Something You Should Know - Why Your Fingers Get Pruney When Wet & How to Use Online Reviews Effectively

Episode Date: February 17, 2020

What is the best way to sign-off an email? Well, it depends on what you want the outcome to be but if you re hoping for a reply, there is one sign-off that is more likely to get someone to respond. This episode begins with me revealing those magic words. http://www.businessinsider.com/best-way-to-end-an-email-2017-2 Why is your brain in your head? Why do your eyes face forward but a fish’s eyes are on the side of it’s head? These are just a few of the interesting questions about your body that I discuss with Mark Changizi. Mark is a cognitive scientist, he has a YouTube series about science (https://www.youtube.com/user/mchangizi) and he has authored some science books – one being The Vision Revolution: How the Latest Research Overturns Everything We Thought We Knew About Human Vision (https://amzn.to/2SwLNMs) Wrinkles are inevitable. However, there are things we can all do to minimize how many you get and how prominent they are. Listen as I discuss some expert advice from Good Housekeeping magazine and I’ll also reveal the best way to tell how many wrinkles you will likely get. http://www.goodhousekeeping.com/beauty/anti-aging/things-you-didnt-know-about-wrinkles When you make buying decisions, a lot of factors go into it – some you aren’t even aware of. And then there are customer reviews. Are they a could way to determine if you should buy or not buy a product? That’s what I discuss with Bart de Langhe, a behavioral scientist and a marketing professor at ESADE Business School in Barcelona, Spain and an expert on buying behavior. He has a TED talk on the subject you can watch here: https://www.youtube.com/watch?time_continue=13&v=d8TxoQWFW7E&feature=emb_logo This Week's Sponsors -Blinkist. Go to www.Blinkist.com/sysk to start your free 7 day trial and get 25% off your subscription Learn more about your ad choices. Visit megaphone.fm/adchoices

As a listener to Something You Should Know, I can only assume that you are someone who likes to learn about new and interesting things and bring more knowledge to work for you in your everyday life. I mean, that's kind of what Something You Should Know was all about. And so I want to invite you to listen to another podcast called TED Talks Daily. Now, you know about TED Talks, right? Many of the guests on Something You Should Know have done TED Talks. Well, you see, TED Talks Daily is a podcast that brings you a new TED Talk every weekday in less than 15 minutes. Join host Elise Hu.

She goes beyond the headlines so you can hear about the big ideas shaping our future. Learn about things like sustainable fashion, embracing your entrepreneurial spirit, the future of robotics, and so much more. Like I said, if you like this podcast, Something You Should Know, I'm pretty sure you're going to like TED Talks Daily. And you get TED Talks Daily wherever you get your podcasts. Today on Something You Should Know, what's the best sign off to use on an email if you want the person to reply back? Then interesting questions about the human body, like why is your brain in your head? One of the most difficult things about building a nervous system is the amount of wire that it takes to build it. So the reason the brain is in the head is it comes down to trying to save wire.

You see with your head, you hear with your head. If you want to minimize the amount of wiring that you have to use, then the best place to put the brain is right up against those sensors. Plus, the truth about wrinkles and why you get them, and the pitfalls of believing online product reviews. An additional problem with online reviews is their goals are not necessarily to evaluate the objective performance of products, but their goals may be different just to leave their opinion or to have an influence on other people or to achieve a certain incentive. All this today on Something You Should Know.

Since I host a podcast, it's pretty common for me to be asked to recommend a podcast. And I tell people, if you like Something You Should Know, you're going to like The Jordan Harbinger Show. Every episode is a conversation with a fascinating guest. Of course, a lot of podcasts are conversations with guests, but Jordan does it better than most. Recently, he had a fascinating conversation with a British woman who was recruited and radicalized by ISIS and went to prison for three years. She now works to raise awareness on this issue. It's a great conversation. And he spoke with Dr. Sarah Hill about how taking birth control not only prevents pregnancy, it can

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Fascinating intel. The world's top experts. And practical advice you can use in your life. Today, Something You Should Know with Mike Carruthers. Hi, welcome to Something You Should Know. If you're a regular listener, you can probably tell that my voice is a little off today. I caught a cold. My son had a cold, a pretty bad one, and I thought I escaped it. And on the last day that he had it, basically, I felt it coming on. And here it is, which is why I sound a bit stuffy and gruff.

But we persevere, and we start today with the best way to sign off on an email. I don't know how you sign off on your emails. Some experts say you don't need to. There's no sign-off necessary. Other etiquette experts say the word best is the best way. But it really depends on what your goal is. And if the goal is to get a person to respond to what you just wrote, the best sign-off is thanks in advance.

In looking at 350,000 email threads, here are the common sign-offs and their response rates. Thanks in advance had a response rate of 65.7%. Just thanks all by itself. Thanks had a response rate of 63%. Thank you had a response rate of 57.9. Cheers, the response rate was 54.4. Kind regards came in at 53.9. Regards had a

response rate of 53.5. Best regards had a response rate of 52.9. and just the word best by itself had a response rate of 51.2. So to increase your chances of getting the response you ask for, it's best to sign off with thanks in advance. And that is something you should know. Have you ever thought about, and wondered why, for example, our eyes face forward rather than be on the sides of our head? Or why your brain is located in your head, which is a pretty fragile place to put it? Or why we have color vision when some other animals don't. Interesting questions, and they're some of the ones we're about to tackle with Mark

Changhisi. Mark is a cognitive scientist who has a YouTube series about science, and there's a link to it in the show notes. He's also authored some science books, one being The Vision Revolution, How the Latest Research Overturns Everything We Thought We Knew About Human Vision. Hi Mark, welcome. One being The Vision Revolution, how the latest research overturns everything we thought we knew about human vision. Hi Mark, welcome. Great to be here, Mike. So let's start by talking about color vision and why we have color vision and some other animals don't. Why is that?

We primates, us apes and the other primates, some of the other primates have color vision. And really what we have that's above and beyond your bunny, rabbit, and dog, and horses is we have red-green because they only have grayscale, white to black, and then they have blue-yellow. Blue and yellow are opposites, and so that's the second dimension. So they really have a two-dimensional palette, whereas we have this third dimension where red and green are opposites. So now we have a two-dimensional palette, whereas we have this third dimension where red and green are opposites. So now we have a full three-dimensional palette of colors that we have. So for, and the question is why do we primates have this extra dimension? Well, for a hundred years they thought that it had something to do with finding fruit

in the forest, something about eating. The problem with that hypothesis was that the primates that have color vision have the same color vision with the same exact kind of peculiar kind of red-green vision, which I'll talk about in just a second. But the kinds of diets that they have is radically diverse. Even within one species, you know, it'll be a tremendously varied kind of diet of fruits and vegetables and sometimes meats. And yet they have this very conserved kind of peculiar kind of red-green vision. But what I was able to show was that, in fact, one of the most important things for our color vision is not fruit or leaves or anything like that. It's about other people. And it's seeing the emotions on the bare skin of other

people, seeing their blushes and their blanches and their flushes. And all of these color modulations that happen on bare skin give you a truthful view into the psyche or the current state of another person on their bare skin. It's seeing though, in order to see that, in order to see this at all, you actually have to be sensitive to the blood under the skin. That's what allows you to see these color signals. have to be sensitive to the blood under the skin. That's what allows you to see these color signals. But to be sensitive to the blood, it turns out, for uninteresting reasons about the nature of hemoglobin as it gets oxygenated and deoxygenated, it turns out you have to have sensitivities in the spectrum right next to each other in this particular spot, because otherwise you couldn't sense it getting oxygenated and deoxygenated. So the weird peculiarity that we have for our

red-green vision is exactly what it has to be in order to sense the blood changes that are going on under the skin, which is what allows us to see all these emotional states as well as health states under the skin. So it helps us read other people. That's right. It's an empath. It really is about reading other people. And I think it's probably a mix of emotions and health. If you've ever had an infant, not only are you gauging their emotion, but you're also gauging their health. Are they breathing? Like if it's a suckling baby, it's nearly, you know, if you're not careful, it could also not breathe well because its nose is being pressed up against the body. So you have to be constantly sensing the state of health and emotion and just the general state of other people.

And I think it's used for a combination of all of those. It seems, though, that there are colors that we see with our color vision that we can detect that don't have anything to do with that, though, right? Yes and no. So surprisingly, there's two dimensions that we've already talked about outside of white and black, you know, grayscale. There's blue-yellow. And it turns out blue-yellow happens on your skin. If you squeeze your palm, if you squeeze your fist, then you'll seeuish or, you know, those are the parts where it's also oxygenated. So it's bluish and reddish, but it's going to get blue, yellow differences are due to concentration differences of the blood under your skin. So your skin can already vary along a blue, yellow dimension, but the other dimension of hue is red, green, and you get red, green differences, not by virtue of how much blood is under the skin, but by how oxygenated it is. More oxygenated is redder, less oxygenated, like where your veins are, are greener. So the other dimension of your color space is red-green, and that also can happen on skin. And so your skin,

between being more oxygenated or less oxygenated, red-green, or being more blood under the skin and less blood under the skin, which is blue-yellow, you can achieve any hue at all, actually, on human skin. So surprisingly, all of the hues of the rainbow, you know, from blue to green, yellow, orange, red, and then purple, which is not part of the rainbow but connects over to violet, all of those hues, in fact, can happen on human skin. We're much more like chameleons and much more color changing than most of us ever appreciate because although we're innately amazingly good at reading these signals, it's all implicit. It's all unconscious. You're not consciously aware of it. So let's talk about something that I think everybody wonders about from a very early age,

from the time you first go swimming and you come out of the lake or the pool or wherever you've been swimming and your fingers are all pruney and wrinkly and when you think about it most things when they get wet plump up the water makes them plump up and yet your fingers do the opposite and they get smaller and wrinkly so what's going on on? Yeah. So on it, this is one of these Wikipedia level wisdom that never seems to go away and doesn't even make sense on its face because when things, again, like, like you said, when things get wet, they typically balloon up and actually get less wrinkly. So a student of mine and I, and I had been working on something else and I had encountered something hand-related

that led me to a paper from the 1930s. And so doctors have long noticed for nearly 100 years that if a patient comes in and they have nerve damage, they've been in a car accident, say, and they have nerve damage in their arm or they might have nerve damage and the doctor isn't sure, is there a nerve cut? Because the patient's still unconscious and you can't ask the patient,

can you move your fingers? So they want to check, and so they realize that if you stick the patient's fingers in warm water and they do wrinkle, then they don't have a nerve cut. And if they don't wrinkle, then there's a sympathetic nerve cut. And so they'd already realized this was a potential diagnostic tool. But already then what it implies, and what still Wikipedia didn't know, so to speak, is that it's not just a process of local osmosis and absorption of water. It requires an active neural connection to the brain.

And that then suggests that, well, maybe this is not just some weird, stupid side effect, but something maybe on purpose that evolution has sort of decided to do for some reason. And so the question was what? And I had a student at the time named Roman Weber, and I just said, what could be the good reason to get wrinkly fingers when it's wet? And then he just sort of off the cuff said, well, could they be rain treads? And then we worked out mathematically, what would the optimal rain treads have to be on this kind of shape finger. You can work out the shape and how people grip. What would, in fact, the optimal channels have to be to channel out water upon a quick grip so that they channel out without hydroplaning.

You don't want the water to get stuck between you and your finger and the surface. You want it to drain out super quickly so that you don't hydroplane. And you can work that out mathematically. And so those treads, those wrinkles that we get on our fingers when they're wet, they are actually the perfect tread to help us grip things when our hands are wet,

which I guess, I mean, that's evolution, right? That's right. I mean, this is a really smart case. This is smarter than anything that humans have ever engineered. Our car treads have permanent treads in them. But in fact, on dry days, you don't want treads in them. Race cars, which are racing during dry conditions, have smooth tires.

And you might, some people think this is counterintuitive at first. It's just like, well, that's got to be really bad grip. No, that's perfect grip in dry conditions. Why? Because you want the most amount of your tire to be really bad grip. No, that's perfect grip in dry conditions. Why? Because you want the most amount of your tire to be touching the ground because more tire touching the ground is more grip. The only reason you want treads in there is because when it's raining, you need to be able to channel that water out so that you don't just slide on this thin film of water. We have, you

have to actually change your tires in this case, you know, or put, you know, regular shoes versus rain tread shoes on. Whereas our case, we actually have rain treads, which come out only when they're needed. Once the body recognizes it's been wet for a while, it says, oh, it may be it's rainy or dewy. Let's go ahead and put our rain treads on. Do our feet do it too? Toes do it? They do. Yeah. It takes a little bit longer, but there's plenty of photos you can find of others, and if you spend enough time in the tub, you'll see your toes wrinkle as well. Yeah, and next I want to ask you about why our eyes are where they are. Mark Changhisi is my guest. He is a cognitive scientist.

He has a YouTube series about all things science-related, and he's author of the book, The Vision Revolution, How the Latest Research Overturns Everything We Thought We Knew About Human Vision. Contained herein are the heresies of Rudolf Puntwine, erstwhile monk turned traveling medical investigator. Join me as I study the secrets of the divine plagues and uncover the blasphemous truth that ours is not a loving God and we are not its favored children.

The Heresies of Randolph Bantwine, wherever podcasts are available. People who listen to Something You Should Know are curious about the world, looking to hear new ideas and perspectives. So I want to tell you about a podcast that is full of new ideas and perspectives, and one I've started listening to called Intelligence Squared. It's the podcast where great minds meet.

Listen in for some great talks on science, tech, politics, creativity, wellness, and a lot more. A couple of recent examples, Mustafa Suleiman, the CEO of Microsoft AI, discussing the future of technology. That's pretty cool. And writer, podcaster, and filmmaker, John Ronson, discussing the rise of conspiracies and culture wars. Intelligence Squared is the kind of podcast that gets you thinking a little more openly about the important conversations going on today. Being curious, you're probably just the type of person Intelligence Squared is meant for. Check out Intelligence Squared wherever you get your podcasts. So, Mark, humans have eyes in the front of their

head as do a lot of animals but a lot of animals don't fish horses they have eyes on the sides of their head so why why do why do our eyes face forward so the question about why we have forward facing eyes compared to other animals, many of which who have more sideways-facing eyes, is something that everybody often thinks they know. And if you ask anybody, they'll say, oh, well, animals have forward-facing eyes because they're predators. Now, the problem with that hypothesis is that nearly all of the predators on Earth have sideways-facing eyes.

All of the fish that you've ever met all have sideways-facing eyes, and all of those fish eat other fish, right? That's what they do. All of the birds, you know, most of these birds that you've ever seen have incredibly sideways-facing eyes, which means they can see above and behind them and below them, in front of them. They get a full view all around them, and they're predators. Even the carnivores, which are the dogs and bears and cats and things like this, they have less forward-facing eyes than do we, and they do happen to have more forward-facing eyes than many others, and they do happen to be predators, and I think it's because those predators are the ones that are closest to our lives

that people sometimes make this correlation, but it's a false correlation. And the ones that have the most forward-facing eyes are us apes, for example, and some of us primates. And we're not particularly predatorial at all. We eat all kinds of things, the apes that have this. So forward-facing eyes isn't explained because we're predators. That's not a good explanation. So I was trying to look for, well, what could potentially explain this? And it's actually a much simpler explanation. And my hypothesis was just this, and it's just see the most in the habitat where you happen to be living. If you're an animal that's out in the prairie without any forested environment, well, to see the most, you want eyes on both sides of your head because then you can see all around you. However, if you're in the forest, things

change. Now, if you're small and in the forest where there's all of these leaves, it still turns out that you should still have eyes on the sides of your head because the separation between your eyes is so small that you get no advantage at seeing around leaves. Now, what do I mean by seeing around leaves? If you've ever held up your finger in front of your eyes, in fact, just do this right now, pull your finger up in front of your eyes and look beyond your finger, well, you'll see two copies of your finger, unless you have a dominant eye. You'll see two copies of your finger, and each one will be rendered as semi-transparent. So you see two fingers, one for each eye, and you see one world beyond it.

But I want you to notice that if you close one eye, part of the world is being blocked. But when you open up both eyes, you still see that part of the world that was being blocked with the other eye, and you're seeing it through the semi-transparent finger. If you open up all of your fingers vertically in front of your eyes, you'll still see nearly 100% of the world beyond your fingers. Again, fixate beyond

your fingers. And that's because each eye is able to stitch together what's missing from the other eye, and they stitch it into a single unified perception of the world beyond. These particular mechanisms we evolved to stitch together views that one eye gets beyond a layer of clutter and what the other eye gets beyond a layer of leafy clutter and stitch them together to make one unified perception. Now, once an animal has this kind of capability, you actually can see more in the forest if your eyes are facing forward. But this only works when your eyes are more widely separated than the typical leaf. Again, if you're a mouse in the forest, your eyes are so

close together, this kind of trick doesn't work. It would be like holding a beach ball in front of your eyes and trying to play this game that I just said. It's a beach ball. You can't see around your beach ball or through your beach ball. So it turns out that the animals that have forward-facing eyes and are the large ones that are in forested leafy habitats. They're the ones with forward-facing eyes. Otherwise, the smaller they get within force, the less forward-facing their eyes, and animals outside of force just have sideways-facing eyes. One simple hypothesis explains all of the variation in whether your eyes face forward or sideways, and it's just see the most in the environment that you happen to be in.

And so if we were potentially in a different environment, we would, our eyes might be somewhere else, like a fish's eyes. I mean, I imagine the same applies to them, right? Well, that's right. So even ourselves right now, we are designed for leafy environments, our forward-facing eyes. We rarely today are in leafy environments. Our eyes now are in a situation where we're nearly never around leafy objects that we can see around. We're, you know, with cars and just sort of big objects around us. So they're, in fact, not optimized for our environment today. However, if we were to be back in the forest, and this is how, in fact,

I came to realize this. I used to play some of these sniper games, Call of Duty, when I was younger, and I would be playing a sniper, and I'd be sitting in these fake bushes on these online games. And you can't see out of a bush very well when you're playing those games, because you're, in fact, a cyclops in those games. You're only getting one view from the screen. Sure, I have two eyes when I'm playing the game, but I'm only having one screen view given to me. So if I want to see out of the bush so that I could shoot the enemy, I have to keep wiggling left and right to see out of these little holes. But when you're in a real bush in real life with two eyes that we have that are bigger than most of the leaves that are in there, you can see really well out of that bush. So you have this x-ray vision, I call this,

sort of this x-ray vision capability that we have by virtually having two forward-facing eyes that are widely separated, gives us the ability to see up to six times better the world in front of you, even though we lose the ability to see behind us like bunny rabbits can see behind them and so forth. We lose that, but within forested environments, we can see up to six times better up front, which offsets the loss of being able to see behind us. So this is not a particularly human question, but the question is, why is my brain inside my head as opposed to somewhere else? But that's true for a lot of animals, and I imagine the explanation is the same for most. But when you think about it, the head is a pretty fragile place to put it, but nevertheless, there it is. And at first glance, it's a really

bad place to put a brain. It's even a worse idea when you look at most animals, because most animals walk with their head leading. So why would you place it in the head? And the answer is that one of the most difficult things about building a nervous system is the amount of wire that it takes to build it. And so when a nervous system is evolving, it has to figure out clever ways to make sure that it's not using too much wire. Now, the question about why the brain is in the head comes down to trying to save wire. So the reason the brain is in the head is not because it's a good place to put the brain for safety, but because the thing that's also up in the head is all of your perceptual apparatus. You see with your head, you hear with your head, all of the places that you want to put sensors are going to be in the leading part of the vehicle, right? That's where all the

sensors are. And once the sensors are there, well, if you want to minimize the amount of wiring that you have to use, then the best place to put the brain is right up against those sensors. Otherwise, if you pull the brain, let's out, you know, into your rib cage, all of those trillions of, of, uh, uh, sensories endings there have to have then independent wires that extend all the way to the rib cage, which would be a massive amount of weights and volume that you then your body would have to support and then have to support more musculature to support that. It becomes an entirely, you'd end up having to have a brain, the size of a bathtub or something in order to make all of that happen in terms of the entire size of your nervous system.

So by having the brain in the head, it's not per se because it's safe. It's there because it's the optimal place to minimize the amount of wire. I always enjoy these conversations about things that you've either wondered about or when you hear them, even if you haven't wondered about them, you think, yeah, why is that? Why is my brain in my head? And now we have some answers. Mark Changhisi has been my guest. He is a cognitive scientist. He has a series on science on YouTube,

and there's a link to his YouTube channel in the show notes. And Mark is also the author of the book, The Vision Revolution, How the Latest Research Overturns Everything We Thought We Knew About Human Vision. And there is a link to that as well in the show notes. Thank you, Mark. Thanks for being here. Thanks so much, Mike.

It's been a pleasure. Hey, everyone. Join me, Megan Rinks. And me, Melissa Demonts, for Don't Blame Me, But Am I Wrong? Each week, we deliver four fun-filled shows. In Don't Blame Me, we tackle our listeners' dilemmas with hilariously honest advice.

Then we have But Am I Wrong? which is for the listeners that didn't take our advice. Plus, we share our hot takes on current events. Then tune in to see you next Tuesday for our Lister poll results from But Am I Wrong? And finally, wrap up your week with Fisting Friday, where we catch up and talk all things pop culture. Listen to Don't Blame Me,

But Am I Wrong on Apple Podcasts, Spotify, or wherever you get your podcasts. New episodes every Monday, Tuesday, Thursday, and Friday. Do you love Disney? Then you are going to love our hit podcast, Disney Countdown. I'm Megan, the Magical Millennial. And I'm the Dapper Danielle. On every episode of our fun and family-friendly show, we count down our top 10 lists of all things Disney. There is nothing we don't cover. We are famous for rabbit holes, Disney themed games, and fun facts you didn't know you needed, but you definitely need in your life. So if you're looking for a healthy dose of Disney magic, check out Disney Countdown wherever you get your podcasts.

Do you use online reviews when you make a purchasing decision? Those reviews can be an important factor in making sure you make a smart purchase. And there are plenty of other factors as well. How you evaluate those product reviews and those other factors can make a big difference in how satisfied you are with your purchase. Bart DeLange is a behavioral scientist and a marketing professor at a business school in Barcelona, Spain, and he is an expert in the subject of how we decide what to buy and how product reviews can be helpful, and sometimes not so helpful.

He has a very interesting TED Talk on the subject, and there is a link to that TED Talk in the show notes here. Hey, Bart, welcome to Something You Should Know. Thank you. Thanks for having me. Sure. So I suppose this is an overly simplified question to what is probably a much more complex answer, but why do people buy what they buy? I don't think there's a simple answer.

Human beings are complex, and there's many reasons why we buy or don't buy. On the one hand, there's the benefits of the products that we're considering. On the other hand, there's also the structure of the environment that we take into account when we make decisions. So for instance, when there's many other consumers buying a certain product, that makes the product more attractive to us and we'll be more likely to buy that product. In addition to the objective features of a product, we also rely on marketing variables such as the price of a product and advertising and branding and so on. So it's a complex story. Is it safe to say that we're fairly easily swayed by these things that either marketing

or, like you said, you know, if lots of people are buying it, it's like when you go out to eat, you don't want to wait in line. But if you see a restaurant that has no wait, you go, well, I don't want to go there. There's nobody there. So it's all these kind of strange little influences, but they sway us quite a bit. That's right. It is very difficult for consumers to evaluate the objective, intrinsic quality of products and services. So you go to a restaurant and you can form an evaluation of a prediction of how much you might like the food in that restaurant by looking at the ingredients and so on. That is a very difficult thing to do. So we look for clues in our environment that simplify that prediction process.

And so what other consumers are doing, the recommendations that other people are giving, the prices that the restaurant is charging, all of those extrinsic cues have a major influence on what we end up doing. Isn't so much of the answer to, did I make the right purchase here, isn't a big part of it just how satisfied you are? In other words, it isn't always an objective, did you buy the right car? It's more, did you buy the right car for you? Because the right car for you might be a horrible car for me. So you may have made the right purchase, but if I bought the same thing, it would have been the wrong purchase, right?

I think that makes sense for some products. You know, you could say the goal in life is to maximize happiness or satisfaction, and as long as I feel happy, I'm doing the right thing. On the other hand, you could feel happy and satisfied about the purchases you made, but at the same time, spend a lot of money that you shouldn't be spending, paying way too much for the products and services that you acquire. So that's one thing to consider. The other thing is, you can be really satisfied, but buy products that are objectively poor. So for instance, think about you want to buy a bike helmet. What you care about is

the safety of that bike helmet in case you have a crash. You want the bike helmet to protect you. You buy batteries. You want these batteries to last a long time. There's many products that you buy for an objective benefit, and you can be satisfied with your purchases, but at the same time, pay a lot of money for suboptimal performance. And I think that is a concern, even for those of us who are happy with our purchases. So that leads right into the whole idea of consumer reviews, online reviews, because just as you don't know how safe this helmet is or how long these batteries last, they probably don't know either. That's right, yeah. It is very difficult to evaluate the quality of products.

Even if you try really hard, it is difficult to do so because you may not have the ability, you may not have all the information to evaluate those products. An additional problem with online reviews is that I think many users who leave reviews, their goals are not necessarily to evaluate the objective performance of products, but their goals may be different just to leave their opinion or to have an influence on other people or to satisfy a provider or to achieve a certain incentive and so on. And I've thought about this too, that I'm certainly more likely to be motivated to leave a review if I don't like it than I am if I do. That, you know, to complain is kind of human nature.

Yeah. So there's a major problem with online reviews is that we only observe the ratings from a self-selected sample of users. There's two very strong selection biases that are at play. The first one is a purchasing bias. It's those consumers who like the product enough in the first place that will leave a review. So that's the purchasing bias, and this leads to a lot of five-star ratings. And then there's a second bias, which is the brag and moan bias, conditional on purchasing a product. It's those consumers that are really happy with their purchase, or those consumers that are really dissatisfied with their purchase,

that are most likely to leave a review. And the end result is these J-shaped distributions, these bimodal distributions that you see for almost any product in all product categories, where you have a very large number of five-star reviews, and then a little bit less four-stars, almost no three-star, no two-stars, and then another bump at one star reviews. And so this suggests that there is a very strong selection mechanism going on. You're basically not observing the evaluations of consumers who feel moderately, moderately satisfied about their purchase. Yeah, well, who's going to take the time to write a review that says,

well, it was okay. It was fine. It was just okay. I mean, you're right. It's usually real big fans of a product or service or whatever, or people who really don't like it at all, because there's not a whole lot of motivation if you're just sort of in the middle somewhere. That's right. And yet I do think there is potentially information to be extracted there. So there is a difference between a consumer who gives a three-star versus two-star versus a four-star. And so the more ratings you have for a product and the less selective those ratings are, so the more representative the sample of consumers are from which you observe ratings, the better and the more informative the average user rating is going to be about the actual performance of the product.

And so knowing what you know, do you use consumer ratings? Do you use online reviews? Or do you just say, no, there's got to be a better way? Well, the answer is complex. So I used to rely more on reviews in the past than I do now after studying online reviews for years. So I rely on them less. I do still rely on them to some extent. It's just really, really difficult to ignore. You know, you go to Amazon and you see a product that gets a 4.5 star rating and another one that has a 3.5 star rating. I know that that one star difference may not

actually be informative, but it's really difficult for me to inhibit that tendency to rely on those ratings. So I do it, I rely on them less, but I do still rely on them. Another reason why I still rely on them is because I'm a human being in a social system. And if the consumers that make decisions together with me, like my spouse and my kids and so on, want to rely on reviews. Like I can't, it's difficult for me to be the nerd and say, hey, I've studied thousands of products across more than, you know, hundreds of product categories. And I know that user reviews are not diagnostic.

They'll say, dad, husband, shut up. We're going to go to the restaurant that gets the highest ratings. Another reason I think to rely on reviews is that other users could mention certain specific features or benefits of products that you may not have been aware about yet, you know, through the information that you acquire about products on the company's websites or through advertisements and so on. So I do think those references that other users are making to specific features or benefits of the products in their narrative reviews

could actually be useful. Well, it does seem that if you look at the reviews of a product and they're overwhelmingly negative, isn't that telling you something? Yeah. If you observe many, many consumers rating a product negatively, there's information in that. If you observe, on the other hand, many, many consumers rating a product or service positively, there is less information in that. So I've heard the advice that what you should do is throw out the ones at the bottom and ones at the top and look at the ones in the middle, and that is where you'll find some potentially useful information. Is that a good strategy? It could be. I don't have strong empirical evidence to support that.

So, I mean, another thing I've heard is that many people say, I only look at the one-star reviews and I look at what they have to say. And if there is anything in there that's relevant for me, then that will influence my purchase decision. So I've heard many different strategies that people use. I think, unfortunately, that most of these strategies feel satisfying to the person who's following that strategy, but actually those strategies don't get you much closer to the truth. I think what we need to make good use of all the information that is out there in online reviews are, you know, we need to rely on algorithms that sift through those reviews, all that textual information in an objective, even-handed way, and extract information that is in those reviews. Our human minds are not in a good position to do that. We

are easily swayed by emotions and stories and things that make sense to us, but are objectively perhaps not so meaningful. You know, I've always wondered if you buy something and you buy it because you saw all these five-star reviews, are you more likely to be satisfied with it because you want to be one of, you know, you want to agree with everybody else? Whereas if you bought it and you didn't see all those five-star reviews, would you evaluate it more critically and maybe not like it as much? Yeah, I think that might be true. Again, I'm not aware of any study that has systematically examined this, but this general phenomenon is something psychologists call motivated reasoning

or confirmation bias. If you pay a lot of money for a new product, then you make yourself believe that this is a good product. If you pay a lot of money to go to a fancy restaurant, you will like the food. If you buy a product that is from a well-known, trusted brand, you're much more likely to evaluate your experience positively. And I think reviews may work in a similar way. If you do something that many other people evaluate positively, you're going to interpret your experience also in a confirmatory way. Your expectations bias your interpretation of your experience. If your expectations are high, you will interpret your experience more positively. Is there any sense as to the number, somehow some sort of number, because if there's only two reviews and they're both negative,

well, you know, the reviews of this restaurant could be the restaurant across the street left negative reviews on purpose to dissuade business. I mean, is there a sense of critical mass here of how much is enough for you to really have some reliance on what they're saying? It's difficult to say, but two reviews, definitely ignore. You know, you just need to think about all the potential issues or limitations of online reviews. The idea that it is difficult to evaluate the objective quality of products for lay people. The idea that the opinions of users are not independent of each other. So the first rating a product receives online has

an influence on the next rating, and those ratings have an influence on subsequent ratings, which we call herding effects. There's fake reviews, there's incentivized reviews, and so on. There are so many different issues with each individual review that you need to collect a lot of data to overcome those issues, to get some signal from that noisy data. So if you want me to give you a number, I'd say 100 reviews. If it's below that, put very little trust in the average rating. Do you differentiate between ratings and reviews? Because it seems that it's a lot easier to just click a star or four stars or five stars than to actually sit down and write a paragraph. So maybe that's more representative? That is a possibility. So

I do use the textual information as well because I think there could be references to objective features of the product there that are informative. So, for instance, I'm tall, and if another user says, hey, I'm 6'6", and when I use this product, it makes my back hurt, it's uncomfortable, that is diagnostic information for me that I do take into account and that I otherwise wouldn't be aware of. The problem is that we can easily be persuaded by textual reviews in ways that we shouldn't be. So for instance, we take into account how confident the reviewer is, for instance, whether the reviewer uses confident language or not. But we don't know whether confident reviewers actually provide more diagnostic information about product performance or not. We may take into account whether a reviewer posts a lot of reviews on Amazon, believing that expert reviewers are in a better position to evaluate the performance of products, but

maybe they're not, and so on. So I believe that these additional pieces of information that go beyond the star rating, they could be informative, but I'm worried that us as human beings selectively attend to bits and pieces here and there. And as a consequence, our overall judgment will not be much better. What we really need is algorithms to sift through all that information, weigh it in an even-handed way, and then try to extract as much information as possible and provide a good recommendation to human beings. And then as human beings, we just need to accept that algorithms are in a better position to extract information from those textual reviews. Does anybody do that?

Yeah, the technology definitely exists. You could probably find websites here and there, review aggregators, that use some of that technology. I think you need companies like Amazon or Google or TripAdvisor or Yelp to really buy into that and start making use of that technology. What they're doing right now is something that is related to it, but I don't really think they have the welfare of consumers in mind. So, for instance, what Amazon is doing is saying like, hey, some reviews are going to be more diagnostic than others. So they recognize that. But the way they discriminate between helpful reviews and unhelpful reviews is by asking other consumers, right? So we can go to Amazon and say,

oh, I read this review and then click a button and rate this review as helpful or as unhelpful. And then those reviews will then be featured more prominently on Amazon, and they will receive a larger weight in the average that Amazon presents. Or they will weigh reviews from reviewers that write a lot of reviews more than from reviewers that write a few reviews and so on. So they use algorithms to emphasize certain reviews more than from reviewers that write a few reviews and so on. So they use algorithms to emphasize certain reviews more than other reviews. But I don't think that these algorithms are developed with the objective of maximizing the information that consumers receive about objective product performance. Instead, these algorithms are most likely, and I cannot be sure, but they're most likely developed to maximize the likelihood that consumers will buy on those

platforms. Well, there's certainly a lot to it. And I think maybe it's because I do this. I'll sometimes look at reviews and look for that review that kind of confirms what I want it to confirm, that this is a good thing for me. And if I find it, I'm much more likely, even in light of other negative reviews, if I find that one that really confirms what I'm kind of thinking, that sways me a lot. But this is really interesting. I've been speaking with Bart DeLange. He is a behavioral scientist and marketing professor in Barcelona, Spain, and he has a really interesting TED Talk on this. There is a link to that in the show notes. Thanks for being here, Bart. All right. Thank you so much.

Wrinkles are inevitable, but there are some things that you can do that will make them worse or better. A lot of wrinkling happens in the car, so if you're spending hours in your vehicle each day, UVA rays, which cause the majority of wrinkling of the skin, have ample time to penetrate your window, regardless of whether it's sunny or not. So if you're driving, you should wear sunscreen. Fruits and veggies such as raspberries, blueberries, red bell peppers, and spinach contain antioxidants, which can allow your skin to better defend against environmental damage so that it can stay supple and radiant longer. As a general rule, whatever promotes a heart-healthy diet is also beneficial to your skin. Favoring one side when you sleep could increase lines. When you sleep on the same side of your face night after night, the skin gets

repeatedly smashed up against the pillow and won't smooth out or spring back as quickly as it did when you were younger. To prevent the likelihood of those lines altogether, try getting used to sleeping on your back. Frown lines, which are creases between the eyes, may actually suggest that you're overdue for an eye exam. Some people overcompensate for eye issues by squinting, which causes those wrinkles. Drinking water can make a difference. Staying hydrated keeps your skin soft and supple. When your skin is dry, wrinkles become accentuated. And a lot of this is your parents' fault. No matter what you do, wrinkles are largely genetic.

One way to predict how your face will age is to look at the face of your mom and dad. And that is something you should know. And that brings us to the end of this episode of the podcast. I hope you'll share it with your friends and dad. And that is something you should know. And that brings us to the end of this episode of the podcast. I hope you'll share it with your friends and family. I'm Mike Kerr Brothers. Thanks for listening today to Something You Should Know. Welcome to the small town of Chinook, where faith runs deep and secrets run deeper. In this new thriller, religion and crime collide when a gruesome murder rocks the isolated Montana community. Everyone is quick to point their fingers at a drug-addicted teenager,

but local deputy Ruth Vogel isn't convinced. She suspects connections to a powerful religious group. Enter federal agent V.B. Loro, who has been investigating a local church for possible criminal activity. The pair form an unlikely partnership to catch the killer, unearthing secrets that leave Ruth torn between her duty to the law Thank you. Kelly Marie Tran and Sanaa Lathan. Listen to Chinook wherever you get your podcasts. Hi, this is Rob Benedict. And I am Richard Spate. We were both on a little show you might know called Supernatural.

It had a pretty good run, 15 seasons, 327 episodes. And though we have seen, of course, every episode many times, we figured, hey, now that we're wrapped, let's watch it all again. And we can't do that alone. So we're inviting the cast and crew that made the show along for the ride. We've got writers, producers, composers, directors, and we'll, of course, have some actors on as well, including some certain guys that played some certain pretty iconic brothers.

It was kind of a little bit of a left-field choice in the best way possible. including some certain guys that played some certain pretty iconic brothers. It was kind of a little bit of a left field choice in the best way possible. The note from Kripke was, he's great, we love him, but we're looking for like a really intelligent Duchovny type. With 15 seasons to explore, it's going to be the road trip of several lifetimes. So please join us and subscribe to Supernatural then and now.