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Consider the Hollywood actor giving the classic “follow your dreams and never give up” line is bad advice and is pure survivorship bias at work. Well what is surviorship bias? Let’s take a look friends and learn. :)
“Survivorship bias, or survival bias, is the logical error of concentrating on the people or things that “survived” some process and inadvertently overlooking those that did not because of their lack of visibility. This can lead to false conclusions in several different ways. The survivors may be actual people, as in a medical study, or could be companies or research subjects or applicants for a job, or anything that must make it past some selection process to be considered further.
Survivorship bias can lead to overly optimistic beliefs because failures are ignored, such as when companies that no longer exist are excluded from analyses of financial performance. It can also lead to the false belief that the successes in a group have some special property, rather than just coincidence (Correlation proves Causation). For example, if three of the five students with the best college grades went to the same high school, that can lead one to believe that the high school must offer an excellent education. This could be true, but the question cannot be answered without looking at the grades of all the other students from that high school, not just the ones who “survived” the top-five selection process.
Survivorship bias is a type of selection bias.”
“During World War II, the statistician Abraham Wald took survivorship bias into his calculations when considering how to minimize bomber losses to enemy fire. Researchers from the Center for Naval Analyses had conducted a study of the damage done to aircraft that had returned from missions, and had recommended that armor be added to the areas that showed the most damage. Wald noted that the study only considered the aircraft that had survived their missions—the bombers that had been shot down were not present for the damage assessment. The holes in the returning aircraft, then, represented areas where a bomber could take damage and still return home safely. Wald proposed that the Navy instead reinforce the areas where the returning aircraft were unscathed, since those were the areas that, if hit, would cause the plane to be lost.”
So, they said: the red dots are where bombers are most likely to be hit, so put some more armor on those parts to make the bombers more resilient. That looked like a logical conclusion, until Abraham Wald – a mathematician – started asking questions:
– how did you obtain that data?
– well, we looked at every bomber returning from a raid, marked the damages on the airframe on a sheet and collected the sheets from all allied air bases over months. What you see is the result of hundreds of those sheets.
– and your conclusion?
– well, the red dots are where the bombers were hit. So let’s enforce those parts because they are most exposed to enemy fire.
– no. the red dots are where a bomber can take a hit and return. The bombers that took a hit to the ailerons, the engines or the cockpit never made it home. That’s why they are absent in your data. The blank spots are exactly where you have to enforce the airframe, so those bombers can return.
This is survivorship bias. You only see a subset of the outcomes. The ones that made it far enough to be visible. Look out for absence of data. Sometimes they tell a story of their own.
BTW: You can see the result of this research today. This is the exact reason the A-10 has the pilot sitting in a titanium armor bathtub and has it’s engines placed high and shielded.
If you want to think scientifically, ALWAYS ask what data was included in a conclusion. And ALWAYS ask what data was EXCLUDED when making a conclusion.
How many people are well-read enough to see what is happening? The assault on journalism and journalistic values in the name of bloody acquiescence to power grinds onward. A excerpt from Robert Fisk’s article “We Do Not Live in a “Post Truth” World, We Live in a World of Lies and We Always Have.”
“Today, you can not only deny history – the Armenian and Jewish Holocausts, Anne Frank’s diary, the gas chambers of Auschwitz – you can also tell fibs, big or small, about almost anything which annoys you. The Middle East, with our journalistic help, is deep in the same false world. Every dictator is now fighting “terrorism” – along with the US, Nato, the EU, Russia, Hezbollah, Iran, the entire Arab Gulf (minus Yemen, for rather embarrassing reasons), China, Japan, Australia and – who knows? – Greenland as well.
But justice is not on the menu. This is a word which few politicians, statesmen, even journalists, any longer use. Neither Trump nor Clinton, nor the Brexiteers, have talked about justice. I’m not talking about justice for victims of “terror”, or Brits who think they’ve been cheated by the EU, but real justice for entire nations, for peoples, for the Middle East, even – dare I mention them? – for Palestinians. They do not live in a “post-truth” world. They’ve been living among other people’s lies for decades.
The only effect of last year’s political earthquakes is that we shall feel less guilty in repeating all these lies. They have now – like war – become normal, a “diversity of perspectives”, part of a familiar, fraudulent world in which untruthfulness has acquired a “weird authenticity”.
Trump is Hitler. Trump is Jesus. National suicide is reincarnation. We may not yet have understood this. But there are many in the Middle East who will understand us. Maybe they’ll have the last laugh.”
Check your sources, use some of your time to evaluate the merit of an argument being made in the media, as a citizen it is your duty to inform yourself to the best of your ability as to how the world works and how to change it toward the better.
Not owning a television is one of the best decisions TIO and I made. Well, we do have a TV but no cable so we can watch the occasional DVD if we so desire. What the media focuses on and what is important is often two very different sets of ideas. There are multiple cases of human suffering and abuse going on in the world at any given time; but often we are inundated with the very important happenings of celebrities and the random piffle they do as a substitute for what is actually happening in the world. As pointed out by Christian Christensen in his opinion piece on Al Jazeera “More Guantanamo and Global Warming and Less Knox and Justin Bieber.”
Amanda Knox has, with her second “guilty” verdict for the murder of Meredith Kercher, re-entered our media landscape. There is nothing inherently wrong with some coverage of the Knox case, but the level of exposure afforded the story since it first broke in late 2007/early 2008 has undoubtedly been magnified by a heady mixture of sex, drugs, violence and a lead character with an image and nickname many editors seem unable to resist. The murder of Kercher is tragic, and it appears that the Knox conviction is highly suspect. Yet, as with Miley Cyrus and Justin Bieber, the volume of coverage afforded vacuous, salacious and/or sexed-up stories should lead us to consider what would happen – at the very least politically – if equivalent levels of journalistic time and energy were devoted to other issues.
Consider where Christensen thinks we ought to be spending our time rather than the current (ongoing)Bieber/Cyrus/Knox dramas.
Iraq: Since 2008, over 37,000 civilians have been killed in Iraq. That’s just over twelve 9/11 attacks, or the equivalent of 370,000 civilians dying in the US (Iraq’s population is 10 times smaller of that of the US). In other words, like wiping out a city the size of Tampa, Florida. Since the bulk of the US media were more than willing to cheerlead a war based on a blatant falsehood, a recalibration of the coverage of the aftermath of this debacle is perhaps in order.
Global warming/climate change: The US remains the home of more political climate change sceptics than any other country in the so-called “developed world”. Despite the near-unanimous position of scientists around the world, US politicians continue to display mind-boggling scientific ignorance (wilful or otherwise). Not surprising, in retrospect, from a country where 50 percent of Republicans believe that humans have existed in their present form since the dawn of time (which would be about 7,000 years ago), and politicians claim with seriousness that women’s bodies are able to miraculously prevent pregnancy in cases of rape.
Death Penalty: Between January 1, 2008 and February 2, 2014, there have been 266 executions in the US. In 2012, China, Iran, Iraq, Saudi Arabia and the US were the top 5 global executioners. Disturbingly, earlier studies have shown that US prosecutors were twice as likely to request the death penalty for a black defendant who is charged with killing a non-black victim versus a black victim; and, white defendants were twice as likely as non-white to be offered a plea agreement to reduce their sentence from execution to life imprisonment. The death penalty gets coverage, but far too many of the “What-did-he-have-for-his-last-meal?” variety.
Sexual assault: At an average of 240,000 per year, according to a study by the US Department of Justice, there have been 1.5 million rapes and sexual assaults in the US since the start of 2008. Those are big numbers. However, this study has been challenged by a study administered by the US Centers for Disease Control and Prevention in which it is suggested that the correct number of rapes and attempted rapes alone may be an astounding 1.27 million over 2013. If this is taken as an average per year, then that would be 7 million rapes since 2008. If the vast majority of victims of these assaults were men and not women, would we perhaps see more coverage? That’s a rhetorical question.
Guantanamo: Many inmates, in violation of the US Constitution, remain incarcerated without charge, denied of their basic right of habeas corpus. A lengthy hunger-strike in 2013 to protest this legal limbo was afforded a low level of media coverage. Guantanamo is a national and legal disgrace.
Everyday gun deaths: Since the start of 2008 there have been just short of 200,000 gun-related deaths in the US. While tragic mass shootings such as Columbine and Sandy Hook generate the headlines, the fact remains that gun-related deaths in general, and homicides using firearms in particular, have become a banal part of everyday life in the US. To get some sense of the relentless and often invisible flow of gun violence in the US, follow @GunDeaths on Twitter. It’s sobering.
Chelsea Manning: The person who provided the material for thousands of newspaper articles was arrested in 2010, placed in solitary confinement and subsequently sentenced to 35 years in prison. Coverage of Manning before and during her trial by the US news media was abysmal: a particularly damning indictment of journalism given the importance of the case for the future of whistle-blowing and, hence, freedom of the press.
Military spending: In 2011, of the 14 leading countries in the world when it came to spending on national defence, the US was, of course, first with an offensive $711bn budget. Even more offensive? The fact that the 13 countries underneath the US spent $695bn on national defence…combined. And, this US budget does not include the estimated $6tn (that’s $6,000,000,000,000) the wars in Afghanistan and Iraq will likely wind up costing the US taxpayers. And Manning is the one who gets 35 years in prison.
Watch the news. How much do you see of the later versus the former. Consider that without some serious media triangulation what you are ingesting is the equivalent of the Roman bread and circuses put on to keep the population stupid, obedient and passive.
I would recommend adding this to your reading lists, I’m only a third of the way though, but it has been a detailed and interesting account of genesis and growth of the large mean streak of anti-intellectualism that is currently dominating the zeitgeist of American society. Jacoby was interviewed by Bill Moyers and thus, allow me to wet your whistle with an excerpt from the transcript.
SUSAN JACOBY: Now, this was not always the case in our country. In the 19th century Robert Ingersoll, whom we’ve talked, who is known as the great agnostic, had audiences full of people who didn’t agree with him. But they wanted to hear what he had to say. And they wanted to see whether the devil really has horns. And now what we have is a situation in which people go to hear people they already agree with. What’s going on is not so much education as reinforcement of the opinions you already have.
BILL MOYERS: Yeah, why is it we’re so unwilling to give, as you say, a hearing to contradictory viewpoints? Or to imagine that we might learn something from someone who disagrees with us?
SUSAN JACOBY: Well, I think part of it is part of a larger thing that is making our culture dumber. We have, really, over the past 40 years, gotten shorter and shorter and shorter attention spans. One of the most important studies I’ve found, and I’ve put in this chapter, they call it Infantainment– on this book. It’s by the Kaiser Family Foundation. And they’ve found that children under six spend two hours a day watching television and video on average. But only 39 minutes a day being read to by their parents.
Well, you don’t need a scientific study to know that if you’re not read to by your parents, if most of your entertainment when you’re in those very formative years is looking at a screen, you value what you do. And I don’t see how people can learn to concentrate and read if they watch television when they’re very young as opposed to having their parents read to them. The fact is when you’re watching television, whether it’s an infant or you or I, or staring glazedly at a video screen, you’re not doing something else.
BILL MOYERS: What does it say to you, Susan, that half of American adults believe in ghosts? Now I take these from your book. One-third believe in astrology. Three quarters believe in angels. And four-fifths believe in miracles.
SUSAN JACOBY: I think even more important than the fact that large numbers of Americans believe in ghosts or angels, that is part of some religious beliefs. Is the flip side is of this is that over half of Americans don’t believe in evolution. And these things go together. Because what they do is they place science on a par almost with folk beliefs.
And I think– if I may inveigh against myself, ourselves, I think the American media in particular has a lot to do with it. Because one of the things that really has gotten dumber about our culture the media constantly talks about truth as if it– if it were always equidistant from two points. In other words, sometimes the truth is one-sided.
I mentioned this in THE AGE OF AMERICAN UNREASON that after the 9/11 terrorist attacks there was a huge cover story in TIME Magazine in 2002 about the rapture and end of the world scenarios. There wasn’t a singular secular person quoted in it. They discussed the rapture scenario from the book of Revelation as though it was a perfectly reasonable thing for people to believe. On the one hand, these people don’t believe it. On the other it’s exactly like saying– you know, “Two plus– two plus two, so-and-so says, ‘two plus two equals five.’ But, of course, mathematicians say that it really equals four.” The mathematicians are right. The people who say that two plus two equals five are wrong. The media blurs that constantly.
BILL MOYERS: You call that a kind of dumb objectivity.
SUSAN JACOBY: Yes. Dumb objectivity. Exactly.
As an educator I find Jacoby’s work illuminating and depressing at the same time. We have such a large hill to climb in the struggle to reclaim children’s minds from the media.
Usually by screwing up in a spectacular fashion. Search your memories (Luke) and I bet you can find a lesson painfully learned, but painfully learned well in your past.
Fast forward to school and the increasing focus on tests and testing. Everyone wants to do well on the tests, but how does photocopying facts improve your critical thinking? It doesn’t. Lawrence Davidson in Scientific American comments on the lack of critical thinking skills being taught in school:
“Informal learning environments tolerate failure better than schools. Perhaps many teachers have too little time to allow students to form and pursue their own questions and too much ground to cover in the curriculum and for standardized tests. But people must acquire this skill somewhere. Our society depends on them being able to make critical decisions, about their own medical treatment, say, or what we must do about global energy needs and demands. For that, we have a robust informal learning system that eschews grades, takes all comers, and is available even on holidays and weekends.”
So, you want people to who can think, you need to take them to environments where it is okay to ask questions and more importantly, it is okay to fail, because learning to constructively fail is one of the cornerstones of rational inquiry.
Concordance on how anecdata is no substitute for real data.