimes try to stop you and make a big deal of it and that's just not a
situation I want in my day)

~~~
Terretta
Also Best Buy, which is particularly annoying as they watch you check out at
the register five or ten feet from their post, then "randomly" (almost always)
demand the receipt.

Who are you checking, the cashier or the buyer? My guess is a deterrent for
some kind of collusion.

~~~
logfromblammo
Change of ownership happens at the point of sale. Toss them a cheery "no,
thanks," and walk on by. They have no authority to detain you.

Same with Fry's. Not the same with Costco; there, you're subject to the
membership agreements.

~~~
cgriswald
They do have the authority to prevent you from returning to the store. This is
the only reason I ever agreed at Fry’s.

At Best Buy I stopped shopping there for years. I don’t remember why I
eventually went in one again, but in the years since I’ve never been asked
once. I do wish they’d get rid of the guy at the door entirely. It’s weird.
And they always greet you from the side or back.

~~~
logfromblammo
Sounds like a good reason to show your receipt... at the returns counter.

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dkdk8283
My local walmart now has cameras getting your face at self checkout. I cover
it with a bag before using checkout

~~~
jedberg
If it bothers you so much, why not just use the regular checkout? Or just shop
somewhere else? Do you cover their security cameras all around the store with
bags or just the self-checkout one?

This seems a really odd place to draw the line on surveillance.

~~~
heavyset_go
I've noticed that some stores put cameras behind cashiers such that they point
at both the cashier and the customer.

~~~
teachrdan
A lot of these cameras are intended to primarily capture the cashier, to
prevent them from stealing cash from the till.

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49531
While not super related, I've always been fascinated by shoplifter analysis of
loss prevention you can find on the internet:
[https://raddle.me/wiki/shopliftingml](https://raddle.me/wiki/shopliftingml)

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nabnob
Is it just me or do the "Concerned Home Office Associates" not sound like they
actually work at Walmart? I talk to the workers at my local Walmart and they
don't refer to themselves as "associates", or care enough about a minimum wage
job to contact media over anti-shoplifting AI failing.

~~~
mountainboot
I bet they do. "Home Office Associate" means office worker or manager. A
programmer falls under this. It isn't a minimum wage "store associate". Of
course they won't refer to themselves as store associate when casually
chatting to a shopper.

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m0zg
And that is why such technologies are best deployed with humans in the loop.
Tech flags, human checks, human label is fed back into training. Fewer humans
will be needed now, even fewer 2-3 years from now. There are literally tens
(if not hundreds) of thousands of people every day doing nothing but watching
security feeds. And 99% of the time nothing is going on.

------
yencabulator
Walmart self-checkout is the second best working self checkout I've used so
far. (The best one is Sam's Club: you scan things with your phone as you put
them in the cart, and when you're done you tap checkout and leave the store.
Payment happens in the phone app.)

If the cost of having self-checkout machines that actually _work_ and let you
complete your purchase is that some items slip by, that might well be worth
it.

In contrast, Safeway chain self-checkouts are such a miserable experience that
for more than two items, even waiting in a long cashier line is worth it.
Their system requires you to place every purchased item on a scale after the
scan, and a good fraction of the time the scale fails to read the expected
added weight, forcing you to wait for staff to unlock the machine again. For a
cart full of purchases, this will happen half a dozen times.

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crazygringo
I mean, presumably Wal-Mart has excellent statistics on "shrinkage" from
regular inventory checks like any store, as well as recording how often
shoplifters are caught, and so they have clear data as to whether or not
Everseen is an improvement or not.

And I don't understand what this has to do with COVID-19 at all in the
article.

Finally, what do _employees_ care about theft? It's not coming out of their
paycheck. False positives from an anti-theft system seems like a small job
nuisance at best -- not something to whistleblow with a "slickly produced
video".

Nothing about this article makes sense to me, unless it's motivated by an
Everseen competitor -- whether another company or an internal division of Wal-
Mart that thinks they have a better solution. In either case, why would the
general public care at all?

~~~
barbecue_sauce
Employees are often the ones accused of theft?

~~~
ADent
When I worked retail, employee theft was the big deal. From pocketing cash to
a dock guy bringing up stuff for his buddies during busy times to the Theft
Prevention team doing something to all get fired I think the employees did
more damage than the shoplifters.

We didn’t have self checkout back then, though.

------
Shivetya
self check out systems are great and the concerns of the workers should be
heard but it comes down to not having all the numbers.

what is the positive to false positive rate? projects can have metrics that
those in the field are not privy too and it could down to they are preventing
a sufficient dollar amount to not consider the false positives are an issue.
Again, what are the percentages?

~~~
throwawaygh
Right. It takes _a lot_ of theft to pay for a whole extra human standing
there. Even a minimum wage.

~~~
logfromblammo
See also farmers' produce stands that are often completely unmanned and run
100% on the honor system.

People take fruit and vegetables, and put the money in the box--or if the
farmer is tech-savvy enough, through their phones. And even if a few people
don't pay, they still get more money from their inventory than shipping it to
a wholesaler or a grocery store. (As far as I know, direct to a local gourmet
restaurant pays best.)

For an extra employee on the duty roster, you're probably paying minimum $7
per hour, every hour that store is open to the public--probably 16 hours a
day, every day, for a big box. That's $41k per year, plus the per-employee
costs for 2 or 3 people, which are probably another $60k, unless you're an
employer that doesn't offer benefits (i.e. Wal-Mart).

The employee would likely have to stop $200/day of petty theft. That doesn't
seem impossible, but the problem is that if you pay your employee minimum
wage, they don't actually _care_ that people are stealing from their employer,
because they have no actual incentive to do anything beyond what is the bare
minimum requirement to avoid getting fired, which may be just catching _one_
shoplifter per day.

And then, after all, if one caught _every_ shoplifter, _every_ day, people
would stop trying, and one might miss quota on later days. The person whose
job depends on shoplifters has a perverse incentive to encourage shoplifting,
just as cobra-catchers have an incentive to breed and release snakes.

So the problem is more that it's too expensive to hire someone at a rate high
enough to make them _care_ about doing their job well, instead of just keeping
it indefinitely while gaming the right metrics.

~~~
Melting_Harps
> People take fruit and vegetables, and put the money in the box--or if the
> farmer is tech-savvy enough, through their phones. And even if a few people
> don't pay, they still get more money from their inventory than shipping it
> to a wholesaler or a grocery store. _(As far as I know, direct to a local
> gourmet restaurant pays best.)_

It does.

> The employee would likely have to stop $200/day of petty theft. That doesn't
> seem impossible, but the problem is that if you pay your employee minimum
> wage, they don't actually care that people are stealing from their employer,
> because they have no actual incentive to do anything beyond what is the bare
> minimum requirement to avoid getting fired, which may be just catching one
> shoplifter per day.

> And then, after all, if one caught every shoplifter, every day, people would
> stop trying, and one might miss quota on later days. The person whose job
> depends on shoplifters has a perverse incentive to encourage shoplifting,
> just as cobra-catchers have an incentive to breed and release snakes.

You just explained the the broken window type fallacy of LEO and Police in
general. When the crime no longer exists, you create it... by force. Oddly
enough, it also applies to loss prevention.

> So the problem is more that it's too expensive to hire someone at a rate
> high enough to make them care about doing their job well, instead of just
> keeping it indefinitely while gaming the right metrics.

Agreed. And again, it applies to more than just shoplifting prevention.

~~~
logfromblammo
For those not familiar with why cobras were mentioned above:

[https://en.wikipedia.org/wiki/Cobra_effect](https://en.wikipedia.org/wiki/Cobra_effect)

Long story shortened:

    
    
      1. British are ruling India
      2. Concern about cobras
      3. Establish dead cobra bounty
      4. Cobra population crashes
      5. Entrepreneurs breed cobras
      6. Bounty program halted
      7. Breeders release stocks
      8. More cobras than before
    

The source story is just an anecdote, but there are plenty of historically
verifiable examples of the effect, not necessarily involving cobras,
specifically.

------
nojito
False Positives don't matter. It's all about mitigating False negatives enough
to lower shrinkage and justify the costs of the software.

~~~
sudosysgen
False positives may cost more than the items being protected in diverse costs.

~~~
duxup
It seems that the self service kiosk just stops functioning if it thinks
something is wrong.

I'm not sure how many high intensity "you're stealing!" confrontations really
occur.

~~~
jschwartzi
It should really allow you to continue scanning but prevent you from paying
until the associate confirms that you're not stealing. That's 90% of the issue
with the weight sensors -- the sensor stops me from moving forward with other
purchases because it's making me wait for someone to check my stuff. But if
they left the notification on while I continued to scan that would eliminate
my issues with it entirely. Then they wouldn't need to rely on flaky AI.

The other issue I have is that the barcode scanners are not activated until
the weight sensor settles out, which can take several seconds up to a minute,
so it's way slower than going to a checker. If the weight sensor didn't gate
barcode scanner activation I would have a much better experience.

All they really need to do is verify the weight of the total transaction and
have the associate check on any discrepancies. And they can probably use a
very noisy weight signal with a low-pass filter. They don't need to blow a ton
of money on an AI solution that is about the same level of inconvenient.

If I had 10 or 20 million dollars I'd build a better self-checkout.

~~~
somehnguy
The self checkouts at my local Walmarts already do this. When an error occurs
it flags for help but lets me proceed up until it is time to pay. By then
usually an associate has already made their way over to check the errors in
batch vs 1 at a time as they come up.

It's so much nicer of an experience compared to machines that just stop
functioning until an employee can "help" you.

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sys_64738
Hire more humans. Problem solved.

~~~
matz1
Not quite simple, human are expensive and finicky.

~~~
macintux
And employees in any retail establishment are prone to shoplifting, so adding
more might not help.

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adameast1978
So, I didn't read the article but if these employees didn't want to be
replaced by API they could theoretically be helping the AI team find
weaknesses in system and improve the system even more quickly.

~~~
ghostbrainalpha
Not really.

Their job isn't to "identify" the shoplifting, but deal with the consequences
and shoplifter after it has been identified.

So if the A.I. get's better, then they harass less innocent people, and the
humans job gets better.

The employees job will be at greater risk when Walmart goes full ROBOCOP.

------
mnm1
Walmart are scumbags who will pursue shoplifting charges with no evidence and
try to collect from innocent people. [1] I'm not surprised they are using AI
for this, a system that's bound to cause false positives. It should be illegal
for them to make such accusations and take up the court's and the defendant's
time, money, resources, and freedom. False accusations should carry heavy
penalties. Instead, they carry no penalties. Once again, another instance
where the average person will get fucked over with no recourse.

[1] [https://www.nytimes.com/2018/08/17/business/falsely-
accused-...](https://www.nytimes.com/2018/08/17/business/falsely-accused-of-
shoplifting-but-retailers-demand-they-pay.html)

