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Video transcript

what do you think is more likely someone dying from a shark attack or someone dying from a fireworks accident to answer that question you have to make a decision in decision-making we make a judgment about the desirability or in this case the probability of some outcome if you're like most people you used a heuristic or mental shortcut to make that decision you may have thought about all the instances in which you've read about shark attacks in the news vs. fatal accidents involving fireworks that method is called the availability heuristic you're using examples that readily come to mind or easily available in your memory most of the time that's a very helpful shortcut but unfortunately are easily memorable experiences don't always match the real state of the world in this case even though you've probably read more stories about shark attacks the risk of dying from one is about one in 3.7 million whereas the risk of dying from a fireworks accident is about one and 340,000 a much higher risk but usually much less publicized another heuristic that can lead us astray in decision making is the representativeness heuristic in this case we judge the probability of an event based on our existing prototype or general concept of what is typical for example say I tell you that a person named Linda is thirty years old single outspoken and very bright she majored in philosophy and as a student she participated in anti-nuclear demonstrations and organizations that fought discrimination now which do you think is more likely that Linda is a bank teller or that Linda is a feminist bank teller if you're like most people you answered that she is more likely to be a feminist bank teller even if you don't know any feminists or even anyone who's exactly like our imaginary Linda she fits your prototype of how a feminist would act she is representative of a feminist and most of the time the representativeness heuristic can help us make quick judgments however in this case it leads us to something called a conjunction phallus see which is when people think that the co-occurrence of two instances being a feminist and being a bank teller is more likely than a single one just being a bank teller because statistically speaking there are a lot more bank tellers then there are feminist bank tellers so it's actually more likely that she's just a bank teller even though your instincts are telling you otherwise now be careful not to get confused between availability and representativeness when using the availability heuristic you're thinking of actual memories that can come to your mind that are available in your head with representativeness you're not necessarily thinking of exact memories you're thinking of a prototype of this idea okay so we've talked about some heuristics that guide our decision-making processes so now let's talk about some biases that prevent us from making correct decisions or from changing our decisions once they're made one bias is overconfidence which is just our tendency to be more confident than correct you may have experienced this going into a test when you thought you'd ace it but then you didn't know a lot of the information and this overconfidence could be due to fluency while you're studying or the ease of processing in other words things might have felt really easy when you were studying in your room but if you never tried to test yourself to see if you really knew the answers then you might overestimate your ability to produce answers when you need to you may have also experienced overconfidence if you've ever been in an argument when you're positive you're right until someone shows proof that you're not if you don't change your mind after you get this new information though then you're falling prey to the bias of belief perseverance this happens a lot around election time whenever people hear something they don't like about their favorite candidate they often ignore it or rationalize it away now this bias is slightly different than something called the confirmation bias which is when you actively seek out only the information that confirms your existing beliefs so in our election example you would be exhibiting confirmation bias if you only read stories that talk to how wonderful your favorite candidate was but you'd be exhibiting belief perseverance if you learned about but then ignored information that you didn't like about your candidate another factor that can affect decision-making is framing which is just how you present the decision for example suppose I tell you there is a disease about to strike the population that will kill 600 people however there are two options for programs to combat this disease if you pick option a then there's a 100% chance that exactly 200 people will be saved if you pick option B there's a one-third chance that all 600 people will be saved and a two-thirds chance that nobody will be saved which do you want to pick okay now try this one the same disease is coming through and you again have two options if you pick option A then there's a 100% chance that exactly 400 people will die if you pick option B then there is a one-third chance that no one will die and a two-thirds chance that 600 people will die now which option do you want to pick if you're like most people when the decision is framed in terms of how many people will be saved you're more likely to pick option a save 200 people for sure but when the decision is framed in terms of how many people will die you're more likely to pick option B to avoid killing 400 people for sure even though saving 200 people is the exact same thing as letting 400 people die in this example it seems better to pick that option when it's framed or presented in terms of how many people will be saved likewise it seems better to pick an option that offers a chance of no people dying rather than to risk not saving some people so hopefully this doesn't make you paranoid but our decisions are not quite as black-and-white or even as consistent as we think they are so next time you have to judge something try to take a step back and consider all the factors that could be influencing your decision you