The kind of abstract cognitive pursuits that occupy us in the modern industrialized world are comparatively recent developments. For the vast majority of human history, life has been about simple survival. Both our minds and our bodies are adapted to that task – to make sure that we don't freeze or starve to death, to avoid things trying to kill us, and to make choices that promote our self-interest. That you are here today as the culmination of a million years of human evolution is a good indication that your brain is hard wired for survival.

In a complex world in which many of us are lucky enough to avoid worrying about survival on a daily basis, we have adapted our cognitive abilities to contemplate more abstract concepts. We're capable of understanding things like philosophy, religion, politics, and relationships. But old habits die hard, so to speak. Our minds retain a nagging tendency to distort or manipulate information in ways that enhance our well being, which is a fancy way of saying your brain wants you to feel better about yourself.

Now. Consider this:

I won't dissect this person's statement, which is almost certainly either selective with the truth or exaggerated. That's another story (and ably handled in detail here). What we see is a very common perceptual bias in action: the "just world" phenomenon, a bias of attribution.
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If I am a success, my brain wants me to believe that I have succeeded because I am good – talented, hard working, and so on. The converse is that people who do not succeed must be lazy, talentless, or prone to making bad decisions. It's a basic victim-blaming premise. A common example used with this bias is rape. If we blame the victim, it makes us feel safer. Rather than confronting the scary reality that it could happen to you at random, we believe that if we avoid the behaviors of the previous victims then we will remain safe.

Thus the overly simplistic worldview we see on display in the above photo. We start with our brain's desire to bolster our self-image – You're a big success, Timmy! You've earned all that you have! – and end with a worldview that requires us to assign the same level of responsibility to others. If we admit that external factors such as chance or social class influence others' outcomes, then we would be admitting that the same things might have benefited us. But of course I didn't just "get lucky"…I earned all of this. So don't you whiners go blaming bad luck or forces beyond your control if you're not happy. You've clearly made a lot of bad decisions, the same kind that I'm smart enough to avoid.

It all makes sense now.


We don't know what we think about a lot of issues – hardly a novel finding, dating back to Converse. What's even more problematic is how badly we misjudge what others think, which is a fundamental component of how we form our own opinions and orient ourselves toward society.

A real psychologist might disagree here, but political psychology evaluates judgment and decision-making under the assumption that much of human cognition is "hard wired" for basic survival functions and is quite poorly adapted to understanding abstractions like politics (see Kuklinski & Quirk, Reconsidering the Rational Public: Cognition, Heuristics, and Mass Opinion). In other words, our thought processes are geared toward self-preservation, including bolstering our self-image. This is part of the reason why having a low self-image is recognized as a medical condition. The "normal" mind excels at convincing itself that it is correct even when it is very, very wrong.

One of the tricks our minds use to make us feel better about the decisions we make is to convince us that others share our opinions. It is common in the absence of other information (and perhaps even despite it) to believe that the majority of our fellow citizens believe the same things we do. If I am against capital punishment and don't know anything about public opinion on that subject, I will guess that a majority of the public is also against it.

This, I believe, is one of the main culprits explaining survey results like these:

Virginia Commonwealth University Life Sciences Survey. May 12-18, 2010. N=1,001 adults nationwide. MoE ± 3.7
"From what you’ve heard or read, do you think the evidence on global warming is widely accepted within the scientific community, or do many scientists have serious doubts about it?"

  • Widely accepted: 37%
  • Many have serious doubts: 49%
  • Unsure: 14%
  • ABC News/Washington Post Poll. Dec. 10-13, 2009. N=1,003 adults nationwide. MoE ± 3.5
    "Do you think most scientists agree with one another about whether or not global warming is happening, or do you think there is a lot of disagreement among scientists on this issue?"

  • Most agree: 36%
  • A lot of disagreement: 62%
  • Unsure: 2%
  • Your gut reaction is probably that this is the media's fault – too much Glenn Beck, too many effective disinformation campaigns by denialist groups and professional "skeptics." But these are objective questions, namely about the scientific consensus. A five-second google search would reveal that 90%+ of climate researchers subscribe to the climate change hypothesis. Even denialist arguments on Fox News don't have the audacity to claim that a majority of scientists have serious doubts; in fact, the small minority status of the Skeptics is often played up to fuel the right's latent martyr complex. If we had the information we would probably answer the question accordingly. Lacking that information we just assume that everybody else probably believes what we believe, namely that global warmin' is nothing but a big pinko conspiracy to take away our Dodge Durango.

    It is regrettable that we use our own opinions as a proxy for the majority so often given how sorely misinformed we are most of the time. But if I feel that it's regrettable, then surely most people do. A collective solution may be just around the corner.


    I come across like someone who is very harsh on students but more often than not I just feel bad for them when they're at their worst. Most of what they are at 18-21 reflects their upbringing, and I'm not eager to punish them for the fact that they grew up in Pigsknuckle, Tennessee or were raised by people whose parenting skills were limited to showering them with money and looking the other way. I mean, given that they were raised on Glenn Beck, drive a car that costs twice my annual salary, and have never met a black person who wasn't serving them food or holding a rake, the only surprise is that they're not more screwed up than they already are. The existential dilemma of teaching becomes clear when you try telling some lackadaisical fratboy "You need to try harder" when it's clear that he already has everything and very clearly doesn't need to try in order to maintain it. But I digress.

    The point is that I understand that the decision-making skills of undergrads are subpar. That is not an excuse; they are old enough to accept consequences. I simply mean that it does not shock me when students – especially groups of them – make idiotic decisions. It is what they do. I expect it. This is what I tell myself. But every so often I reel from shock despite how well I prepare myself for their ignorance.

    University of California-San Diego is the latest school to have what amounts to an annual tradition in American academia: the comically racist frat party. This year's UCSD "Compton Cookout" is just the latest version of the fraternity slave auctions, the blackface and gold teeth Halloween costumes, and the fried chicken-and-watermelon email "jokes" that we've come to know and love. The invitation to this year's event promises attendees "dat purple drank" – which is what the coloreds drink! ha ha! – and helpfully offers the following tips:

    For girls: For those of you who are unfamiliar with ghetto chicks-Ghetto chicks usually have gold teeth, start fights and drama, and wear cheap clothes – they consider Baby Phat to be high class and expensive couture. They also have short, nappy hair, and usually wear cheap weave, usually in bad colors, such as purple or bright red.

    They look and act similar to Shenaynay, and speak very loudly, while rolling their neck, and waving their finger in your face. Ghetto chicks have a very limited vocabulary, and attempt to make up for it, by forming new words, such as "constipulated", or simply cursing persistently, or using other types of vulgarities, and making noises, such as "hmmg!", or smacking their lips, and making other angry noises, grunts, and faces.

    The objective is for all you lovely ladies to look, act, and essentially take on these "respectable" qualities throughout the day.

    Hilarity ensues.

    Here's what baffles me about these incidents. I know these kids are mostly the ignorant progeny of ignorant adults, but fraternities are large. The planning of this party had to involve dozens and dozens of people (within and outside of the frat in question). There wasn't one person with enough brainpower to think, "Hmm, this doesn't seem like a good idea"? Not one? I understand groupthink, peer pressure, and conformity. Honestly I do. Cognitive biases interest me. But you would imagine that if for no reason other than self-preservation – "Gee, I don't want to get in trouble for this" – one out of every hundred would be smart enough to do something. Even my jaded, blackened heart has a hard time believing that they are unanimously that dumb.

    Overall today's undergrads are probably less racist than past generations so we can't make a good-ol'-days argument here. But the sheer stupidity of the racism that remains more than compensates for whatever improvements we've made as a society. It's sad enough that this happens, and sadder yet that these people are too dumb to express their racism at a level higher than "Haw haw! Them negroes sure do talk real funny and drink lotsa Kool Aid!" If the sentiments they express aren't enough to convince us of their dull minds, they ensure that we get the message with their chosen manner of delivery. I mean, if you're going to be completely offensive you could at least do humanity the favor of attempting to be clever. Then again, if these people were mentally capable of clever they'd wouldn't be doing this in the first place.


    Optimism is an inherently good thing, right?

    Be honest with yourself for a moment. How many times have you compensated, consciously or otherwise, for a lousy plan with the phrases "I'll figure something out" or "It'll all work out"? Statistically, you won't and it won't. But our minds are great at convincing us that these phrases are not merely a rapid escape hatch from a conversation we don't want to have; we're hard-wired to believe it.

    Optimism bias is one of the oldest and most well-established facts in psychology and cognitive science. Armor & Taylor (2002) run down a list of experimental evidence. But if this seems like a simple phenomenon, it isn't. The problem is not that we underestimate the odds of negative outcomes even when we have full information (contrarily, in fact, we tend to wildly overestimate the odds of unlikely negative consequences – plane crashes, being hit by lightning, satanic ritual abuse, etc.). An example of that kind of reasoning might be, "I know 90% of smokers develop lung cancer, but I'll be one of the 10%." There's no need to give that a fancy name; denial and stupidity work just fine. No, optimism bias is our ability to convince ourselves that we're not in denial of the odds – instead, we tell ourselves we've found a way to change them in our favor.

    We know that 75% of credit card holders make a late payment at some point, allowing issuers to impose punitive fees and APRs, but you won't be one of those people because you're very organized and you always pay on time.

    Students beginning law or business school (and sinking $100k in the process) wildly overestimate their odds of getting one of the high-paying jobs one gets by finishing in the top 10. It's obvious that only 10% of any class can have that outcome, but the odds are not 9 to 1 against me because I'll study harder than everyone else and I'm smarter anyway.

    Smokers routinely convince themselves that the grim statistics about tobacco and mortality are attenuated by some other behavior, i.e. your odds of getting lung cancer aren't really 80% because you smoke but you also jog three times per week and eat lots of organic stuff (or even more hilariously, "because I smoke lights / brand X / etc.")

    Confronted with the cold reality that 50% of marriages fail, newlyweds inevitably conclude that their special bond with one another makes their odds of avoiding divorce much better than 50-50.

    Gamblers understand that the odds are always on the house, but you have some kind of "system" – counting cards or whatever – that means the odds don't apply to you.

    I can't help but think about optimism bias when I look at the daunting statistics about foreclosures and delinquent mortgages. Lazy minds assume that the problem is as simple as poor people taking out loans they couldn't afford, but when we look at the geographic distribution we see the fastest-growing states are leading the way – Nevada, Arizona, California, and Florida. In other words, the places where the upper-middle class buys its vacation properties and eventually moves to retire. Behind every bad loan, "investment property," and second mortgage is a series of powerful rationalizations: I can afford it as long as it keeps going up in value indefinitely (and it will!), I can't afford it but I'll be making more money soon, my 401(k) will never lose value so I'll be OK, or the generic "It'll all work out."

    In other words, it's another one of those cognitive biases upon which our entire economic system is based. We invest because we think we're smart enough to do it without real risk and we buy under the assumption that we'll come into the means to pay in the future.


    In early 2008 I wrote the following in the wake of the spree-killing-of-the-week at Northern Illinois University that left six dead and eighteen wounded (such an insignificant number on the contemporary scale of random American gun violence that, admit it, you've already forgotten about it):

    Nearly every news item about the NIU gunman has quoted the DeKalb police chief, who noted that friends thought The Gunman’s behavior became “erratic” in the weeks leading up to the shooting. Pure hindsight bias, of course. Let’s say that instead of going on a killing spree, he simply went about his normal day. If you asked all of his friends today “Have there been any changes in This Guy’s behavior?” they would be highly unlikely to note anything or offer any serious concerns. However, knowing that he seemingly came unhinged and shot 20-some people, small (or perhaps even imagined) deviations in his behavior are impregnated with meaning. Every email, every phone call that didn’t get returned, and every day he showed up to work 3 minutes late suddenly becomes a “sign,” obvious harbingers of what was to come.

    Hindsight bias is the kind of thing freshman psych majors learn but the media simply can't grasp. So I am unsurprised to say the least that we see much of the same "logic" throughout the reporting on the Fort Hood shooting. The shooter is clearly an individual who had a lot of issues and as we learn more, it may turn out that he threw up some red flags that should have earned the attention of his superiors. For the moment, though, we're getting a steady dose of ominously remembered conversations – and worse yet, second- and third-hand conversations – from a media anxious to hitch a ride on the USS Conjecture. Take this example of Pulitzer Prize-caliber journalism on CNN:

    Nidal Hasan's family describes him as a good American, but several people who knew Hasan in his years at this Maryland military university say the high-ranking Army officer expressed extremist Islamic views. One says Hasan openly pledged allegiance not to the United States but to the Quran, and when asked of the constitution was a brilliant document simply responded no, not particularly.

 Our sources asked not to be identified because of the ongoing investigation, and the investigators wouldn't comment on the details they offered.

    Whatever "expressed extremist Islamic views" means, to hear the Anonymous Sources Who Knew Him over the last week he appears to have been doing it 24-7. Could that be because a group not known for their sympathy toward and understanding of Islam is suddenly remembering everything about his religion as an expression of extremist fervor? Take for example the claim that he "openly pledged allegiance not to the United States but to the Quran." Here is the actual exchange:

    "Is your allegiance to Sharia law or the United States?" students once challenged Hasan, the source said. "Sharia law," Hasan responded, according to the source.

    Hmm. Is that a sign of extremism? What do you think the average buzz-cut, Bible-thumping, stereotypical military type would say if he was asked, "Which is more important, God or the United States? If you had to choose just one, would you obey the Ten Commandments or the UCMJ?" If we asked Catholics whether the Vatican is more important to them than the Obama administration, what might the response be? There are literally millions of Christian fundamentalists in this country who openly profess God before country, Bible before written law. My point here is not to debate the right-or-wrong of that. My point is simply that, in context, "God before Caesar" is not an uncommon sentiment among stridently religious people inside or outside of the military. Such a sentiment would only be a red flag in hindsight after the individual did something terrible. Or is Muslim, apparently, since I doubt the military higher-ups receive many urgent warnings about people in their ranks expressing a dangerous devotion to Christianity.

    Bless you, Anonymous Sources, for conveniently providing the sound bites for the compelling "We should have known all along" narrative so preferred among the media in these situations.


    Like an episode of Law & Order, this entry could be described as "ripped from the headlines." The current state of our nation's financial system is shaping up to be an exercise in moral hazard.

    The concept is simple: people (and organizations) act differently when they believe they will be protected from the consequences of their actions. But there are rarely explicit guarantees to that effect; this amounts to an information asymmetry in which I know that you'll let me off the hook even if you think you won't.

    A common example is found in the world of international aid. Rich Western Country gives Poor Dirty Country a giant check and a set of instructions: "Spend this on A, B, and C or else." Now, the kleptocrat in charge of PDC knows damn well that this is an idle threat. So he buys a gold-plated 737. RWC says "You failed to do A, B, or C. No more checks." But the checks come anyway for any number of reasons: guilt, concerns that PDC will buddy up with a country hostile to western interests, or emotional appeals about starvation and poverty and AIDS and sadness. "Benchmarks" are never met. The flow of money never stops. The money never gets spent on anything productive. Under the circumstances, how could we expect otherwise? Mr. Kleptocrat is reacting as all humans do to an environment in which the risks are manipulated in his favor.

    Of course a good portion of our current financial turmoil is based on a moral hazard. For every stern-faced lecture from The Fed or Chimpy about how There Will Be No Bailout, there is always a bailout. It is difficult to convincingly threaten Fannie Mae and Freddie Mac just a few months after Uncle Fed served up a quarter-trillion dollar bailout for Bear Stearns. Remember that? Everyone on Wall Street sure does.

    While the government is not above making examples out of smaller financial entities like IndyMac (a large bank, but far from an integral component of the world of finance), investment banks, underwriters, and large mortgage guarantors – Freddie and Fannie – are happy to play fast and loose with Other People's Money. Maybe they sweat a little more when they see FDIC take over a bank, but they know goddamn well that their time will never come. Congress and the President will saber-rattle, talk big, and lecture like a humorless hall monitor but they will be there with the bailout when things go to hell.

    The Fed already created a situation ripe for abuse when they agreed to let mortgage lenders trade shitty, insolvent subprime paper for cold hard cash. That's a pretty sweet deal, eh? The Fed (i.e., the public) takes on worthless past-due mortgages and the lenders take on billions in cash. As usual, and as we'll shortly see again with Freddie and Fannie, the profits belong solely to the stockholders but the risk (i.e., the losses) belongs to all of us. It's socialism for Wall Street and hard-knocks capitalism for the rest of us. Fannie's executives earn $10-$13 million per year to risk someone else's money with full confidence that we will pay the tab when they fail.

    And people wonder without a hint of irony why we ended up in this mess.

    Oh, not everything is rosy from the investors' perspective. Bear Stearns stockholders certainly felt the pain of an 18-month free-fall from $170 to $2. Fannie and Freddie investors are walking funny these days as well. But in the long-term (which is, in my humble view, the only rational way to look at stocks) they will be just fine. If anything, they will benefit from an extended opportunity to buy cheap stock in companies that Uncle Sam will not allow to fail.

    In a normal country, the government would insist on a restrictive set of regulations and caveats to go along with the bailout checks or dispense with the charade of private ownership altogether and simply nationalize Freddie, Fannie, and the other insolvent big-shots. But the financial sector doesn't believe in big government's rules, just it's cash. If the situation rights itself – as it did after the massive S&L bailout in the 1980s – you can guarantee that we'll be repeating it endlessly in the future. It's like being sent into a casino with someone else's money and two simple rules: win, and the money's yours. Lose, and the debts are on the house. Gee, what could go wrong?


    Let's play a game, courtesy of Nobel Laureate Daniel Kahneman and Amos Tversky. It's more fun if you answer honestly. You must pick one of these two choices:

    A: A sure gain of $250
    B: A 30% chance to gain $1000 and a 70% chance to gain nothing

    Now pick one of these two:

    C: A sure loss of $750
    D: A 70% chance to lose $1000 and a 30% chance to lose nothing

    Kahneman and Tversky conducted experiments and found that 84% of respondents in the first scenario chose A, whereas in the second 87% chose D. Classic economic theory (expected utility) would suggest choosing B and D. In the first problem, the expected utility would be A = $250 and B = $300 (30% of $1000). In the second problem, C = -$750 and D = -$700. So why do people get it "right" in the second problem but not the first?

    Well, Kahneman and Tversky developed Prospect Theory, essentially replacing Expected Utility Theory, winning fame and fortune in the process. I won't pretend to do it justice here; what it essentially means (note that both men are psychologists, not economists) is that people are risk averse when confronted with gains and risk seeking when gambling with losses. We prefer the sure thing, even though it's smaller, when we can gain ("One in the hand is two in the bush") but are willing to gamble a larger loss for the chance to lose nothing.
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    This is why in the stock market, for example, people sell very quickly when their investments are up (~20% profit) but hold onto bad investments for years, riding them to 80-90% losses in some cases, waiting for things to turn around.

    And now the point.

    Let's take this out of the realm of economic decision-making and into the realm of social issues. Kahneman and Tversky did. In a second experiment, they ask participants to imagine that a new virus attacks Asia and the CDC must prepare for an outbreak in the U.S. which is predicted (assume for a moment that it can be predicted accurately) to kill 600 people. They have two potential plans, and they conduct opinion polling to see how the public will react. The first test subjects saw these two choices:

    A: 200 people will be saved
    B: A 1/3 chance that all 600 people will be saved but a 2/3 chance that no one will be saved.

    A second group saw different options:

    C: 400 people will die
    D: A 1/3 chance that no one will die and a 2/3 chance that 600 people will die

    72% chose A and 78% chose D. But literally nothing has changed. These are the exact same options, worded differently: 200 live and 400 die in A or C, while there is a 2/3 chance that everyone dies in B and D. Regarding social/moral/political questions like this, framing is stupendously important. Although the odds are the same, "200 people will live" triggers the cognitive bias in favor of certainty whereas "400 people will die" activates risk averse thinking.

    So, let's apply this to the deeply-held conviction by McCain, Lieberman, and their followers that we should double down in Iraq. What these people are doing is gravitating toward choice "D" in the last problem: a small chance that things will work out perfectly and a large chance that things will go completely to shit and get far worse. This is preferred to "C", which is cutting our current (and more importantly, certain) losses. It doesn't matter that there's only a 5% chance that Iraq will turn into an idyllic paradise of stability. Our cognitive wiring suggests that even a glimmer of hope is enough.
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    The average person will take the Hail Mary pass, risking a huge loss for a miniscule chance at total victory, over a smaller but certain loss any day.


    Stop! This isn't a re-post from Wednesday. It's new. I swear. I'm doing them back-to-back because the names are so similar. But other than the root noun the two ideas have little in common.

    Historical analysis often engages in lengthy searches for explanations of favorable outcomes. Take the Cold War as an example. There is no shortage of explanations for why World War III didn't happen and why we didn't all die in a nuclear holocaust a thousand times over. Take your pick – mutually assured destruction, skillful diplomacy, Ronald Reagan's mighty persona, the power of vast international alliances, credible first-strike, credible second-strike, and so on. Maybe, although we can't say with certainty, we just got really fucking lucky. Maybe we all should have been roasted to a crisp. Maybe there was a 99% chance of nuclear war breaking out under the given conditions and we were just very fortunate to have the other 1% bear out in reality. Other than Robert McNamara, I haven't heard too many thinkers come to this conclusion.

    The reason, at least in part, is the Survivor's Bias – the tendency to overestimate the odds of success in light of a successful outcome. We managed to avoid global nuclear annihilation, so we reason that some policy ("deterrence!") was protecting us all along. The problem is that if we ever find ourselves in another similar situation, we will be wildly overconfident in our ability to achieve the same favorable outcome using the same policies. In reality, those policies may have been irrelevant. In a nuclear stare-down with China, deterrence might not work; we don't even know that it worked the first time.

    Think of it this way: you're playing roulette, and you bet every penny you own on 14. You chose 14 because you developed an elaborate formula (your birthday divided by ambient humidity times the square root of David Ortiz's on-base percentage) and it gave you that number. The wheel spins and 14 is the winner. You're ecstatic. But instead of taking your winnings and going home, you significantly overestimate the odds of the outcome you just received. "My system," you tell the assembled throng of Social Security pensioners, hookers, and ex-felons, "made victory a near certainty." You play a second time and find out the truth about the odds, namely that they are 1:38 – about 2%. You just got lucky.

    Sometimes, rather than finding some justification for our success, we change our view of the odds. The odds couldn't have been so bad after all – how else can the success be explained? For example, the odds of a borderline-insane stripper writing an Oscar-winning screenplay are astronomical. Yet in light of Sunday's awards (and thanks to dozens of rags-to-riches fluff stories in the news) I bet there are an awful lot of waiters, baristas, hookers, and overall louts in Hollywood telling themselves "See? It can be done. If this idiot could make it, it can't be that hard. I can make it!" Mathematically, you can't. Sorry. The odds are horrendous. This person is simply one in a million, and her "one" coming up big does not mean that the odds of it happening were anything but abysmal.

    Being pessimistic creatures by nature, of course we do the exact opposite on occasion and imagine the odds to be much worse than they really are. We do have a tendency to let success go to our heads quickly, though, affecting our confidence going forward and our retrospective judgment.


    Lo and behold, I was planning to start a new series this week and current events (if we can so euphemistically label mass murder) provide a picture-perfect example. But first let's talk about what hopefully will be an interesting series.

    Cognitive biases are patterns of deviation from rational judgment that occur under a given set of conditions. It's an event or scenario that warps your judgment, which would be sound (or less unsound) otherwise. One reason I find them so interesting is that, unlike logical fallacies, they affect everyone and do so subconsciously. I see flawed logic largely as a matter of brainpower; as intelligence declines, the propensity to make arguments that make no sense increases. Cognitive biases sneak up on you. They're almost like our brain's way of rebelling against us, and they can seriously F your S up.

    Let's start with Hindsight Bias, a.k.a. the "I Knew It All Along" phenomenon. It is the tendency to view what has already happened as more likely without realizing that retrospective knowledge of the outcome is affecting one's judgment (Plous 1993).

    In short, humans have a very difficult time objectively evaluating how information about an outcome affects their memories. Take a simple example like the Super Bowl. If someone asked before the game, 'What are the odds of a Giants victory?' you'd say x. If I asked you today, 'What did you think were the odds of a Giants victory?' you'd say x+n. Knowing the outcome affects how you recall your estimate the odds in hindsight. Ample research (let me know if you care about a list of academic citations, which I'm happy to provide) shows this phenomenon in buying decisions, elections, medical diagnoses, foreign affairs, and more.

    Cue the news.

    Nearly every news item about the NIU gunman has quoted the DeKalb police chief, who noted that friends thought The Gunman's behavior became "erratic" in the weeks leading up to the shooting. Pure hindsight bias, of course. Let's say that instead of going on a killing spree, he simply went about his normal day. If you asked all of his friends today "Have there been any changes in This Guy's behavior?" they would be highly unlikely to note anything or offer any serious concerns. However, knowing that he seemingly came unhinged and shot 20-some people, small (or perhaps even imagined) deviations in his behavior are impregnated with meaning. Every email, every phone call that didn't get returned, and every day he showed up to work 3 minutes late suddenly becomes a "sign," obvious harbingers of what was to come. You simply cannot ask people "Did John Doe act strangely or differently last week?" right after he cracks and kills half a dozen people. And himself. The way to get useful information would be to wait (get some distance from the events) and make a conscious effort to question whether the "erratic" behaviors really happened and are being blown out of proportion.

    In the wake of such a jarring series of events, that's a lot harder than it seems.