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Ya’ make your own luck, n’est-ce pas?

This is a guest post by Leopold Dilg.

There’s little chance we can underestimate our American virtues, since our overlords so seldom miss an opportunity to point them out.  A case in point – in fact, le plus grand du genre, though my fingers tremble as I type that French expression, for reasons I’ll explain soon enough – is the Cadillac commercial that interrupted the broadcast of the Olympics every few minutes.

A masterpiece of casting and directing and location scouting, the ad follows a middle-aged man, muscular enough but not too proud to show a little paunch – manifestly a Master of the Universe – strutting around his chillingly modernist $10 million vacation house (or is it his first or fifth home? no matter), every pore oozing the manly, smirky bearing that sent Republican country-club women swooning over W.

It starts with Our Hero, viewed from the back, staring down his infinity pool.   He pivots and stares down the viewer.  He shows himself to be one of the more philosophical species of the MotU genus.  “Why do we work so hard?” he puzzles. “For this?  For stuff?….”  We’re thrown off balance:  Will this son of Goldman Sachs go all Walden Pond on us?  Fat chance.

Now, still barefooted in his shorts and polo shirt, he’s prowling his sleak living room (his two daughters and stay-at-home wife passively reading their magazines and ignoring the camera, props in his world no less than his unused pool and The Car yet to be seen) spitting bile at those foreign pansies who “stop by the café” after work and “take August off!….OFF!”  Those French will stop at nothing.

“Why aren’t YOU like that,” he says, again staring us down and we yield to the intimidation.  (Well gee, sir, of course I’m not.  Who wants a month off?  Not me, absolutely, no way.)  “Why aren’t WE like that” he continues – an irresistible demand for totalizing merger.   He’s got us now, we’re goose-stepping around the TV, chanting “USA! USA! No Augusts off! No Augusts off!”

No, he sneers, we’re “crazy, hardworking believers.”  But those Frogs – the weaklings who called for a double-check about the WMDs before we Americans blasted Iraqi children to smithereens (woops, someone forgot to tell McDonalds, the official restaurant of the U.S. Olympic team, about the Freedom Fries thing; the offensive French Fries are THERE, right in our faces in the very next commercial, when the athletes bite gold medals and the awe-struck audience bites chicken nuggets, the Lunch of Champions) – might well think we’re “nuts.”

“Whatever,” he shrugs, end of discussion, who cares what they think.  “Were the Wright Brothers insane?  Bill Gates?  Les Paul?…  ALI?”  He’s got us off-balance again – gee, after all, we DO kinda like Les Paul’s guitar, and we REALLY like Ali.

Of course!  Never in a million years would the hip jazz guitarist insist on taking an August holiday.  And the imprisoned-for-draft-dodging boxer couldn’t possibly side with the café-loafers on the WMD thing.  Gee, or maybe…. But our MotU leaves us no time for stray dissenting thoughts.  Throwing lunar dust in our eyes, he discloses that WE were the ones who landed on the moon.  “And you know what we got?” Oh my god, that X-ray stare again, I can’t look away.  “BORED.   So we left.” YEAH, we’re chanting and goose-stepping again, “USA! USA!  We got bored!  We got bored!”

Gosh, I think maybe I DID see Buzz Aldrin drumming his fingers on the lunar module and looking at his watch.  “But…” – he’s now heading into his bedroom, but first another stare, and pointing to the ceiling – “…we got a car up there, and left the keys in it.  You know why? Because WE’re the only ones goin’ back up there, THAT’s why.” YES! YES! Of COURSE! HE’S going back to the moon, I’M going back to the moon, YOU’RE going back to the moon, WE’RE ALL going back to the moon. EVERYONE WITH A U.S. PASSPORT is going back to the moon!!

Damn, if only the NASA budget wasn’t cut after all that looting by the Wall Street boys to pay for their $10 million vacation homes, WE’D all be going to get the keys and turn the ignition on the rover that’s been sitting 45 years in the lunar garage waiting for us.   But again – he must be reading our mind – he’s leaving us no time for dissent, he pops immediately out of his bedroom in his $12,000 suit, gives us the evil eye again, yanks us from the edge of complaint with a sharp, “But I digress!” and besides he’s got us distracted with the best tailoring we’ve ever seen.

Finally, he’s out in the driveway, making his way to the shiny car that’ll carry him to lower Manhattan.  (But where’s the chauffer?  And don’t those MotUs drive Mazerattis and Bentleys?  Is this guy trying to pull one over on the suburban rubes who buy Cadillacs stupidly thinking they’ve made it to the big time?)

Now the climax:  “You work hard, you create your own luck, and you gotta believe anything is possible,” he declaims.

Yes, we believe that!  The 17 million unemployed and underemployed, the 47 million who need food stamps to keep from starving, the 8 million families thrown out of their homes – WE ALL BELIEVE.  From all the windows in the neighborhood, from all the apartments across Harlem, from Sandy-shattered homes in Brooklyn and Staten Island, from the barren blast furnaces of Bethlehem and Youngstown, from the foreclosed neighborhoods in Detroit and Phoenix, from the 70-year olds doing Wal-mart inventory because their retirement went bust, from all the kitchens of all the families carrying $1 trillion in college debt, I hear the national chant, “YOU MAKE YOUR OWN LUCK!  YOU MAKE YOUR OWN LUCK!”

And finally – the denouement – from the front seat of his car, our Master of the Universe answers the question we’d all but forgotten.  “As for all the stuff? That’s the upside of taking only two weeks off in August.”  Then the final cold-blooded stare and – too true to be true – a manly wink, the kind of wink that makes us all collaborators and comrades-in-arms, and he inserts the final dagger: “N’est-ce pas?”

N’est-ce pas?

Categories: guest post

Guest Post: Beauty, even in the teaching of mathematics

This is a guest post by Manya Raman-Sundström.

Mathematical Beauty

If you talk to a mathematician about what she or he does, pretty soon it will surface that one reason for working those long hours on those difficult problems has to do with beauty.

Whatever we mean by that term, whether it is the way things hang together, or the sheer simplicity of a result found in a jungle of complexity, beauty – or aesthetics more generally—is often cited as one of the main rewards for the work, and in some cases the main motivating factor for doing this work. Indeed, the fact that a proof of known theorem can be published just because it is more elegant is one evidence of this fact.

Mathematics is beautiful. Any mathematician will tell you that. Then why is it that when we teach mathematics we tend not to bring out the beauty? We would consider it odd to teach music via scales and theory without ever giving children a chance to listen to a symphony. So why do we teach mathematics in bits and pieces without exposing students to the real thing, the full aesthetic experience?

Of course there are marvelous teachers out there who do manage to bring out the beauty and excitement and maybe even the depth of mathematics, but aesthetics is not something we tend to value at a curricular level. The new Common Core Standards that most US states have adopted as their curricular blueprint do not mention beauty as a goal. Neither do the curriculum guidelines of most countries, western or eastern (one exception is Korea).

Mathematics teaching is about achievement, not about aesthetic appreciation, a fact that test-makers are probably grateful for – can you imagine the makeover needed for the SAT if we started to try to measure aesthetic appreciation?

Why Does Beauty Matter?

First, it should be a bit troubling that our mathematics classrooms do not mirror practice. How can young people make wise decisions about whether they should continue to study mathematics if they have never really seen mathematics?

Second, to overlook the aesthetic components of mathematical thought might be to preventing our children from developing their intellectual capacities.

In the 1970s Seymour Papert , a well-known mathematician and educator, claimed that scientific thought consisted of three components: cognitive, affective, and aesthetic (for some discussion on aesthetics, see here).

At the time, research in education was almost entirely cognitive. In the last couple decades, the role of affect in thinking has become better understood, and now appears visibly in national curriculum documents. Enjoying mathematics, it turns out, is important for learning it. However, aesthetics is still largely overlooked.

Recently Nathalie Sinclair, of Simon Frasier University, has shown that children can develop aesthetic appreciation, even at a young age, somewhat analogously to mathematicians. But this kind of research is very far, currently, from making an impact on teaching on a broad scale.

Once one starts to take seriously the aesthetic nature of mathematics, one quickly meets some very tough (but quite interesting!) questions. What do we mean by beauty? How do we characterise it? Is beauty subjective, or objective (or neither? or both?) Is beauty something that can be taught, or does it just come to be experienced over time?

These questions, despite their allure, have not been fully explored. Several mathematicians (Hardy, Poincare, Rota) have speculated, but there is no definite answer even on the question of what characterizes beauty.

Example

To see why these questions might be of interest to anyone but hard-core philosophers, let’s look at an example. Consider the famous question, answered supposedly by Gauss, of the sum of the first n integers. Think about your favorite proof of this. Probably the proof that did NOT come to your mind first was a proof by induction:

Prove that S(n) = 1 + 2 + 3 … + n = n (n+1) /2

S(k + 1) = S(k) + (k + 1)

= k(k + 1)/2 + 2(k + 1)/2

= k(k + 1)/2 + 2(k + 1)/2

= (k + 1)(k + 2)/2.

Now compare this proof to another well known one. I will give the picture and leave the details to you:

Screen Shot 2014-02-04 at 6.53.05 AM

Does one of these strike you as nicer, or more explanatory, or perhaps even more beautiful than the other? My guess is that you will find the second one more appealing once you see that it is two sequences put together, giving an area of n (n+1), so S(n) = n (n+1)/2.

Note: another nice proof of this theorem, of course, is the one where S(n) is written both forwards and backwards and added. That proof also involves a visual component, as well as an algebraic one. See here for this and a few other proofs.

Beauty vs. Explanation

How often do we, as teachers, stop and think about the aesthetic merits of a proof? What is it, exactly, that makes the explanatory proof more attractive? In what way does the presentation of the proof make the key ideas accessible, and does this accessibility affect our sense of understanding, and what underpins the feeling that one has found exactly the right proof or exactly the right picture or exactly the right argument?

Beauty and explanation, while not obvious related (see here), might at least be bed-fellows. It may be the case that what lies at the bottom of explanation — a feeling of understanding, or a sense that one can ”see” what is going on — is also related to the aesthetic rewards we get when we find a particularly good solution.

Perhaps our minds are drawn to what is easiest to grasp, which brings us back to central questions of teaching and learning: how do we best present mathematics in a way that makes it understandable, clear, and perhaps even beautiful? These questions might all be related.

Workshop on Math Beauty

This March 10-12, 2014 in Umeå, Sweden, a group will gather to discuss this topic. Specifically, we will look at the question of whether mathematical beauty has anything to do with mathematical explanation. And if so, whether the two might have anything to do with visualization.

If this discussion peaks your interest at all, you are welcome to check out my blog on math beauty. There you will find a link to the workshop, with a fantastic lineup of philosophers, mathematicians, and mathematics educators who will come together to try to make some progress on these hard questions.

Thanks to Cathy, the always fabulous mathbabe, for letting me take up her space to share the news of this workshop (and perhaps get someone out there excited about this research area). Perhaps she, or you if you have read this far, would be willing to share your own favorite examples of beautiful mathematics. Some examples have already been collected here, please add yours.

Citigroup is the real reason we need the Volcker Rule

December 20, 2013 1 comment

This is a guest post by Tom Adams, who spent over 20 years in the securitization business and now works as an attorney and consultant and expert witness on MBS, CDO and securitization related issues. Jointly posted with Naked Capitalism.

Volcker Rule

Last week, the rules for the Volcker Rule – that provision of the Dodd-Frank Legislation that was intended to prevent (reduce?) proprietary trading by banks – were finalized.  As a consequence, there has been a lot of chatter among financial types around the internet about what the rule does and doesn’t do and how it is good or bad, etc.  Much of the conversation falls into the category of noise and distraction about unintended consequences, impacts on liquidity and broad views of regulatory effectiveness.

Citigroup

I call it noise, because in my view the real purpose of the Volcker Rule is to prevent another Citigroup bailout and therefore the measure of its effectiveness is whether the rule would accomplish this.

As you may recall, Citigroup required the largest bailout in government history in 2008, going back to the government well for more bailout funds several times.  The source of Citigroup’s pain was almost entirely due to its massive investment in the ABS CDO machine.  Of course, at the time of Citi’s bailout, there was a lot of noise about the potential financial system collapse and the risk posed by numerous other banks and institutions, so Citi as the main target of the TARP bailout, and ABS CDOs as the main cause of Citi’s pain, often gets lost in the folds of history.

The CDO market

In the years leading up to the financial crisis, Citi was an active underwriter for CDO’s backed by mortgage backed securities.  Selling these securities was a lucrative business for Citi and other banks – far more lucrative than the selling of the underlying MBS.  The hard part of selling was finding someone to take the highest risk piece (called the equity) of the CDO, but that problem got solved when Magnetar and other hedge funds came along with their ingenious shorting scheme.

The next hardest part was finding someone to take the risk of the very large senior class of the CDO, often known as the super-senior class (it was so named because it was enhanced at levels above that needed for a AAA rating).

For a time, Citi relied on a few overseas buyers and some insurance companies – like AIG and monoline bond insurers – to take on that risk.  In addition, the MBS market became heavily reliant upon CDOs to buy up the lower rated bonds from MBS securitizations.

As the frenzy of MBS selling escalated, though, the number of parties willing to take on the super-seniors was unable to match the volume of CDOs being created (AIG, for instance, pulled back from insuring the bonds in 2006).  Undeterred, Citi began to take down the super-senior bonds from the deals they were selling and holding them as “investments” which required very little capital because they were AAA.

This approach enabled Citi to continue the vey lucrative business of selling CDOs (to themselves!), which also enhanced their ability to create and sell MBS (to their CDOs), which enabled Citi to keep the music playing and the dance going, to paraphrase their then CEO Chuck Prince.

The CDO music stopped in July, 2007 with the rating agency downgrades of hundreds of the MBS bonds underlying the CDOs that had been created over the prior 24 months.  MBS and CDO issuance effectively shut down the following month and remained shut throughout the crisis.  The value of CDOs almost immediately began to plummet, leading to large mark-to-market losses for the parties that insured CDOs, such as Ambac and MBIA.

Citi managed to ignore the full extent of the declines in the value of the CDOs for nearly a year, until AIG ran into its troubles (itself a result of the mark-to-market declines in the values of its CDOs).  When, in the fall of 2008, Citi finally fessed up to the problems it was facing, it turned out it was holding super-senior CDOs with a face value of about $150 billion which were now worth substantially less.

How much less? The market opinion at the time was probably around 10-20 cents on the dollar.  Some of that value recovered in the last two years, but the bonds were considered fairly worthless for several years.  Citi’s difficulty in determining exactly how little the CDOs were worth and how many they held was the primary reason for the repeated requests for additional bailout money.

Citi’s bailout is everyone’s bailout

The Citi bailout was a huge embarrassment for the company and the regulators that oversaw the company (including the Federal Reserve) for failing to prevent such a massive aid package.  Some effort was made, at the time TARP money was distributed, to obscure Citi’s central role in the need for TARP and the panic the potential for a Citi failure was causing in the market and at the Treasury Department (see for example this story and the SIGTARP report).  By any decent measure, Citi should have been broken up after this fiasco, but at least some effort should be made from a large bank ever needing such a bailout again, right?

Volcker’s Rule is Citi’s rule

So the test for whether the Volcker Rule is effective is fairly simple: will it prevent Citi, or some other large institution, from getting in this situation again?  The rule is relatively complex and armies of lawyers are dissecting it for ways to arbitrage its words as we speak.

However, some evidence has emerged that the Volcker Rule would be effective in preventing another Citi fiasco.  While the bulk of the rules don’t become effective until 2015, banks are required to move all “covered assets” from held to maturity to held for sale, which requires them to move the assets to a fair market valuation from… whatever they were using before.

Just this week, for example, Zions Bank announced that they were taking a substantial impairment because of that rule and moving a big chunk of CDOs (trust preferred securities, or TRUPS, were the underlying asset, although the determination would apparently apply to all CDOs) to fair market accounting from… whatever valuation they were using previously (not fair market?).

Here’s the key point. Had Citi been forced to do this as they acquired their CDOs, there is a decent chance they would have run into CDO capacity problems much sooner – they may not have been able to rely on the AAA ratings, they might have had to sell off some of the bonds before the market imploded, and they might have had to justify their valuations with actual data rather than self-serving models.

As a secondary consequence, they probably would have had to stop buying and originating mortgage loans and buying and selling MBS, because they wouldn’t have been able to help create CDOs to dump them into.

Given the size of Citi’s CDO portfolio, and the leverage that those CDOs had as it relates to underlying mortgage loans (one $1 billion CDO was backed by MBS from about $10 billion mortgages, $150 billion of CDOs would have been backed by MBS from about $1.5 trillion of mortgage loans, theoretically), if Citi had slowed their buying of CDOs, it might have had a substantial cooling effect on the mortgage market before the crisis hit.

Categories: finance, guest post, news

Guest post: Rage against the algorithms

This is a guest post by , a Tow Fellow at the Columbia University Graduate School of Journalism where he is researching the use of data and algorithms in the news. You can find out more about his research and other projects on his website or by following him on Twitter. Crossposted from engenhonetwork with permission from the author.

shutterstock_125392883_650

How can we know the biases of a piece of software? By reverse engineering it, of course.

When was the last time you read an online review about a local business or service on a platform like Yelp? Of course you want to make sure the local plumber you hire is honest, or that even if the date is dud, at least the restaurant isn’t lousy. A recent survey found that 76 percent of consumers check online reviews before buying, so a lot can hinge on a good or bad review. Such sites have become so important to local businesses that it’s not uncommon for scheming owners to hire shills to boost themselves or put down their rivals.

To protect users from getting duped by fake reviews Yelp employs an algorithmic review reviewer which constantly scans reviews and relegates suspicious ones to a “filtered reviews” page, effectively de-emphasizing them without deleting them entirely. But of course that algorithm is not perfect, and it sometimes de-emphasizes legitimate reviews and leaves actual fakes intact—oops. Some businesses have complained, alleging that the filter can incorrectly remove all of their most positive reviews, leaving them with a lowly one- or two-stars average.

This is just one example of how algorithms are becoming ever more important in society, for everything from search engine personalizationdiscriminationdefamation, and censorship online, to how teachers are evaluated, how markets work, how political campaigns are run, and even how something like immigration is policed. Algorithms, driven by vast troves of data, are the new power brokers in society, both in the corporate world as well as in government.

They have biases like the rest of us. And they make mistakes. But they’re opaque, hiding their secrets behind layers of complexity. How can we deal with the power that algorithms may exert on us? How can we better understand where they might be wronging us?

Transparency is the vogue response to this problem right now. The big “open data” transparency-in-government push that started in 2009 was largely the result of an executive memo from President Obama. And of course corporations are on board too; Google publishes a biannual transparency report showing how often they remove or disclose information to governments. Transparency is an effective tool for inculcating public trust and is even the way journalists are now trained to deal with the hole where mighty Objectivity once stood.

But transparency knows some bounds. For example, though the Freedom of Information Act facilitates the public’s right to relevant government data, it has no legal teeth for compelling the government to disclose how that data was algorithmically generated or used in publicly relevant decisions (extensions worth considering).

Moreover, corporations have self-imposed limits on how transparent they want to be, since exposing too many details of their proprietary systems may undermine a competitive advantage (trade secrets), or leave the system open to gaming and manipulation. Furthermore, whereas transparency of data can be achieved simply by publishing a spreadsheet or database, transparency of an algorithm can be much more complex, resulting in additional labor costs both in creation as well as consumption of that information—a cognitive overload that keeps all but the most determined at bay. Methods for usable transparency need to be developed so that the relevant aspects of an algorithm can be presented in an understandable way.

Given the challenges to employing transparency as a check on algorithmic power, a new and complementary alternative is emerging. I call it algorithmic accountability reporting. At its core it’s really about reverse engineering—articulating the specifications of a system through a rigorous examination drawing on domain knowledge, observation, and deduction to unearth a model of how that system works.

As interest grows in understanding the broader impacts of algorithms, this kind of accountability reporting is already happening in some newsrooms, as well as in academic circles. At the Wall Street Journal a team of reporters probed e-commerce platforms to identify instances of potential price discrimination in dynamic and personalized online pricing. By polling different websites they were able to spot several, such as Staples.com, that were adjusting prices dynamically based on the location of the person visiting the site. At the Daily Beast, reporter Michael Keller dove into the iPhone spelling correction feature to help surface patterns of censorship and see which words, like “abortion,” the phone wouldn’t correct if they were misspelled. In my own investigation for Slate, I traced the contours of the editorial criteria embedded in search engine autocomplete algorithms. By collecting hundreds of autocompletions for queries relating to sex and violence I was able to ascertain which terms Google and Bing were blocking or censoring, uncovering mistakes in how these algorithms apply their editorial criteria.

All of these stories share a more or less common method. Algorithms are essentially black boxes, exposing an input and output without betraying any of their inner organs. You can’t see what’s going on inside directly, but if you vary the inputs in enough different ways and pay close attention to the outputs, you can start piecing together some likeness for how the algorithm transforms each input into an output. The black box starts to divulge some secrets.

Algorithmic accountability is also gaining traction in academia. At Harvard, Latanya Sweeney has looked at how online advertisements can be biased by the racial association of names used as queries. When you search for “black names” as opposed to “white names” ads using the word “arrest” appeared more often for online background check service Instant Checkmate. She thinks the disparity in the use of “arrest” suggests a discriminatory connection between race and crime. Her method, as with all of the other examples above, does point to a weakness though: Is the discrimination caused by Google, by Instant Checkmate, or simply by pre-existing societal biases? We don’t know, and correlation does not equal intention. As much as algorithmic accountability can help us diagnose the existence of a problem, we have to go deeper and do more journalistic-style reporting to understand the motivations or intentions behind an algorithm. We still need to answer the question of why.

And this is why it’s absolutely essential to have computational journalists not just engaging in the reverse engineering of algorithms, but also reporting and digging deeper into the motives and design intentions behind algorithms. Sure, it can be hard to convince companies running such algorithms to open up in detail about how their algorithms work, but interviews can still uncover details about larger goals and objectives built into an algorithm, better contextualizing a reverse-engineering analysis. Transparency is still important here too, as it adds to the information that can be used to characterize the technical system.

Despite the fact that forward thinkers like Larry Lessig have been writing for some time about how code is a lever on behavior, we’re still in the early days of developing methods for holding that code and its influence accountable. “There’s no conventional or obvious approach to it. It’s a lot of testing or trial and error, and it’s hard to teach in any uniform way,” noted Jeremy Singer-Vine, a reporter and programmer who worked on the WSJ price discrimination story. It will always be a messy business with lots of room for creativity, but given the growing power that algorithms wield in society it’s vital to continue to develop, codify, and teach more formalized methods of algorithmic accountability. In the absence of new legal measures, it may just provide a novel way to shed light on such systems, particularly in cases where transparency doesn’t or can’t offer much clarity.

Don’t Fly During Ramadan

Crossposted from /var/null, a blog written by Aditya Mukerjee. Aditya graduated from Columbia with a degree in CS and statistics, was a hackNY Fellow, worked in data at OkCupid, and on the server team at foursquare. He currently serves as the Hacker-in-Residence at Quotidian Ventures

A couple of weeks ago, I was scheduled to take a trip from New York (JFK) to Los Angeles on JetBlue. Every year, my family goes on a one-week pilgrimage, where we put our work on hold and spend time visiting temples, praying, and spending time with family and friends. To my Jewish friends, I often explain this trip as vaguely similar to the Sabbath, except we take one week of rest per year, rather than one day per week.

Our family is not Muslim, but by coincidence, this year, our trip happened to be during the last week of Ramadan.

By further coincidence, this was also the same week that I was moving out of my employer-provided temporary housing (at NYU) and moving into my new apartment. The night before my trip, I enlisted the help of two friends and we took most of my belongings, in a couple of suitcases, to my new apartment. The apartment was almost completely unfurnished – I planned on getting new furniture upon my return – so I dropped my few bags (one containing an air mattress) in the corner. Even though I hadn’t decorated the apartment yet, in accordance with Hindu custom, I taped a single photograph to the wall in my bedroom — a long-haired saint with his hands outstretched in pronam (a sign of reverence and respect).

The next morning, I packed the rest of my clothes into a suitcase and took a cab to the airport. I didn’t bother to eat breakfast, figuring I would grab some yogurt in the terminal while waiting to board.

I got in line for security at the airport and handed the agent my ID. Another agent came over and handed me a paper slip, which he said was being used to track the length of the security lines. He said, “just hand this to someone when your stuff goes through the x-ray machines, and we’ll know how long you were in line.’ I looked at the timestamp on the paper: 10:40.

When going through the security line, I opted out (as I always used to) of the millimeter wave detectors. I fly often enough, and have opted out often enough, that I was prepared for what comes next: a firm pat-down by a TSA employee wearing non-latex gloves, who uses the back of his hand when patting down the inside of the thighs.

After the pat-down, the TSA agent swabbed his hands with some cotton-like material and put the swab in the machine that supposedly checks for explosive residue. The machine beeped. “We’re going to need to pat you down again, this time in private,” the agent said.

Having been selected before for so-called “random” checks, I assumed that this was another such check.

“What do you mean, ‘in private’? Can’t we just do this out here?”

“No, this is a different kind of pat-down, and we can’t do that in public.” When I asked him why this pat-down was different, he wouldn’t tell me. When I asked him specifically why he couldn’t do it in public, he said “Because it would be obscene.”

Naturally, I balked at the thought of going somewhere behind closed doors where a person I just met was going to touch me in “obscene” ways. I didn’t know at the time (and the agent never bothered to tell me) that the TSA has a policy that requires two agents to be present during every private pat-down. I’m not sure if that would make me feel more or less comfortable.

Noticing my hesitation, the agent offered to have his supervisor explain the procedure in more detail. He brought over his supervisor, a rather harried man who, instead of explaining the pat-down to me, rather rudely explained to me that I could either submit immediately to a pat-down behind closed-doors, or he could call the police.

At this point, I didn’t mind having to leave the secure area and go back through security again (this time not opting out of the machines), but I didn’t particularly want to get the cops involved. I told him, “Okay, fine, I’ll leave”.

“You can’t leave here.”

“Are you detaining me, then?” I’ve been through enough “know your rights” training to know how to handle police searches; however, TSA agents are not law enforcement officials. Technically, they don’t even have the right to detain you against your will.

“We’re not detaining you. You just can’t leave.” My jaw dropped.

“Either you’re detaining me, or I’m free to go. Which one is it?” I asked.

He glanced for a moment at my backpack, then snatched it out of the conveyor belt. “Okay,” he said. “You can leave, but I’m keeping your bag.”

I was speechless. My bag had both my work computer and my personal computer in it. The only way for me to get it back from him would be to snatch it back, at which point he could simply claim that I had assaulted him. I was trapped.

While we waited for the police to arrive, I took my phone and quickly tried to call my parents to let them know what was happening. Unfortunately, my mom’s voicemail was full, and my dad had never even set his up.

“Hey, what’s he doing?” One of the TSA agents had noticed I was touching my phone. “It’s probably fine; he’s leaving anyway,” another said.

The cops arrived a few minutes later, spoke with the TSA agents for a moment, and then came over and gave me one last chance to submit to the private examination. “Otherwise, we have to escort you out of the building.” I asked him if he could be present while the TSA agent was patting me down.

“No,” he explained, “because when we pat people down, it’s to lock them up.”

I only realized the significance of that explanation later. At this point, I didn’t particularly want to miss my flight. Foolishly, I said, “Fine, I’ll do it.”

The TSA agents and police escorted me to a holding room, where they patted me down again – this time using the front of their hands as they passed down the front of my pants. While they patted me down, they asked me some basic questions.

“What’s the purpose of your travel?”

“Personal,” I responded, (as opposed to business).

“Are you traveling with anybody?”

“My parents are on their way to LA right now; I’m meeting them there.”

“How long is your trip?”

“Ten days.”

“What will you be doing?”

Mentally, I sighed. There wasn’t any other way I could answer this next question.

“We’ll be visiting some temples.” He raised his eyebrow, and I explained that the next week was a religious holiday, and that I was traveling to LA to observe it with my family.

After patting me down, they swabbed not only their hands, but also my backpack, shoes, wallet, and belongings, and then walked out of the room to put it through the machine again. After more than five minutes, I started to wonder why they hadn’t said anything, so I asked the police officer who was guarding the door. He called over the TSA agent, who told me,

“You’re still setting off the alarm. We need to call the explosives specialist”.

I waited for about ten minutes before the specialist showed up. He walked in without a word, grabbed the bins with my possessions, and started to leave. Unlike the other agents I’d seen, he wasn’t wearing a uniform, so I was a bit taken aback.

“What’s happening?” I asked.

“I’m running it through the x-ray again,” he snapped. “Because I can. And I’m going to do it again, and again, until I decide I’m done”. He then asked the TSA agents whether they had patted me down. They said they had, and he just said, “Well, try again”, and left the room. Again I was told to stand with my legs apart and my hands extended horizontally while they patted me down all over before stepping outside.

The explosives specialist walked back into the room and asked me why my clothes were testing positive for explosives. I told him, quite truthfully, “I don’t know.” He asked me what I had done earlier in the day.

“Well, I had to pack my suitcase, and also clean my apartment.”

“And yesterday?”

“I moved my stuff from my old apartment to my new one”.

“What did you eat this morning?”

“Nothing,” I said. Only later did I realize that this made it sound like I was fasting, when in reality, I just hadn’t had breakfast yet.

“Are you taking any medications?”

The other TSA agents stood and listened while the explosives specialist and asked every medication I had taken “recently”, both prescription and over-the-counter, and asked me to explain any medical conditions for which any prescription medicine had been prescribed. Even though I wasn’t carrying any medication on me, he still asked for my complete “recent” medical history.

“What have you touched that would cause you to test positive for certain explosives?”

“I can’t think of anything. What does it say is triggering the alarm?” I asked.

“I’m not going to tell you! It’s right here on my sheet, but I don’t have to tell you what it is!” he exclaimed, pointing at his clipboard.

I was at a loss for words. The first thing that came to my mind was, “Well, I haven’t touched any explosives, but if I don’t even know what chemical we’re talking about, I don’t know how to figure out why the tests are picking it up.”

He didn’t like this answer, so he told them to run my belongings through the x-ray machine and pat me down again, then left the room.

I glanced at my watch. Boarding would start in fifteen minutes, and I hadn’t even had anything to eat. A TSA officer in the room noticed me craning my neck to look at my watch on the table, and he said, “Don’t worry, they’ll hold the flight.”

As they patted me down for the fourth time, a female TSA agent asked me for my baggage claim ticket. I handed it to her, and she told me that a woman from JetBlue corporate security needed to ask me some questions as well. I was a bit surprised, but agreed. After the pat-down, the JetBlue representative walked in and cooly introduced herself by name.

She explained, “We have some questions for you to determine whether or not you’re permitted to fly today. Have you flown on JetBlue before?”

“Yes”

“How often?”

“Maybe about ten times,” I guessed.

“Ten what? Per month?”

“No, ten times total.”

She paused, then asked,

“Will you have any trouble following the instructions of the crew and flight attendants on board the flight?”

“No.” I had no idea why this would even be in doubt.

“We have some female flight attendants. Would you be able to follow their instructions?”

I was almost insulted by the question, but I answered calmly, “Yes, I can do that.”

“Okay,” she continued, “and will you need any special treatment during your flight? Do you need a special place to pray on board the aircraft?”

Only here did it hit me.

“No,” I said with a light-hearted chuckle, trying to conceal any sign of how offensive her questions were. “Thank you for asking, but I don’t need any special treatment.”

She left the room, again, leaving me alone for another ten minutes or so. When she finally returned, she told me that I had passed the TSA’s inspection. “However, based on the responses you’ve given to questions, we’re not going to permit you to fly today.”

I was shocked. “What do you mean?” were the only words I could get out.

“If you’d like, we’ll rebook you for the flight tomorrow, but you can’t take the flight this afternoon, and we’re not permitting you to rebook for any flight today.”

I barely noticed the irony of the situation – that the TSA and NYPD were clearing me for takeoff, but JetBlue had decided to ground me. At this point, I could think of nothing else but how to inform my family, who were expecting me to be on the other side of the country, that I wouldn’t be meeting them for dinner after all. In the meantime, an officer entered the room and told me to continue waiting there. “We just have one more person who needs to speak with you before you go.” By then, I had already been “cleared” by the TSA and NYPD, so I couldn’t figure out why I still needed to be questioned. I asked them if I could use my phone and call my family.

“No, this will just take a couple of minutes and you’ll be on your way.” The time was 12.35.

He stepped out of the room – for the first time since I had been brought into the cell, there was no NYPD officer guarding the door. Recognizing my short window of opportunity, I grabbed my phone from the table and quickly texted three of my local friends – two who live in Brooklyn, and one who lives in Nassau County – telling them that I had been detained by the TSA and that I couldn’t board my flight. I wasn’t sure what was going to happen next, but since nobody had any intention of reading me my Miranda rights, I wanted to make sure people knew where I was.

After fifteen minutes, one of the police officers marched into the room and scolded, “You didn’t tell us you have a checked bag!” I explained that I had already handed my baggage claim ticket to a TSA agent, so I had in fact informed someone that I had a checked bag. Looking frustrated, he turned and walked out of the room, without saying anything more.

After about twenty minutes, another man walked in and introduced himself as representing the FBI. He asked me many of the same questions I had already answered multiple times – my name, my address, what I had done so far that day. etc.

He then asked, “What is your religion?”

“I’m Hindu.”

“How religious are you? Would you describe yourself as ‘somewhat religious’ or ‘very religious’?”

I was speechless from the idea of being forced to talk about my the extent of religious beliefs to a complete stranger. “Somewhat religious”, I responded.

“How many times a day do you pray?” he asked. This time, my surprise must have registered on my face, because he quickly added, “I’m not trying to offend you; I just don’t know anything about Hinduism. For example, I know that people are fasting for Ramadan right now, but I don’t have any idea what Hindus actually do on a daily basis.”

I nearly laughed at the idea of being questioned by a man who was able to admit his own ignorance on the subject matter, but I knew enough to restrain myself. The questioning continued for another few minutes. At one point, he asked me what cleaning supplies I had used that morning.

“Well, some window cleaner, disinfectant -” I started, before he cut me off.

“This is important,” he said, sternly. “Be specific.” I listed the specific brands that I had used.

Suddenly I remembered something: the very last thing I had done before leaving was to take the bed sheets off of my bed, as I was moving out. Since this was a dorm room, to guard against bedbugs, my dad (a physician) had given me an over-the-counter spray to spray on the mattress when I moved in, over two months previously. Was it possible that that was still active and triggering their machines?

“I also have a bedbug spray,” I said. “I don’t know the name of it, but I knew it was over-the-counter, so I figured it probably contained permethrin.” Permethrin is an insecticide, sold over-the-counter to kill bed bugs and lice.

“Perm-what?” He asked me to spell it.

After he wrote it down, I asked him if I could have something to drink. “I’ve been here talking for three hours at this point,” I explained. “My mouth is like sandpaper”. He refused, saying

“We’ll just be a few minutes, and then you’ll be able to go.”

“Do you have any identification?” I showed him my drivers license, which still listed my old address. “You have nothing that shows your new address?” he exclaimed.

“Well, no, I only moved there on Thursday.”

“What about the address before that?”

“I was only there for two months – it was temporary housing for work”. I pulled my NYU ID out of my wallet. He looked at it, then a police officer in the room took it from him and walked out.

“What about any business cards that show your work address?” I mentally replayed my steps from the morning, and remembered that I had left behind my business card holder, thinking I wouldn’t need it on my trip.

“No, I left those at home.”

“You have none?”

“Well, no, I’m going on vacation, so I didn’t refill them last night.” He scoffed. “I always carry my cards on me, even when I’m on vacation.” I had no response to that – what could I say?

“What about a direct line at work? Is there a phone number I can call where it’ll patch me straight through to your voicemail?”

“No,” I tried in vain to explain. “We’re a tech company; everyone just uses their cell phones”. To this day, I don’t think my company has a working landline phone in the entire office – our “main line” is a virtual assistant that just forwards calls to our cell phones. I offered to give him the name and phone number of one of our venture partners instead, which he reluctantly accepted.

Around this point, the officer who had taken my NYU ID stormed into the room.

“They put an expiration sticker on your ID, right?” I nodded. “Well then why did this ID expire in 2010?!” he accused.

I took a look at the ID and calmly pointed out that it said “August 2013” in big letters on the ID, and that the numbers “8/10” meant “August 10th, 2013”, not “August, 2010”. I added, “See, even the expiration sticker says 2013 on it above the date”. He studied the ID again for a moment, then walked out of the room again, looking a little embarrassed.

The FBI agent resumed speaking with me. “Do you have any credit cards with your name on them?” I was hesitant to hand them a credit card, but I didn’t have much of a choice. Reluctantly, I pulled out a credit card and handed it to him. “What’s the limit on it?” he said, and then, noticing that I didn’t laugh, quickly added, “That was a joke.”

He left the room, and then a series of other NYPD and TSA agents came in and started questioning me, one after the other, with the same questions that I’d already answered previously. In between, I was left alone, except for the officer guarding the door.

At one point, when I went to the door and asked the officer when I could finally get something to drink, he told me, “Just a couple more minutes. You’ll be out of here soon.”

“That’s what they said an hour ago,” I complained.

“You also said a lot of things, kid,” he said with a wink. “Now sit back down”.

I sat back down and waited some more. Another time, I looked up and noticed that a different officer was guarding the door. By this time, I hadn’t had any food or water in almost eighteen hours. I could feel the energy draining from me, both physically and mentally, and my head was starting to spin. I went to the door and explained the situation the officer. “At the very least, I really need something to drink.”

“Is this a medical emergency? Are you going to pass out? Do we need to call an ambulance?” he asked, skeptically. His tone was almost mocking, conveying more scorn than actual concern or interest.

“No,” I responded. I’m not sure why I said that. I was lightheaded enough that I certainly felt like I was going to pass out.

“Are you diabetic?”

“No,” I responded.

Again he repeated the familiar refrain. “We’ll get you out of here in a few minutes.” I sat back down. I was starting to feel cold, even though I was sweating – the same way I often feel when a fever is coming on. But when I put my hand to my forehead, I felt fine.

One of the police officers who questioned me about my job was less-than-familiar with the technology field.

“What type of work do you do?”

“I work in venture capital.”

“Venture Capital – is that the thing I see ads for on TV all the time?” For a moment, I was dumbfounded – what venture capital firm advertises on TV? Suddenly, it hit me.

“Oh! You’re probably thinking of Capital One Venture credit cards.” I said this politely and with a straight face, but unfortunately, the other cop standing in the room burst out laughing immediately. Silently, I was shocked – somehow, this was the interrogation procedure for confirming that I actually had the job I claimed to have.

Another pair of NYPD officers walked in, and one asked me to identify some landmarks around my new apartment. One was, “When you’re facing the apartment, is the parking on the left or on the right?” I thought this was an odd question, but I answered it correctly. He whispered something in the ear of the other officer, and they both walked out.

The onslaught of NYPD agents was broken when a South Asian man with a Homeland Security badge walked in and said something that sounded unintelligible. After a second, I realized he was speaking Hindi.

“Sorry, I don’t speak Hindi.”

“Oh!” he said, noticeably surprised at how “Americanized” this suspect was. We chatted for a few moments, during which time I learned that his family was Pakistani, and that he was Muslim, though he was not fasting for Ramadan. He asked me the standard repertoire of questions that I had been answering for other agents all day.

Finally, the FBI agent returned.

“How are you feeling right now?” he asked. I wasn’t sure if he was expressing genuine concern or interrogating me further, but by this point, I had very little energy left.

“A bit nauseous, and very thirsty.”

“You’ll have to understand, when a person of your… background walks into here, travelling alone, and sets off our alarms, people start to get a bit nervous. I’m sure you’ve been following what’s been going on in the news recently. You’ve got people from five different branches of government all in here – we don’t do this just for fun.”

He asked me to repeat some answers to questions that he’d asked me previously, looking down at his notes the whole time, then he left. Finally, two TSA agents entered the room and told me that my checked bag was outside, and that I would be escorted out to the ticketing desks, where I could see if JetBlue would refund my flight.

It was 2:20PM by the time I was finally released from custody. My entire body was shaking uncontrollably, as if I were extremely cold, even though I wasn’t. I couldn’t identify the emotion I was feeling. Surprisingly, as far as I could tell, I was shaking out of neither fear nor anger – I felt neither of those emotions at the time. The shaking motion was entirely involuntary, and I couldn’t force my limbs to be still, no matter how hard I concentrated.

In the end, JetBlue did refund my flight, but they cancelled my entire round-trip ticket. Because I had to rebook on another airline that same day, it ended up costing me about $700 more for the entire trip. Ironically, when I went to the other terminal, I was able to get through security (by walking through the millimeter wave machines) with no problem.

I spent the week in LA, where I was able to tell my family and friends about the entire ordeal. They were appalled by the treatment I had received, but happy to see me safely with them, even if several hours later.

I wish I could say that the story ended there. It almost did. I had no trouble flying back to NYC on a red-eye the next week, in the wee hours of August 12th. But when I returned home the next week, opened the door to my new apartment, and looked around the room, I couldn’t help but notice that one of the suitcases sat several inches away from the wall. I could have sworn I pushed everything to the side of the room when I left, but I told myself that I may have just forgotten, since I was in a hurry when I dropped my bags off.

When I entered my bedroom, a chill went down my spine: the photograph on my wall had vanished. I looked around the room, but in vain. My apartment was almost completely empty; there was no wardrobe it could have slipped under, even on the off-chance it had fallen.

To this day, that photograph has not turned up. I can’t think of any “rational” explanation for it. Maybe there is one. Maybe a burglar broke into my apartment by picking the front door lock and, finding nothing of monetary value, took only my picture. In order to preserve my peace-of-mind, I’ve tried to convince myself that that’s what happened, so I can sleep comfortably at night.

But no matter how I’ve tried to rationalize this in the last week and a half, nothing can block out the memory of the chilling sensation I felt that first morning, lying on my air mattress, trying to forget the image of large, uniformed men invading the sanctuary of my home in my absence, wondering when they had done it, wondering why they had done it.

In all my life, I have only felt that same chilling terror once before – on one cold night in September twelve years ago, when I huddled in bed and tried to forget the terrible events in the news that day, wondering why they they had happened, wondering whether everything would be okay ever again.

Update: this has been picked up by Village Voice and Gawker and JetBlue has apologized over twitter.

Categories: guest post

How much is the Stacks Project graph like a random graph?

This is a guest post from Jordan Ellenberg, a professor of mathematics at the University of Wisconsin. Jordan’s book, How Not To Be Wrong, comes out in May 2014. It is crossposted from his blog, Quomodocumque, and tweeted about at @JSEllenberg.

Cathy posted some cool data yesterday coming from the new visualization features of the magnificent Stacks Project. Summary: you can make a directed graph whose vertices are the 10,445 tagged assertions in the Stacks Project, and whose edges are logical dependency. So this graph (hopefully!) doesn’t have any directed cycles. (Actually, Cathy tells me that the Stacks Project autovomits out any contribution that would create a logical cycle! I wish LaTeX could do that.)

Given any assertion v, you can construct the subgraph G_v of vertices which are the terminus of a directed path starting at v. And Cathy finds that if you plot the number of vertices and number of edges of each of these graphs, you get something that looks really, really close to a line.

Why is this so? Does it suggest some underlying structure? I tend to say no, or at least not much — my guess is that in some sense it is “expected” for graphs like this to have this sort of property.

Because I am trying to get strong at sage I coded some of this up this morning. One way to make a random directed graph with no cycles is as follows: start with N edges, and a function f on natural numbers k that decays with k, and then connect vertex N to vertex N-k (if there is such a vertex) with probability f(k). The decaying function f is supposed to mimic the fact that an assertion is presumably more likely to refer to something just before it than something “far away” (though of course the stack project is not a strictly linear thing like a book.)

Here’s how Cathy’s plot looks for a graph generated by N= 1000 and f(k) = (2/3)^k, which makes the mean out-degree 2 as suggested in Cathy’s post.

stacksgraph_expmean2

Pretty linear — though if you look closely you can see that there are really (at least) a couple of close-to-linear “strands” superimposed! At first I thought this was because I forgot to clear the plot before running the program, but no, this is the kind of thing that happens.

Is this because the distribution decays so fast, so that there are very few long-range edges? Here’s how the plot looks with f(k) = 1/k^2, a nice fat tail yielding many more long edges:

stacksgraph_inversesquare

My guess: a random graph aficionado could prove that the plot stays very close to a line with high probability under a broad range of random graph models. But I don’t really know!

Update: Although you know what must be happening here? It’s not hard to check that in the models I’ve presented here, there’s a huge amount of overlap between the descendant graphs; in fact, a vertex is very likely to be connected all but c of the vertices below it for a suitable constant c.

I would guess the Stacks Project graph doesn’t have this property (though it would be interesting to hear from Cathy to what extent this is the case) and that in her scatterplot we are not measuring the same graph again and again.

It might be fun to consider a model where vertices are pairs of natural numbers and (m,n) is connected to (m-k,n-l) with probability f(k,l) for some suitable decay. Under those circumstances, you’d have substantially less overlap between the descendant trees; do you still get the approximately linear relationship between edges and nodes?

Categories: guest post, math, statistics

Huma’s Little Weiner Problem

This is a guest post by my friend Laura Strausfeld.

As an unlicensed psychotherapist, here’s my take on why Huma Abedin is supporting her husband Anthony Weiner’s campaign for mayor:

It’s all about the kid.

Jordan Weiner is 19 months old. When he’s 8 or 9—or 5, and wearing google glasses—maybe he’ll google his name and read about his father’s penis. Either that, or one of his buddies at school may ask him about his father’s penis. Jordan might then ask his mommy and daddy about his father’s penis and they’ll tell him either 1) your daddy was a great politician, but had to resign from Congress because he admitted to showing people his penis, which we recommend you don’t do, especially when you’re a grownup and on twitter; or 2) your daddy was a great politician and ran a very close race for mayor—that’s right, your daddy was almost mayor of New York City!—but he lost because people said he showed people his penis and that’s none of anybody’s business.

Let’s look at this from Huma’s perspective. She’s got a child for a husband, with a weird sexual addiction that on the positive side, doesn’t appear to carry the threat of STDs. But her dilemma is not about her marriage. The marriage is over. What she cares about is Jordan. And this is where she’s really fucked. Whatever happens, Anthony will always be her child’s father.

That bears repeating. You’ve got a child you love more than anything in the world, will sacrifice anything for, and will always now be stigmatized as the son of a celebrity-sized asshole. What are your choices?

The best scenario for Huma is if Anthony becomes mayor. Then she can divorce his ass, get primary custody and protect her child from growing up listening to penis jokes about his loser father. There will be jokes, but at least they’ll be about the mayor’s penis. And with a whole lot of luck, they might even be about how his father’s penis was a lot smaller in the mind of the public than his policies.

Weiner won’t get my vote, however. And for that, I apologize to you, Jordan. You have my sympathy, Huma.

Categories: guest post
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