57 Cognitive Biases That Screw Up How We Think

People aren't as rational as we would like to think. From attentional bias — where someone focuses on only one or two of several possible outcomes — to zero-risk bias — where we place too much value on reducing a small risk to zero — the sheer number of cognitive biases that affect us every day is staggering. Understanding these biases is key to suppressing them — and needless to say, it is good to try to be rational in most cases. How else can you have any sort of control over investments, purchases, and all other decisions that you make in your life? To convey the breadth of cognitive biases, we've picked out 57 of the most notable ones from a much longer list on Wikipedia. http://en.wikipedia.org/wiki/List_of_cognitive_biases Attentional bias When someone focuses on only one or two choices despite there being several possible outcomes. Availability heuristic Where people overestimate the importance of information that is available to them. One example would be a person who argues that smoking is not unhealthy on the basis that his grandfather lived to 100 and smoked three packs a day, an argument that ignores the possibility that his grandfather was an outlier. Backfire effect When you reject evidence that contradicts your point of view or statement, even if you know it's true. Bandwagon effect The probability of one person adopting a belief increases based on the number of people who hold that belief. This is a powerful form of groupthink. Belief bias A bias where people make faulty conclusions based on what they already believe or know. For instance, one might conclude that all tiger sharks are sharks, and all sharks are animals, and therefore all animals are tiger sharks. Bias blind spots If you fail to realize your own cognitive biases, you have a bias blind spot. Everyone thinks they're not as biased as people may think, which is a cognitive bias itself. Choice-supportive bias A bias in which you think positive things about a choice once you made it, even if that choice has flaws. You may say positive things about the dog you just bought and ignore that the dog bites people. Clustering illusion This is the tendency to see streaks or clusters in random events. A gambler after watching a red come up multiple times in a row on a roulette table may erroneously conclude that red is hot. In a related bias, known as cognitive bias, the gambler may conclude that black is particularly likely to come up since it hasn't come up in awhile. In fact, the results are always random. Confirmation bias A tendency people have to believe certain information that confirms what they think or believe in. Conservatism bias Where people believe prior evidence more than new evidence or information that has emerged. People were slow to accept the fact that the earth was round because they tended to believe earlier information that it was flat. Curse of knowledge When people who are smarter or more well informed can not understand the common man. For instance, in the TV show "The Big Bang Theory" it's difficult for scientist Sheldon Cooper to understand his waitress neighbor Penny. Decoy effect A phenomenon in marketing where consumers have a specific change in preference between two choices after being presented with a third choice. Denomination effect People are less likely to spend large bills than their equivalent value in small bills or coins. Duration neglect When the duration of an event doesn't factor enough into a valuation. For instance we may remember momentary displeasure as strongly as protracted displeasure. Empathy gap Where people in one state fail to understand people in another state. If you are happy you can't imagine why people would be unhappy. When you are not sexually aroused, you can't understand how you act when you are sexually aroused. Frequency illusion Where a word, name or thing you just learned about suddenly appears everywhere. Now that you know what that SAT word means, you see it in so many places! Galatea Effect Where people succeed because they think they should. Halo effect Where we take one positive attribute of someone and associate it with everything else about that person or thing. Hard-Easy bias Where everyone is overconfident on easy problems and not confident enough for hard problems. Herding People tend to flock together, especially in difficult or uncertain times. Hindsight bias The tendency to see past events as predictable. "I knew all along Philip Phillips would win American Idol." Sure you did... Hyperbolic discounting The tendency for people to want an immediate payoff rather than a larger gain later on. Most people would rather take $5 now than $7 in a week. Ideometer effect Where an idea causes you to have an unconscious physical reaction, like a sad thought that makes your eyes tear up. This is also how Ouija boards seem to have minds of their own. Illusion of control The tendency for people to overestimate their ability to control events, like when a sports fan thinks his thoughts or actions had an effect on the game. Illusion of validity When weak but consistent data leads to confident predictions. Like one commenter noted on the MIT admissions blog: Why is MIT's admissions process better than random? Say you weeded out the un-qualified (the fewer-than-half of applicants insufficiently prepared to do the work at MIT) and then threw dice to stochastically select among the remaining candidates. Would this produce a lesser class? Information bias The tendency to seek information when it does not affect action. More information is not always better. Inter-group bias We view people in our group differently from how see we someone in another group. Irrational escalation Investing more money or resources into something based on prior investment, even if you know it's a bad one. "I already have 500 shares of Lehman Brothers, let's buy more even though the stock is tanking." Less-is-more effect With less knowledge, people can often make more accurate predictions. Negativity bias The tendency to put more emphasis on negative experiences rather than positive ones. People with this bias feel that "bad is stronger than good" and will perceive threats more than opportunities in a given situation. This leads toward loss aversion. Observer-expectancy effect Our expectations unconsciously influence how we perceive an outcome. Researchers, for example, looking for a certain result in an experiment, may inadvertently manipulate or interpret the results to reveal their expectations. That's why the "double-blind" experimental design was created for the field of scientific research. Omission bias The tendency to judge harmful actions as worse than equally harmful inactions. For example, we consider it worse to crash a car while drunk than to let one's friend crash his car while drunk. Ostrich effect The decision to ignore dangerous or negative information by "burying" one's head in the sand, like an ostrich. Outcome bias Judging a decision based on the outcome over the quality of the decision when it was made. This is not accounting for the role luck plays in outcomes. Overconfidence We are too confident about our abilities, and this causes us to take greater risks in our daily lives. Overoptimism When we believe the world is a better place than it is, we aren't prepared for the danger and violence we may encounter. The inability to accept the full breadth of human nature leaves us vulnerable. Pessimism bias This is the opposite of the overoptimism bias. Pessimists over-weigh negative consequences with their own and others' actions. Placebo effect A self-fulfilling prophecy, where belief in something causes it to be effective. This is a basic principle of stock market cycles. Planning fallacy The tendency to underestimate how much time it will take to complete a task. Post-purchase rationalization Making ourselves believe that a purchase was worth the value after the fact. Pro-innovation bias When a proponent of an innovation tends to overvalue its usefulness and undervalue its limitations. Procrastination Deciding to act in favor of the present moment over investing in the future. Reactance The desire to do the opposite of what someone wants you to do, in order to prove your freedom of choice. Recency The tendency to weight the latest information more heavily than older data. Reciprocity The belief that fairness should trump other values, even when it's not in our economic and/or other interests. Regression bias People take action in response to extreme situations. Then when the situations become less extreme, they take credit for causing the change, when a more likely explanation is that the situation was reverting to the mean. Restraint bias Overestimating one's ability to show restraint in the face of temptation. Salience Our tendency to focus on the most easily-recognizable features of a person or concept. Seersucker Illusion Over-reliance on expert advice. This has to do with the avoidance or responsibility. We call in "experts" to forecast, when in fact, they have no greater chance of predicting an outcome than the rest of the population. In other words, "for every seer there's a sucker." Selective perception Allowing our expectations to influence how we perceive the world. Self-enhancing transmission bias Everyone shares their successes more than their failures. This leads to a false perception of reality and inability to accurately assess situations. Status quo bias The tendency to prefer things to stay the same. This is similar to loss-aversion bias, where people prefer to avoid losses instead of acquiring gains. Stereotyping Expecting a group or person to have certain qualities without having real information about the individual. This explains the snap judgments Malcolm Gladwell refers to in "Blink." Survivorship bias An error that comes from focusing only on surviving examples, causing us to misjudge a situation. For instance, we might think that being an entrepreneur is easy because we haven't heard of all of the entrepreneurs who have failed. It can also cause us to assume that survivors are inordinately better than failures, without regard for the importance of luck or other factors. Tragedy of the commons We overuse common resources because it's not in any individual's interest to conserve them. This explains the overuse of natural resources, opportunism, and any acts of self-interest over collective interest. Unit bias We believe that there is an optimal unit size, or a universally-acknowledged amount of a given item that is perceived as appropriate. This explains why when served larger portions, we eat more. Zero-risk bias The preference to reduce a small risk to zero versus achieving a greater reduction in a greater risk. This plays to our desire to have complete control over a single, more minor outcome, over the desire for more — but not complete — control over a greater, more unpredictable outcome. Read more about zero-risk bias. That's just behavioral biases. There are all sorts of weird things in your head. Read more: http://www.businessinsider.com/cognitive-biases-2013-8

These 10 Everyday Activities Are Slowly Killing You

We all want to live longer, healthier lives but there are hidden dangers all around us. Here are just a few of the tons of things we do every day that can shorten your lifespan without you knowing it. 1. Sitting Bad news for office workers. Even if you regularly exercise, long periods of inactivity are unhealthy. A study published in 2012 in the journal BMJ Open estimated that individuals who reduced excessive sitting to less than three hours a day could add two years to their life expectancy. 2. Sleeping too much Sleeping too little is of course bad for your health (and makes you gain weight), but sleeping too much can be equally harmful. A review of sleep studies showed that people who slept more than nine hours a night were at a 41% higher risk for heart disease than those who slept seven to eight hours a night. 3. Staring at a screen Research published in the Journal of the American College of Cardiology suggests that spending more than four hours a day in front of a screen, like watching TV or surfing the Internet, can increase risk of heart attack and stroke by as much as 113%. Another study published in BMJ Open estimated that reducing screen time to less than two hours a day, individuals could add almost 1.4 years to their life expectancy. 4. Taking medication for non life-threatening illnesses Taking medication for things like insomnia or anxiety could lower some people's life expectancy. In a 12-year study, published in the Canadian Journal of Psychiatry, scientists found that individuals not taking such medications had about a 5% lower mortality rate than those taking medication. 5. Lacking a sense of humor Laughter has a long list of health benefits according to the Mayo Clinic — it helps boost the immune system, reduces stress, and provides an emotional release. Laughing also burns calories. 6. A long commute Not only does commuting take up lots of time on a daily basis, it may also be taking time away from your total life span. Unpublished work presented at the annual meeting of the Association of American Geographers suggested that people with commutes longer than 30 minutes die earlier than others. Long commutes mean less time for exercise and sleep — both of which contribute to a longer and healthier life. 7. Stressing out We've all heard that stress can be harmful to our health and immune system, but research published in the Proceedings of The National Academy of Sciences suggests it can actually damage our very DNA. Compared to non-stressed people, study participants with chronic stress had shorter telomeres — the regions responsible for protecting and connecting the ends of DNA strands, so our genes don't degrade over time. 8. Not having sex Having sex not only relieves stress, it burns calories and may even increase your life span. A Duke University study found that women with enjoyable sex lives lived almost eight years longer. Another study, in the journal BMJ, suggests that men who reported a higher frequency of orgasms had a 50% reduction in mortality. 9. Eating Poorly Things like processed foods, too much red meat, and not enough fresh fruit and vegetables all can contribute to serious health problems. Excessive red meat consumption contributed to higher cardiovascular disease and cancer mortality, according to a study in the journal Internal Medicine. 10. Being anti-social Isolation and loneliness can take a toll on your body in the same way excessive stress does. The MacArthur Study of Successful Aging demonstrated that people who rated themselves highly valuable in their friends' and family's lives were more likely to live longer than those who rated themselves lower. Read more: http://www.businessinsider.com/activities-that-could-be-killing-you-2013-9