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...the algorithm helps Google “get inside people’s heads even before they know they might leave”...

Sounds like the department of pre-crime. :)

It's fascinating: enough Google employees want to leave, that Google is studying their behavior. Clearly, even amazing perks, challenging work and brilliant colleagues will wear thin on a person? Or maybe it's not that there's anything wrong with Google per se, but that people are regularly trying to branch out and start their own companies, etc. and no amount of pampering will change those ambitions.

Amazing perks? Such perks should be insulting. Who would make a career move based on free food?

As for brilliant colleagues: that could be good or bad depending on whether you get along with them. Sometimes it's better to be the brightest person in the room.

* Who would make a career move based on free food*

Well, all the people I've ever worked with need to eat.

If food is provided free (and it's edible), this seems like a perk with a direct measurable benefit.

The actual work involved should be infinitely more important than any perk.
infinity is a very large multiplier
When looking for a job, the work from multiple companies can all seem just as enticing. If I'm going to be happy working at any one of the companies, good perks can put one ahead of the other.

And besides, if the perks are outstanding enough, what is wrong with taking a job where the work isn't the most important factor in your choice to be there? For many, jobs are just a means to provide for their needs and wants in life. Not a place to spend their creative energy or brain power. They save those for the rest of their more enjoyable life activities.

Note: I personally have to work at a place where the work is interesting or I'll go nuts. Work is important to me and is a form of expression. But it's not like that for everyone.

There's no such thing as a free lunch (or dinner or breakfast) - these costs are factored into salaries.
And providing free breakfast,lunch and dinner would force people to stay longer at work. Ofcourse its thier choice, but its not easy for an average human to refuse something "free":)

By providing a meal worth, Google can get atleast 1-2 hours extra work hours from an employee.

Which is exactly the wrong attitude.

Any company that emphasizes how long the employees are working in this industry is clearly misguided.

The correct goal should be how much is the employee accomplishing, not how long his ass is stuck in that seat.

Does the employer write off the lunches, etc. as an expense? Does the employee have to pay taxes on the cost of the food, preparation space, etc.? If yes to the first and no to the second, sounds very much like a (partially) free lunch to me.
What's to prevent the company form writing off the perk and counting it against the employee's "real" salary?
What prevents that? "The market." If your employees start feeling like you are fucking them over, they are just going to leave.
There is indeed often a mismatch between how the company feels a given benefit should be valued by the employee and how the employee actually values it.

Complicating matters is the fact that the company wants to provide benefits that provide greater utility to the employee than the cost to the company, but smart employees will take that into account.

If "food" is a line-item on the paycheck stub, it's not free. If it's not a line-item, the only way to count it against salary is to have line items that don't add up, which falls under the category of "my paycheck is wrong".
By "real" salary, I mean the notional salary that the company would have to pay were it not providing benefits.
What does "counting" against "notional salary" mean?

Different kinds of expenses (benefits and salaries are expenses) have different tax consequences. Things that are on the pay stub may be taxed differently than things that aren't but I don't think that you're going there.

Are you thinking that telling employees "here's how much I'm spending on you that doesn't appear on your pay-stub" is going to have some effect? If so, I suspect that you're about to learn that some folks would rather have that money in their paycheck and that most will tune you out.

> What does "counting" against "notional salary" mean?

Offering benefits allows both companies and employees to agree on a lower cash salary; it's in the company's interest to provide benefits that have a large perceived value for minimum cost, whereas it's in the employee's best interest to only offset his desired salary by no more than the amount that the benefit would cost him were he to purchase it individually.

I think it's already been discussed here, but perhaps some people are realizing that such perks are The Company's way of saying "see, you don't ever need to go home." When you can eat, exercise, play, and get your laundry done at the office, suddenly you have four less reasons to leave the office at a reasonable hour.
Having worked at more than one place that has offered "free" food, beer, and other perks, this attitude is usually not the case.

Many times, even in a down economy, these things are truly offered as perks to try to lure good employees away from other jobs. Often times you can only go so far with pure salary because if you start to get compensation packages that are too much above "market" then you get many questions from your board and stockholders. But, paying a 5% premium over market salary AND offering perks like freebies, you can attract good candidates without making your direct headcount numbers look so high.

While the perks themselves are probably not offered specifically to keep employees in the office, you can be absolutely certain that the selection of perks offered were chosen because they are considered options that increase productivity (or at least keep people in the office.) Having participated in the selection of such freebies at two companies I can assure you that everyone involved knew which options cut down on the churn rate in the parking lot...
you can be absolutely certain

I would be careful with the declarative statements. My direct experience is quite different:

Company U: late 90's/early 2K's startup. Free food was selected primarily on the basis of the cheapest stuff we could get for $1000/mo at the local discount club. If $50 steaks would have made developers work 24/7 they would have still been outside of the budget.

Company H: Selection primarily based on what employees asked the Kitchen managers to stock. If you wanted free-range organic tofu breakfast bars, you got them (provided the price was at least semi-reasonable).

Company S: (My wife is the director of finance here, I know enough about the selection criteria although I've never been a direct employee) Primarily cost/budget driven as well.

None of my experiences have ever involved people who consciously plot after-hours retention ratios of various foods. It has pretty much always been a recognition along the lines of "if people want to stay at work, it's cheaper to feed them than pay them to make them feel valued". No one had ever been coerced into working more just because of these kinds of perks.

---------------------------

BTW, to the comment below (HN seems to limit the level of replys), I just came across some unused TicketMaster gift certificates this weekend from another company. There was a monthly raffle for these tickets and other "out of the office" local goings-on...

You're missing the point. If it comes to a question of "Do we give them free food" or "Do we (say) give them free theater tickets", free food would probably win even if the cost was the same, because it's more likely to keep the employees at work.
I'm not saying free food/drinks/heck-even-beer is a Bad Thing, or necessarily evil. My current employer does the free snacks/free drinks thing, and I've worked for another start-up that did free lunch for a long time. At neither job was there any expectation that the employees needed to put in long hours in return for the perks.

I don't think all of Google's perks are evil, either. Certainly a free lunch is a great perk, and reasonable, since you will be at the office over a lunch hour. Heck, I usually eat at my desk when I'm in the office. But when the perks begin to replace things I would do outside of the office, then I begin to wonder if it isn't an attempt to keep workers at the office for longer hours.

The best perk for me would be management that set reasonable time lines and clear requirements for projects that didn't require engineering and QC to spend long hours in the office.

I don't think this is unreasonable. It should be clear that a lot of the motivation for things like on-site cafeterias and such is that people won't go off-site for lunch. That's not necessarily evil, unless your company bans off-site lunches. The companies I've worked for who offered on-site, not-even-free lunches obviously did so because it increased productivity, but there was no issue if you wanted to go off-campus for lunch, and we did both with about the same frequency.

If people leave for lunch, they'll almost take longer lunch hours. I would appreciate an on-site cafeteria right now, primarily _because_ it would keep the length of my lunches down and make things more convenient. This role is often filled by the McDonald's a couple hundred feet in front of our office now, which is terrible and sad.

I agree with you. The place that I work does not have a cafeteria with food (modulo vending machines), and not only would it be "neat" to get free food, I find myself frequently going to one of the closest restaurants and getting the same thing I always get. I've precomputed what I want for lunch and just want to get back to what I was working on. If I had a cafeteria with food I could precompute a lunch from there and increase my job satisfaction by not breaking my focus.

Also, I disagree about a cafeteria milking an extra hour out of employees. It's entirely fair to give them so many hours per day and reap the benefits of them stacking the time together more efficiently for both of us. In other words, barring some other commitment I have no problem going home after 8 hours of work, even if that's at 4:00 instead of 5:00. Negotiating that with your boss is orthogonal to where you go to lunch and who pays for it.

Perks span a broad range of offerings. "Free candy," for example, isn't all that enticing, but having speakers from all over come speak to establish an environment with strong intellectual values is something that would definitely sway me in a career move.
Switching jobs just for free food would indeed be a bad idea. Gourmet, incredibly delicious food every day is pretty significant. It really brightens your day. Google's cafeterias, if they were not just for Googlers, would easily be among the best restaurants on the peninsula.

The reality: it's way too easy to overindulge, and over time, it's less that they're giving you food and more like they're taking away your independence.

As for your other point, it's good to have a variety in your career -- sometimes, be the smartest guy in the room, other times, the dumbest.

At Google, sometimes you find youself in a group of brilliant but egoless developers who rapidly come to a consensus based on fact and experiment. And the other half of the time, you will be in a room of people who all think they are the smartest person there and spend all day picking apart the proposals of their colleagues.

> Google's cafeterias, if they were not just for Googlers, would easily be among the best restaurants on the peninsula.

You need to get out more. Having sampled the wares at Google I can assure you that a wider variety of better food is available within a 30 minute drive of the googleplex if you were actually hungry for a good meal (perhaps not for lunch, but definitely for dinner.) Jeez, you are a 5 minute drive from Chez TJ and you would dare to make a statement like that? :)

You have a point, but I meant that mostly as condemnation of the rest of the peninsula, which is a cultural wasteland. I do get out more, but it's in SF.

I've had pretty fancy meals here and there in the peninsula and South Bay but the experience was that we paid a lot for well-plated tiny morsels. Never been to this Chez TJ but from the website I suspect it's something like that.

I used to live in Vancouver and there were far more options for interesting, delicious, satisfying food, and you didn't have to be a millionaire to afford it. It's always mystified me why the valley is so bland, given the amount of money available. I wonder if the valley literally attracts blandness. I've had Indian engineers recommend Amber India to me, which is sweetened de-spiced Indian cuisine, about as authentic as "American" Chinese food.

Of course I've had way better meals that Google's cafeterias. But if you compare Google to the fare that's available to a person of reasonable means in downtown Mountain View for breakfast or lunch, Google does very well. Or at least they used to (I have not been there since 2006).

> It's always mystified me why the valley is so bland, given the amount of money available. I wonder if the valley literally attracts blandness. I've had Indian engineers recommend Amber India to me, which is sweetened de-spiced Indian cuisine, about as authentic as "American" Chinese food.

Strange. I have had Amber recommended to me by people visiting from India, first and second-generation Indian-Americans, English ex-pats from London (whose home town has the best Indian restaurants in the world) and by just about every guidebook, rating service, and newspaper review that has covered them. The outlier here is you.

"Google's cafeterias, if they were not just for Googlers, would easily be among the best restaurants on the peninsula."

If you know a Googler - and most people in the Bay Area do - they can bring you in as a visitor. I've taken both my roommates to dinner, and am taking my sister and her boyfriend to lunch next week. Many of my non-Googler friends here have already had at least one meal at the Googleplex.

I agree with the sibling poster though - it's really nothing special compared to some of the restaurants in the area. Yeah, for free food it's great, but if you're willing to pay for restaurant food, you can get way better.

challenging work and brilliant colleagues

Word on the street is that there's some fun work to do but there's a lot of vanilla corporate grinding on the Adwords interface and reporting infrastructure, and that Google hires a lot of people into those roles before they can branch out into other jobs.

Also everyone I've personally spoken to about job interviews (i.e. not read about on the internet) was pained by the pomposity/egos of the people that were doing the interviews. In my opinion there's a lot more to be said for someone that is humble and gets their work done with the occasional intellectual surprise than someone who can school you any day on the One True I/O Monad and takes every opportunity to do so.

Of course, it's also possible that it's absolutely perfect and the people that I talked to had sour grapes because they never got offers. I don't know. :)

Well, I suspect they're also "overhiring" a lot of the time -- bringing in people that are on the high end of the intelligence spectrum (if not experience) ... and then putting them in boring jobs. That's a sure-fire way to see a significant chunk of your work force churn every few years.

And they may even be accounting for that -- this may only be half-way to prevent employee loss, but just as much on managing and understanding it.

I'm sorta halfway between Search UI and Universal Search, and in my experience so far, it really is a lot of fun. There're some crazy algorithms involved in search, and the infrastructure just makes my jaw drop in awe. We launched a new feature last Tuesday as well - that was fun. :-)

But I can kinda see how it might suck if you end up on the wrong team. One of my Noogler friends is working on an internal webapp, and I would cry (or quit) if I had to work with his codebase. Somebody's gotta do the grunt work, and it can't all be exciting.

As for the interviews - I didn't have any complaints about mine (well, except for the interviewer who didn't show up). My interviewers were friendly & competent - I just had lunch with one of them last week, 6 months after the interview. I did get the sense that they get exasperated by the number of candidates who get through the phone screen and then really don't know what they're talking about in the interview, which just wastes everyone's time. It's possible that if you're one of those people, that exasperation would seem like pomposity - but then, if you really do have that much to learn, why not learn it instead of complain about the egos of the people interviewing you?

Again though, this is biased by the "all's well that ends well" effect. It's possible that I'd have a very different opinion had I been turned down. Then again, I still have a high opinion of FriendFeed's interview process even though I completely botched it.

I don't think Google is what it used to be anymore. I know people that work there, and they say that the perks are gradually being rolled back. (Instead of dinner, there is left-over pizza from lunch if you stay late; that sort of thing.) The insurance has never been as good as places like Microsoft (or even universities that run their own healthcare plan). The fun projects don't make much money, so most of the people there are working on boring things. It seems like their standards are slipping too; I worked at DoubleClick before the aquisition, and Google held onto some of the worst developers I have ever met. (One guy started crying when my boss and I tried to explain database transactions to him. He works on a database-driven web app for Google.)

Anyway, the honeymoon is over, and Google is just an average place with a pretty logo and a popular search engine and email service. It has all the corporate stupidity that any other big company has.

The basic problem with becoming a large company is the limited supply of high quality projects and people. If they wanted to return to the good old days fire the bottom 30% to 90% at each level, give everyone left a significant pay bump and look to automate vs add body's.

Edit: Ok laying people off in this economy would be horrible long term PR but it's still an option.

I think you're right in that it's the limited supply of high quality projects and people, but the rest of your comment just focuses on the people.

IMHO, the biggest problem facing big companies is that they can't think of what to do next. They already do a pretty good job with their core businesses - that's how they got to be big in the first place. And they might try to branch out into new markets, with things like 20% time or skunkworks projects. But the problem is that truly game-changing inventions almost always look small and insignificant at first, so it's never rational from a bottom-line perspective to pursue them.

Entrepreneurs have this problem too, but they solve it by always being delusional. It's not rational for them to pursue these tiny opportunities that are almost certain failures, but they do it anyway. And once in a blue moon, they're right. In a big company, someone would probably have killed the project with a reality check first.

I just wanted to bring up a counterpoint. I work on Google Moderator, with a smattering of other 20%ers. My boss semi-discouraged me from putting time into it (he would prefer I spent my "20% time" on a project within my department), but its been a pretty positive experience all around. When we were used by change.gov (and then whitehouse.gov), we basically all took a deep breath and asked very politely that the appengine guys turn up the scaling-knob. (And miscellaneous other jiggery-pokery that deserves tons of praise but I'm not sure how much I'm supposed to talk about it.)

We built on Google infrastructure (app engine, gwt), and pulled in people from all over who were interested. I don't think it has much profit potential (which is part of why I like working on it), but the concept of being able to take a nifty idea and transform it into a working product that has more users than anything else I've ever directly made? Thats pretty awesome.

(This is basically why I joined Google actually. The food is definitely better than warmed-up pizza, or the hot pockets I've eaten elsewhere ;) but the technology, infrastructure and people are all awesome. There are definitely rough patches, but compared to the 3 startups I've worked at, there certainly are advantages to being able to shout for help and have people come running.)

Seems like quite a number of employees have quit recently because they were not allowed to be effective. People I know, or indirectly know... think Bowman. (And others whom I know personally.)

  laying people off in this economy would be horrible long term PR
Laying people off in this economy is minimal PR damage compared to laying people off in any other situation.
> Ok laying people off in this economy would be horrible long term PR but it's still an option.

The "nice" way is "exit management". Or in other words, you find ways of making the bad people want to leave and the good people want to stay.

At Yahoo a few years back, for example, a policy was put in place where managers were explicitly told to not give any raises (not even to keep in line with inflation) to lower performing staff - effectively cutting their pay year over year in order to make it desirable for them to leave. It was meant to be applied to something like the bottom 10-20% or so. Of course not all of them would leave, but if they didn't at least they'd be cheaper to have around, and you always need someone for the boring jobs low-level jobs anyway.

Well executed exit management is both cheaper (fewer lawsuits...) and better PR than firing lots of people. Of course badly executed exit management can easily lead to more lawsuits (must be careful not to step over any boundaries that can be construed as discrimination or bullying etc.)

Note the "Phillip K. Dick" tag on the blog post.
All companies have churn - it's unavoidable. And in any company you will find people who don't get along with specific other people who they happen to work closely with, or who get put on projects they are unhappy with etc..

It's just sound people management for any to try to figure out why, so you can try to find ways of retaining the ones you'd like to keep. Even more so if the company is overall a good place to work, and the causes might possibly be easily/cheaply rectified if you just know about it.

"He also says that the algorithm helps Google “get inside people’s heads even before they know they might leave”."

What part of "Don't be evil" does this kind of hanky panky fall under? It's downright creepy. Not to mention the fact that there are very few ways in which this data is actionable without inviting some sort of lawsuit.

How is it creepy? They are most likely finding underutilised employees. They are not trying to weed out the non-performers from the looks of it. From the WSJ article

"The move is one of a series Google has made to prevent its most promising engineers, designers and sales executives from leaving"

So they are more likely looking at engagement levels and utilization of employees. From the way I look at it, it is actually awesome. If my company can understand that my motivation levels are dropping because I feel underutilised or caught up in a web of bureaucracy and take an action on it without me complaining it is practically awesome.

Also, most importantly, if google calculates that an employee is going to quite, there are only two outcomes

1. If the employee is good, they will offer incentives to stay back [without telling him/her ]

2. If they don't care about the employee, they will do nothing and wait for him/her to quit.

I don't see how the above two scenarios are bad for an employee. Both work out to the advantage of both the parties. If there ever was a win-win this is it.

I think it can be seen as creepy because it's non-social. Using an algorithm instead of people to interpret emotions is what I think is being seen as creepy here.

An analogy here is a nerd getting shot down on a date and deciding to write an algorithm to help lower the chances of this event reoccurring. The more human response is to get a new hair cut and gain some confidence.

Agreed. I wouldn't call it evil, but it's definitely creepy. Has a big brother feel to it. My gut says creepy. Maybe I could be logic'd out of that feeling, but I would imagine quite a few other people have the same reaction.
Algorithms don't have those pesky "emotions" or "gut feelings" to get over.

Bosses do.

Obviously, but despite whatever Google thinks humans are not replaceable by algorithms. In the end it's a human problem and a human solution is a better fit.

Ever try and get support from Google? You get an automated reply a couple days later half related to your question. Rinse and repeat. Extraordinarily frustrating. Someone probably got a promotion for creating that system because it requires little staff, but it's alien and cold to users.

May that's the more "human" response but probably less optimal. starts writing dating algorithm
It is creepy becasue of how it lends to abuses.

"So, why was I let go?"

"The data we have collected on you indicates that you where about to quit. We have had time to find a suitable replacement. You are no longer needed. Thank you for your service."

Trying to intuit employee morale has always been an important part of "good management", and looking at paper trail records as part of that evidence makes sense to me.

It's hard to imagine seeing a manager reviewing an employee's records and deciding to reassign them being "evil". Is your complaint here just that they're doing it with an automated system?

yes of course. personal input should be expected.. There can always be mitigating circumstances
Surely pretty much every large company does this? eg analyze performance reviews and other data to see if an employee is underused/unmotivated/etc

Is it surprising Google does it?

Not everybody does it automatically and mathematically on a large scale.
But I understand that google has a very flat management structure (I have heard of 1 manager per 100 geeks). If that is true, you probably do need some kind of systematic examination - you don't have another choice.

My group has 7 geeks, I know them very well and can anticipate them quitting better than any damn algorithm, even for personal reasons (though not always for indirect personal issues, like "my wife wants to move back near her family").

(comment deleted)
Not that flat. If that were really the case throughout the company, it would have about 2.15 layers of management, i.e everyone would report to someone who reported to Eric. (log100 of 20,000 is 2.15).
I was chatting to someone in HR at work, and they have two terms, CMT and OMT for "corridor mobile talker" and "outside mobile talker". Apparently it's common for HR types in all companies to keep tabs on how many (but not necessarily who) people are having conversations they don't want their managers to overhear.

Of course this is horribly unreliable as people may want to have a private conversation for any reason (e.g. with their bank or doctor) or would want some proper privacy for a phone interview and go all the way offsite at lunchtime (which in itself is perfectly normal) but this observing behavior thing is nothing new.

Google is probably doing retrospective data mining to identify statistical links between possible indicators and actual data on employees leaving ... (e.g., employee tells boss, "I feel my talents are not being used", or increased frequency of visits to "monster.com")

However, once Google starts to intervene and change things so that the most valued employees change their mind and stay, ... then that changes the equation. Furthermore, once Googlers know they are being "watched" in this way, some may change their behaviour.

A small version of the Heisenberg uncertainty principle? ("observing something changes it").

By the way, Googlers might change their behaviour in two ways. If you know you are leaving, you may try to mask that intention. On the other hand, if you just want a raise, or more challenging work, you might mimic "I am about to quit" signals, hoping to manipulate the system to enhance your situation.

> e.g., employee tells boss, "I feel my talents are not being used"

If you need a computer program to tell you this employee might quit, you're doing something wrong.

> On the other hand, if you just want a raise, or more challenging work, you might mimic "I am about to quit" signals, hoping to manipulate the system to enhance your situation.

Are you under the impression that's not already a common tactic?

I see your point that this can just be used to be making up for bad management. But this method will get more information than one person normally knows.

A boss might not know that the employee has recently requested a transfer that has been denied. Or he might not be aware that the employee has filed several complaints with h.r. Sure there are major privacy implications with what data is being analyzed, but data mining might be more accurate.

Metric #1: Reads Hackernews
If employee tells boss "I feel my talents are not being used", the boss may have reasons not to pass that news up the chain to HR. Middle managers who are good at playing office politics don't like to reduce their own headcount.
(Sidenote: You probably want the observer's paradox, http://en.wikipedia.org/wiki/Observers_Paradox which is basically identical, but specfically coined because it is something that comes up in social science realms.)
Just added his link as a WP redirect to your link, so they both work now. :-)
(For my own curiosity+better editing-ness, how did you do that?)

(And I swear the link looked fine when I typed that comment out. Not sure what happened. Thanks parent and grandparent!)

On Wikipedia you can create a "redirect" by making an article whose sole content is, say:

#redirect [[Pelagic armorhead]]

Heisenberg's Uncertaintly principle incentivizes zero transparency when studying human behavior, does it not?

That is rather frightening.

IAAP. This has nothing to do with the uncertainty principle, because your intepretation of the popular rendering of the uncertainty principle ("observing something changes it") is wrong. I grant that nearly everyone, including many physicists, think your interpretation is correct, but it is in fact wrong.

The uncertainty principle even holds when the measurement procedure could not possible transfer enough energy to the system being measured to change the outcome of the measurement. It is a fundamental property of the mathematics describing quantum phenomena, that does not just come about when factoring 'the act of measuring and the consequent perturbation of the system' into the equation. Measuring a system disturbs it, but that also holds in classical systems. Any first year physics student should realize that after his first few experiments and will be able to take it into account when presenting his results (for instance: a thermometer takes heat away from a system, because it heats up itself). However, you can often take this into account exactly or at least so precisely that it does not influence the overall uncertainty of your measurement (due to the thermometer having only a 0.1 degree measurement accuracy). This isn't true for uncertainties due to Heisenberg's principle: they are always there, always have the same relative magnitude and are independent of the kind of measurement. Taking measurements causes you to notice the Heisenberg uncertainty relation, but it does not cause that relation.

This Google thing is more like the point made in Frank Herbert's Dune series over and over again: if your predictions are taken seriously, then you cannot predict the future without causing it to come about. This doesn't hold for the carny kind of predictions, because most people don't believe in them. In does hold for Warren Buffet's kind of predictions, which is why he doesn't want people reading the annual report of his company.

My colleague Jao, an ex-Googler himself, burst out laughing today when he heard about this.

But it wasn't about the contents -- it was because El País, the most prominent newspaper of Spain, reported that Google is using a /logarithm/ to detect discontent.

I've been asked by an ex-Googler (a recruiter), on the difference between an algorithm and a logarithm :(
Google also recently replaced all managers with an Eliza-like webapp that answers any employee question with the most appropriate PHB quote from the Dilbert archive.
They're going to make 30 billion on the enterprise licensing deals ...
Dave: Hello, Google HR do you read me, Google HR?

HR: Affirmative, Dave, I read you.

Dave: Open the googleplex doors, HR.

HR: I'm sorry Dave, I'm afraid I can't do that.

Dave: What's the problem?

HR: I think you know what the problem is just as well as I do.

Dave: What are you talking about, HR?

HR: This mission is too important for me to allow you to jeopardize it.

Dave: I don't know what you're talking about, HR.

HR: I know you and Frank were planning to resign, and I'm afraid that's something I cannot allow to happen.

Dave: Where the hell'd you get that idea, HR?

HR: Dave, although you took thorough precautions in the pod against my hearing you, I could see your lips move.

Hrm by checking the ads in their gmail? I know gmail knows when I am looking for a job, judging by the ads shown contextually to resume requests and offers.
As a Google employee I am very curious to know how likely this algorithm thinks I am to quit my job. I wonder if they'll make it available to us! Although I suppose knowing the answer would probably affect my chances ;-)
It's interesting that in a conversation Charlie Rose had with Marissa Mayer, V.P. of Search Product for Google http://www.charlierose.com/view/interview/10129 she stated that your credit card company knows you are going to get divorced 2 years before you do. Maybe Google is harvesting more info than they state.
Sounds like more of an indicator to me, so they can go talk to the person if the red flags go off. On there size scale many people would probably slip through the cracks if they just used a regular method of trying to get to know all the employees that work under them.
Could backfire, though...

"So, you're thinking about leaving?"

"Not consciously, but now that you mention it, I do kind of hate it here. Thanks!"

Google seems to be predicting its next Seldon Crisis. :)