Can people differentiate what they know from what they do not? Several lines of research suggest that people are not always accurate judges of their knowledge and often overestimate how much they know. Research on overconfidence finds that people commonly judge the accuracy of their judgments too favorably and typically overestimate how well they perform everyday tasks relative to other people. Work on the illusion of explanatory depth demonstrates that participants tend to think they have a better understanding of how objects work (e.g., a ballpoint pen) than they can demonstrate when that understanding is put to the test. At times, people even claim knowledge they cannot possibly have, because the object of their knowledge does not exist, a phenomenon known as overclaiming. For example, in the late 1970s, nearly a third of American respondents expressed an opinion about the “1975 Public Affairs Act” when asked about it directly, even though the act was a complete fiction. Approximately a fifth of consumers report having used products that are actually nonexistent. More recent research has asked participants to rate their familiarity with a mix of real and nonexistent concepts, names, and events in domains such as philosophy, life sciences, physical sciences, and literature. Participants reported being familiar with the real items but also, to a lesser degree, with the nonexistent ones. […] What underlies assertions of such impossible knowledge? We found that people overclaim to the extent that they perceive their personal expertise favorably. […] A sizable body of work on how people evaluate their own knowledge suggests that they rely not only on a direct examination of their mental contents but also on a feeling of knowing. Notably, a feeling of knowing is often only weakly predictive of actual knowledge and appears to be informed, at least in part, by top-down inferences about what should be or probably is known. We theorized that such inferences are drawn from people’s preconceived notions about their expertise, inducing a feeling of knowing that then prompts overclaiming. [Psychological Science | PDF]
Decades of research have shown that humans are so-called cognitive misers. When we approach a problem, our natural default is to tap the least tiring cognitive process. Typically this is what psychologists call type 1 thinking, famously described by Nobel Prize–winning psychologist Daniel Kahneman as automatic, intuitive processes that are not very strenuous. This is in contrast to type 2 thinking, which is slower and involves processing more cues in the environment. Defaulting to type 1 makes evolutionary sense: if we can solve a problem more simply, we can bank extra mental capacity for completing other tasks. A problem arises, however, when the simple cues available are either insufficient or vastly inferior to the more complex cues at hand. Exactly this kind of conflict can occur when someone chooses to believe a personal opinion over scientific evidence or statistics. [Scientific American]
What happens to us as we accrue knowledge and experience, as we become experts in a field? Competence follows. Effortlessness follows. But certain downsides can follow too. We reported recently on how experts are vulnerable to an overclaiming error – falsely feeling familiar with things that seem true of a domain but aren’t. Now a new paper in the Journal of Experimental Social Psychology explores how feelings of expertise can lead us to be more dogmatic towards new ideas. [BPS]
Past research showed that people accumulate more knowledge about other people and objects they like compared to those they dislike. More knowledge is commonly assumed to lead to more differentiated mental representations; therefore, people should perceive others they like as less similar to one another than others they dislike. We predict the opposite outcome based on the density hypothesis; accordingly, positive impressions are less diverse than negative impressions as there are only a few ways to be liked but many ways to be disliked. Therefore, people should perceive liked others as more similar to one another than disliked others even though they have more knowledge about liked others. Seven experiments confirm this counterintuitive prediction and show a strong association between liking and perceived similarity in person perception. [Journal of Experimental Social Psychology]
Statisticians love to develop multiple ways of testing the same thing. If I want to decide whether two groups of people have significantly different IQs, I can run a t-test or a rank sum test or a bootstrap or a regression. You can argue about which of these is most appropriate, but I basically think that if the effect is really statistically significant and large enough to matter, it should emerge regardless of which test you use, as long as the test is reasonable and your sample isn’t tiny. An effect that appears when you use a parametric test but not a nonparametric test is probably not worth writing home about. A similar lesson applies, I think, to first dates. When you’re attracted to someone, you overanalyze everything you say, spend extra time trying to look attractive, etc. But if your mutual attraction is really statistically significant and large enough to matter, it should emerge regardless of the exact circumstances of a single evening. If the shirt you wear can fundamentally alter whether someone is attracted to you, you probably shouldn’t be life partners. […] In statistical terms, a glance at across a bar doesn’t give you a lot of data and increases the probability you’ll make an incorrect decision. As a statistician, I prefer not to work with small datasets, and similarly, I’ve never liked romantic environments that give me very little data about a person. (Don’t get me started on Tinder. The only thing I can think when I see some stranger staring at me out of a phone is, “My errorbars are huge!” which makes it very hard to assess attraction.) […] I think there’s even an argument for being deliberately unattractive to your date, on the grounds that if they still like you, they must really like you. [Obsession with Regression]
The ratio between the body circumference at the waist and the hips (or WHR) is a secondary sexual trait that is unique to humans and is well known to influence men’s mate preferences. Because a woman’s WHR also provides information about her age, health and fertility, men’s preference concerning this physical feature may possibly be a cognitive adaptation selected in the human lineage. […] We analyzed the WHR of women considered as ideally beautiful who were depicted in western artworks from 500 BCE to the present. These vestiges of the past feminine ideal were then compared to more recent symbols of beauty: Playboy models and winners of several Miss pageants from 1920 to 2014. We found that the ideal WHR has changed over time in western societies: it was constant during almost a millennium in antiquity (from 500 BCE to 400 CE) and has decreased from the 15th century to the present. Then, based on Playboy models and Miss pageants winners, this decrease appears to slow down or even reverse during the second half of the 20th century. The universality of an ideal WHR is thus challenged, and historical changes in western societies could have caused these variations in men’s preferences. [PLOS]
This research examines the role of alcohol consumption on self-perceived attractiveness. Study 1, carried out in a barroom (N= 19), showed that the more alcoholic drinks customers consumed, the more attractive they thought they were. In Study 2, 94 non-student participants in a bogus taste-test study were given either an alcoholic beverage (target BAL [blood alcohol level]= 0.10 g/100 ml) or a non-alcoholic beverage, with half of each group believing they had consumed alcohol and half believing they had not (balanced placebo design). After consuming beverages, they delivered a speech and rated how attractive, bright, original, and funny they thought they were. The speeches were videotaped and rated by 22 independent judges. Results showed that participants who thought they had consumed alcohol gave themselves more positive self-evaluations. However, ratings from independent judges showed that this boost in self-evaluation was unrelated to actual performance. [British Journal of Psychology | PDF]
Last year, Kennedy, a 67-year-old neurologist and inventor, did something unprecedented in the annals of self-experimentation. He paid a surgeon in Central America $25,000 to implant electrodes into his brain in order to establish a connection between his motor cortex and a computer.
Neurotechnologies are “dual-use” tools, which means that in addition to being employed in medical problem-solving, they could also be applied (or misapplied) for military purposes. The same brain-scanning machines meant to diagnose Alzheimer’s disease or autism could potentially read someone’s private thoughts. Computer systems attached to brain tissue that allow paralyzed patients to control robotic appendages with thought alone could also be used by a state to direct bionic soldiers or pilot aircraft. And devices designed to aid a deteriorating mind could alternatively be used to implant new memories, or to extinguish existing ones, in allies and enemies alike. […] “The potential to do something like mind reading is going to be available sooner rather than later.” More to the point, “It’s going to be possible within our lifetimes.” [Foreign Policy]
People with a certain type of gene are more deeply affected by their life experiences, a new study has revealed. The findings challenge traditional thinking about depression, showing what might be considered a risk gene for depression in one context, may actually be beneficial in another. [EurekAlert]
By licking a wound it heals faster — this is not simply popular belief, but scientifically proven. Our saliva consists of water and mucus, among other things, and the mucus plays an important role. It stimulates white blood cells to build a good defense against invaders. [Lunatic Laboratories]
Blood is a bodily fluid in humans and other animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells. […] In vertebrates, it is composed of blood cells suspended in blood plasma. Plasma, which constitutes 55% of blood fluid, is mostly water (92% by volume), and contains dissipated proteins, glucose, mineral ions, hormones, carbon dioxide (plasma being the main medium for excretory product transportation), and blood cells themselves. Albumin is the main protein in plasma, and it functions to regulate the colloidal osmotic pressure of blood. The blood cells are mainly red blood cells, white blood cells (also called leukocytes) and platelets. The most abundant cells in vertebrate blood are red blood cells. [Wikipedia]
The moles on your right arm may predict your risk of skin cancer. New research suggests that it’s specifically those with 11 moles or more on their right arms who need to care the most
Crocodiles, like some birds and aquatic mammals, may well sleep with half of their brain at a time. The researchers found that crocodiles were more inclined to sleep with one eye open when humans were present, and that the open eye was always directed towards the human.
Coffee hydrates as well as water, study says. The belief that caffeinated drinks such as coffee could cause dehydration is based on a 1928 study that demonstrated caffeine’s diuretic effect.
Chinese ice cream is different, and those differences reflect a different economic and technological context. American ice cream is mainly sold by grocery stores in large containers to be eaten at home. So the basic assumption is that people have freezers at home in which to store the ice cream. Even when ice cream is sold on-the-go, it is sold out as scoops out of those big containers. But historically in China most people did not have freezers at home, though many more of them do now. Ice cream in China is therefore usually sold by convenience stores or roadside stalls, in small packages to be eaten immediately. So rather than big vats of ice cream, it is mostly individual bars. These constraints have pushed innovation in Chinese ice cream in different directions. You can get all kinds of amazing wacky ice cream flavors in the US, but they are all delivered in mostly the same form: a tub of ice cream eaten with a spoon. Chinese ice cream innovates on form and texture more than with ingredients, with many bars featuring not just crunchy outer layers of chocolate but interior elements made of various yummy substances. The structural complexity of some ice-cream bars is so great that it’s common for the package to have a 3-D cutaway diagram to illustrate all the goodies on the inside. [Andrew Batson]
It costs as much as $4 million to open a new diner these days, compared with $500,000 to $1 million for a higher-end restaurant, because diners require so much storage space for the inventory that their large menus require.
This article examines associations between the Great Recession and 4 aspects of 9-year olds’ behavior – aggression (externalizing), anxiety/depression (internalizing), alcohol and drug use, and vandalism – using the Fragile Families and Child Wellbeing Study, a longitudinal birth cohort drawn from 20 U.S. cities (21%, White, 50% Black, 26% Hispanic, and 3% other race/ethnicity). The study was in the field for the 9-year follow-up right before and during the Great Recession (2007-2010; N = 3,311). Interview dates (month) were linked to the national Consumer Sentiment Index (CSI), calculated from a national probability sample drawn monthly to assess consumer confidence and uncertainty about the economy, as well as to data on local unemployment rates. We find that greater uncertainty as measured by the CSI was associated with higher rates of all 4 behavior problems for boys (in both maternal and child reports). Such associations were not found for girls. [Developmental Psychology]
The wedding industry has consistently sought to link wedding spending with long-lasting marriages. This paper is the first to examine this relationship statistically. We find that marriage duration is either not associated or inversely associated with spending on the engagement ring and wedding ceremony. Overall, our findings provide little evidence to support the validity of the wedding industry’s general message that connects expensive weddings with positive marital outcomes. [PDF | via Improbable]
Women initiate most divorces in the US. […] The data examine the gender of breakup for both marital and nonmarital relationships for the first time. The results show that women’s initiation of breakup is specific to heterosexual marriage. Men and women in nonmarital heterosexual relationships in the US are equally likely to initiate breakup. The results are consistent with a feminist critique of heterosexual marriage as an institution that benefits men more than women. [The Gender of Breakup in Heterosexual Couples | Abstract + Charts]
Most people own things that they don’t really need. It is worth thinking about why. […] A policy aimed at curbing luxury shopping might involve higher marginal tax rates or, as a more targeted intervention, a consumption tax. As it becomes harder to afford a Rolex, people will devote more money to pleasures that really matter. Less waste, more happiness. [Boston Review]
Business Insiders is expecting to make 65 million dollars next year. […] It employs 325 people, meaning it currently brings in roughly $132,300 in revenue per employee.BuzzFeed … $208,333 per employee […] Gawker … $211,538 per employee […] Vice … $457,500 per employee […] The New York Times Company … between $440,000 and $450,000 per employee [The Awl]
With the advent of the Internet, many U.S. metropolitan areas have seen newspaper closures due to declining revenues. This provides the researcher with an opportunity to analyze the microeconomic sources of media bias.
This article uses a large panel dataset of newspaper archives for 99 newspapers over 240 months (1990–2009).
The author found that, after controlling for the unemployment rate, the change in unemployment rate, and the political preferences of surrounding metropolitan area, conservative newspapers report 17.4% more unemployment news when the President is a Democrat rather than a Republican, before the closure of a rival newspaper in the same media market. This effect is 12.8% for liberal newspapers. After the closure, these numbers are 3.5% and 1.1%, respectively. [Journal of Media Economics]
This article examines the extent to which advertising outside of an explicit campaign environment has the potential to benefit the electoral fortunes of incumbent politicians. We make use of a novel case of non-campaign advertising, that of North Carolina Secretary of Labor Cherie Berry (R-NC), who has initiated the practice of having her picture and name displayed prominently on official inspection placards inside all North Carolina elevators. We […] find that Berry outperformed other statewide Republican candidates in the 2012 North Carolina elections. Our findings suggest that candidates can use this form of advertising to indirectly improve their electoral fortunes. [American Politics Research]
Researchers Elizabeth L. Paluck and colleagues partnered with a TV network to insert certain themes (or messages) into popular dramas shown on US TV. They then looked to see whether these themes had an effect on real world behavior, ranging from Google searches to drink-driving arrests. The study was based on three prime time Spanish-language dramas (telenovelas) which have a viewership of around 1.2 million people per week. Telenovelas are a genre similar to English-language soap operas except shorter, most lasting about a year. Into these shows, eight messages were added, ranging from health and safety (benefits of low cholesterol, dangers of drink driving) to community building (register to vote, scholarships for Hispanic students.) […] So did it work? Not really. […] There was no evidence that messages about voter registration led to increases in the number of Hispanics actually registering. Nor did Google searches for terms related to the messages increase following each broadcast. [Neuroskeptic]
How Auction Houses Orchestrate Sales for Maximum Drama [NY Times]
Experts say fakes have become one of the most vexing problems in the art market. […] Two years ago, the center, known for its work in bioengineering, encryption and nanotechnology, set about developing a way to infuse paintings, sculptures and other artworks with complex molecules of DNA created in the lab. […] The new approach, in its formative stage, would implant synthetic DNA, not the personal DNA of the artists, because of privacy issues and because a person’s DNA could conceivably be stolen and embedded, thus undermining the authority of such a marking protocol. The developers said the bioengineered DNA would be unique to each item and provide an encrypted link between the art and a database that would hold the consensus of authoritative information about the work. The DNA details could be read by a scanner available to anyone in the art industry wanting to verify an object. [NY Times]
There are approximately 900 actively working mail chutes in New York. As letters grew in size, clogging of the mail chutes became an increasing problem.
Imagine that you are imprisoned in a tunnel that opens out onto a precipice two paces to your left, and a pit of vipers two paces to your right. To torment you, your evil captor forces you to take a series of steps to the left and right. You need to devise a series that will allow you to avoid the hazards — if you take a step to the right, for example, you’ll want your second step to be to the left, to avoid falling off the cliff. You might try alternating right and left steps, but here’s the catch: You have to list your planned steps ahead of time, and your captor might have you take every second step on your list (starting at the second step), or every third step (starting at the third), or some other skip-counting sequence. Is there a list of steps that will keep you alive, no matter what sequence your captor chooses? In this brainteaser, devised by the mathematics popularizer James Grime, you can plan a list of 11 steps that protects you from death. But if you try to add a 12th step, you are doomed: Your captor will inevitably be able to find some skip-counting sequence that will plunge you over the cliff or into the viper pit. Around 1932, Erdős asked, in essence, what if the precipice and pit of vipers are three paces away instead of two? What if they are N paces away? Can you escape death for an infinite number of steps? The answer, Erdős conjectured, was no — no matter how far away the precipice and viper pit are, you can’t elude them forever. But for more than 80 years, mathematicians made no progress on proving Erdős’ discrepancy conjecture (so named because the distance from the center of the tunnel is known as the discrepancy). [Quanta]
Streaming music is officially a bigger business than physical music sales in the U.S. for the first time. If current trends continue, streaming will surpass digital download sales as the biggest single source of revenue for the music industry by next year.