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  • Hi, I'm John Green, and this is Crash Course: Navigating Digital Information.

  • When you were a kid, did you ever hear the phraseBecause I said so”?

  • Like, I most often say that after my kids ask why they can't have m&Ms for dinner.

  • The answer to which, of course, isyou will get scurvy if you eat that way.”

  • But that just leads to more questions about scurvy, and them begging to take a multivitamin

  • so they can eat M&Ms--It's because I said so!

  • I say this because it gets results.

  • You listen to your parents because, you know, they're your parents.

  • And also because they can take your phone away.

  • But as you grow older, “because I said sono longer cuts it.

  • If you told your boss you deserve a raisebecause I said soyou're liable to

  • get fired.

  • Also, I can't afford raises, Stan.

  • Do you think my fleet of lamborghinis pays for itself?

  • I've said it before and I'll say it again, if you want a raise, you need to learn how

  • to change the oil in a lamborghini.

  • NO!

  • You need to provide evidence that you deserve the raise, and that evidence needs to be convincing.

  • And that's how online information works, too.

  • Not only should you look for reliable sources of information, but they should provide convincing

  • evidence for their claims.

  • Solid evidence, ideally.

  • And often, they don't.

  • So today we're going to focus on how to tell good evidence from bad evidence, and

  • maybe importantly, how to identifyFine but that doesn't actually prove your point

  • evidence.

  • The stuff that the internet is built on.

  • INTRO

  • In the past few weeks, we've learned how to ask and answer the questionsWho said

  • that and why?” when we encounter new online information.

  • But those two questions alone aren't enough to properly evaluate information.

  • We need to add another question to our repertoire: “What is the evidence?”

  • Why do we need evidence?

  • Can't we just find a trustworthy source and believe whatever they say?

  • Wouldn't that just be, you know, easier?

  • Well, yes, and it's important to find and trust reliable sources of information, the

  • credibility of their claims depends on the evidence provided to back them up.

  • Evidence could be anything, really -- text, photos, videos, data -- as long as it supports

  • a claim and gives you a good reason to believe it's true.

  • If someone is making a factual claim -- and not just voicing a subjective opinion -- then

  • they need to provide proof in order for us to believe it.

  • This classic tweet by comedian Nathan Fielder explains it all.

  • In the photo you see Nathan laughing, looking off camera.

  • The tweet readsOut on the town having the time of my life with a bunch of friends.

  • They're all just out of frame, laughing too.”

  • To ruin the joke by explaining it, Nathan probably isn't out on the town with friends,

  • otherwise, he would show them laughing instead of this lonely selfie.

  • It's funny because the evidence doesn't back up the claim.

  • But often, when the evidence does not back up the claim, it's not funny.

  • It's just misinformation.

  • Or disinformation.

  • As you probably know from just existing on the internet, it is really easy to hop online

  • and make any claim you want.

  • Like, I know this is going to sound wild, but you can literally type anything you want

  • into this box and click tweet, and share it with the world.

  • Like, the only thing this box will not publish to the public is a thought longer than 280

  • characters.

  • What a system!

  • But the same is true across social media: Politicians claim their opponents are bad

  • choices for government on facebook.

  • Conspiracy theorists take to YouTube to falsely claim the Earth is flat.

  • Celebrities use Instagram to claim they lost weight using lollipops.

  • And of course, on Tumblr everyone is claiming that your fave could never, and/or is problematic.

  • If a source provides no evidence at all to back up its claims, we should be suspicious

  • immediately.

  • I mean, without evidence, we have no way to know if its claims are true -- and thus no

  • reason to believe that they are.

  • For instance, take a look at this Facebook post that went viral in the summer of 2018.

  • It was shared 1.5 million times.

  • It says, “New Deadly Spider Spreads Across USA

  • The Spider From Hell.

  • Five people have died this week due to the bite of this deadly spider.

  • This spider was first seen in South Carolina in July.

  • Since then it has caused deaths in West Virginia, Tennessee and Mississippi.

  • One bite from this spider is deadly.

  • U.S.

  • Government working on a[n] anti-venom.

  • At this time please make your family and friends aware.”

  • The source is a seemingly random Facebook user you don't know.

  • Although many posts you'll encounter on Facebook are from friends or friends of friends,

  • you'll also find posts from strangers.

  • And if they're not public figures, you may not be able to verify their identity outside

  • of Facebook.

  • So, to determine if their information is trustworthy, we need to look at the evidence.

  • The post features photos of an admittedly terrifying-looking spider.

  • But it doesn't include any other evidence.

  • It doesn't say what type of spider this is, where it typically lives, or how it traveled

  • from South Carolina to West Virginia without visiting Virginia.

  • Wait!

  • Maybe it's a flying spider.

  • Stan, are we sure that this deadly flying spider isn't real?

  • There are also, tellingly, no links to the news stories about the deaths that this spider

  • supposedly caused, because you know, there weren't any.

  • Also, there is nothing to suggest the government is studying an antidote.

  • Or for that matter, A antidote.

  • Now, fact-checking site Snopes.com debunked this all pretty easily.

  • They searched reputable sources for deaths attributed to this spider and found nothing.

  • They also found the person who initially posted this hoax has started other hoaxes in the

  • past.

  • In this case, the lack of evidence was reason to be very suspicious.

  • We didn't necessarily need Snopes to tell us there's no deadly spider taking over

  • the American south, but it is nice to be able to confirm our suspicions with another party.

  • But of course, the mere existence of evidence is not enough to verify a claim, though.

  • For instance, Oklahoma Senator James Inhofe once brought a snowball onto the Senate floor

  • in order to disprove global warming.

  • It was February 2015 and he said that scientists had claimed 2014 was the warmest year on record.

  • Then he pulled a snowball out of a plastic bag and threw it on the ground.

  • Inside the Senate.

  • He was trying to use the snowball as evidence that the planet was not getting warmer because

  • it was cold in Washington, DC -- because you know, it was winter.

  • But we know, thanks to science, that winter continues to exist in many parts of the world,

  • but at the same time, the planet as a whole is also warming.

  • A snowball does not disprove climate change any more than a heat wave proves it, because

  • weather is what happens every day in the atmosphere, and climate is what's happening overall.

  • And what's happening overall is that things are getting hotter.

  • For another example, in 2017 a conspiracy theory cropped up on anonymous Internet message

  • boards claiming the United States Department of Justice was secretly investigating a global

  • pedophile ring.

  • The so-called evidence for this included pictures of Hillary Clinton, her daughter Chelsea Clinton

  • and Sen. John McCain wearing boots for foot injuries at different times.

  • The boots were supposedly covering up ankle monitors tracking them all during the investigation.

  • But, of course, all those photos actually prove is that feet are kind of easy to injure.

  • And get easier to injure as you age.

  • All of which brings me to perhaps the most important lesson of this episode: Not all

  • evidence is created equal.

  • The evidence a source provides should come from another reliable source.

  • And if you find yourself starting to believe complicated conspiracy theories, which, by

  • the way, I think we all do on the internet in 2018, you need to ask yourself, “does

  • this information really make sense, or am I just making it make sense in my brain?”

  • And two, perhaps more importantly, 'does this information confirm my pre-existing world

  • view which makes me pre-disposed to believing it?'

  • Take this Axios report with the headlineClimate change may boost pests, stress food supplies.”

  • It says the global climate change could make millions food insecure in the future.

  • The article goes on to cite the findings of a new study from researchers at the University

  • of Washington, Stanford University, University of Vermont, and University of Colorado.

  • That study was published in Science, which some quick lateral reading can tell you, is

  • a well-respected peer reviewed journal, god I love lateral reading.

  • But they didn't just cite that one study.

  • Axios also provided context in the form of a Harvard study published in a different peer-reviewed

  • journal and comments from a scientist not involved in either study.

  • In other words, they showed their receipts.

  • So really, a search for reliable information online is a search for reliable evidence.

  • Let's take a closer look in the Thought Bubble.

  • OK.

  • Imagine this post pops into your news feed:

  • I can't believe the mainstream media is hiding this story.

  • The moon landing was fake this whole time.

  • It's accompanied by an image from the 1969 moon landing and includes a link to a video

  • called: Were the moon landings faked?

  • At face value, this post is claiming that the U.S. government never actually sent astronauts

  • to the moon in 1969.

  • The evidence provided is a video purporting to explain how they deceived the public.

  • But the presence of evidence, here in the form of a video link, does not guarantee the

  • claim's validity.

  • If you follow the link, you'll find the video in question belongs to a channel called

  • Alltime Conspiracies.”

  • It's a channel is filled with videos about conspiracy theories and supposed cover-ups,

  • like “10 real life vampires.”

  • Not exactly a trustworthy source.

  • There have only been 4 vampires in real history.

  • The video itself points out both what conspiracy theorists have said about the moon landing

  • and what official sources have said.

  • But the video is structured to make you think some questions have been left unanswered.

  • YouTube has also added an information panel to the video that points to the Encyclopedia

  • Britannica article on the Apollo Space Program.

  • Because YouTube wants you to look for information from other sources, especially around topics

  • that are prone to misinformation.

  • But let's be clear: the moon landing definitely happened.

  • And for it not to have happened, a conspiracy would have needed to involve thousands of

  • people.

  • Thousands of people never conspire to do anything secretly.

  • The video may have looked interesting, but if you check the evidence, you will see how

  • clearly wrong the post is.

  • Thanks, Thought Bubble.

  • So sometimes, the source of evidence for a claim will be reliable, it just won't exactly

  • be relevant to the argument.

  • Like, say you read a story online about how e-cigarette companies are marketing their

  • products to be attractive to teens.

  • Someone has commented on it, sayingIt's totally safe for kids.

  • After all, they help people stop smoking, don't they?”

  • But wait a minute.

  • What does smoking cessation have to do with kids using e-cigarettes?

  • Nothing.

  • This is a classic case of utilizing evidence that may be relevant to the broader topic

  • of conversation -- in this case, e-cigarettes -- but doesn't actually have any bearing

  • on the claim at hand -- that e-cigarettes are safe for kids.

  • And the use of irrelevant evidence like this can be a big obstacle when evaluating online

  • information.

  • Because not only must you determine whether a source sharing information is credible,

  • you also have to determine whether they've provided evidence and whether that evidence

  • is credible.

  • And this irrelevant evidence or evidence that doesn't quite make the right point is all

  • around us online.

  • One very popular form of irrelevant evidence is the spurious correlation.

  • A spurious correlation is the implied causal relationship between events that are coincidentally

  • linked.

  • And this happens constantly with data.

  • For instance, there's a strong correlation between the number of people who drown by

  • falling into a pool every year and the number of films that Nicolas Cage appears in that

  • year.

  • But Nicolas Cage movies do not, like, throw people into pools, because CORRELATION IS

  • NOT CAUSATION.

  • For instance, plenty of blog posts and misleading news articles have incorrectly implied a connection

  • between the rate of vaccines given to children and the rate of autism diagnoses.

  • In the past few decades, the number of vaccines recommended for kids has gone up as new medical

  • discoveries have been made.

  • The prevalence of autism spectrum disorder has also increased over the past few decades.

  • Despite bountiful scientific evidence showing there is no link between these two facts,

  • many continue to believe and use the web to spread the idea that vaccinescause

  • autism.

  • In fact, they've been so successful in spreading this spurious correlation that a drop in vaccination

  • rates and an outbreak of measles swept through Europe in 2018.

  • So this is not only about spiders that don't exist.

  • This is, in some cases, a true matter of life and death.

  • Interrogating the evidence our online sources provide us is incredibly important.

  • We need to ask whether that evidence is reliable and whether it actually backs up the claim

  • being made.

  • The quality of our evidence, like the quality of our information, effects the quality of

  • our decisions.

  • And also the prevalence of measles.

  • We'll dig even deeper into evidence next week.

  • I'll see you then.

Hi, I'm John Green, and this is Crash Course: Navigating Digital Information.

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