Survivorship Bias...

[5fish]

This is a problem we have in live.... I think @O' Be Joyful , @rittmeister , @jgoodguy ,@Leftyhunter , @Wehrkraftzersetzer

Survivorship Bias: The Tale of Forgotten Failures

Survivorship bias is a common logical error that distorts our understanding of the world. It happens when we assume that success tells the whole story and when we don’t adequately consider past failures.

fs.blog

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Survivorship bias is a common logical error that distorts our understanding of the world. It happens when we assume that success tells the whole story and when we don’t adequately consider past failures.

There are thousands, even tens of thousands of failures for every big success in the world. But stories of failure are not as sexy as stories of triumph, so they rarely get covered and shared. As we consume one story of success after another, we forget the base rates and overestimate the odds of real success.

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When we only pay attention to those who survive, we fail to account for base rates and end up misunderstanding how selection processes actually work. The base rate is the probability of a given result we can expect from a sample, expressed as a percentage. If you play roulette, for example, you can be expected to win one out of 38 games, or 2.63%, which is the base rate. The problem arises when we mistake the winners for the rule and not the exception. People like Gates, Lamichhane, and the Beatles are anomalies at one end of a distribution curve. While there is much to learn from them, it would be a mistake to expect the same results from doing the same things.

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Few would think to write the biography of a business person who goes bankrupt and spends their entire life in debt. Or a musician who tried again and again to get signed and was ignored by record labels. Or of someone who dreams of becoming an actor, moves to LA, and ends up returning a year later, defeated and broke. After all, who wants to hear that? We want the encouragement survivorship bias provides, and the subsequent belief in our own capabilities. The result is an inflated idea of how many people become successful.

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Survivorship bias is particularly common in the world of business. Companies which fail early on are ignored, while the rare successes are lauded for decades. Studies of market performance often exclude companies which collapse. This can distort statistics and make success seem more probable than it truly is. Just as history is written by the winners, so is much of our knowledge about business. Those who end up broke and chastened lack a real voice. They may be blamed for their failures by those who ignore the role coincidence plays in the upward trajectories of the successful

snip... WW2

However, Wald realized there was a missing, yet valuable, source of evidence: Planes that were hit that did not make it back. Planes that went down, that weren’t surviving, had much better information to provide on areas that were most important to reinforce. Wald’s approach is an example of how to overcome survivorship bias. Don’t look just at what you can see. Consider all the things that started on the same path but didn’t make it. Try to figure out their story, as there is as much, if not more, to be learned from failure.

 

[5fish]

Here a link to seven more examples...

7 Lessons on Survivorship Bias that Will Help You Make Better Decisions - I DONE THIS

Everyone loves a survivor, Right? We love watching movies like Gladiator, where a muscular Russell Crowe stands tall after defeating wave after wave of enemies. Sometimes, however, we concentrate on the fact of surviving and fixate on that and overlook everything else. This is a well-known...

blog.idonethis.com

snip... here is one...

When they plotted out the damage these planes were incurring, it was spread out, but largely concentrated around the tail, body and wings.




But Abraham Wald, a statistician at the Statistical Research Group (SRG), made a glaring observation—the military would make a terrible mistake by upgrading the armor along these sections of the plane. Why? Because the military was only looking at the damage on returned planes. They hadn’t factored in damage on planes that didn’t return.

 

[Wehrkraftzersetzer]

the bible was written that way

 

[5fish]

the bible was written that way

Interesting look at the bible...

 

[5fish]

Here are some takes...

Resolving a Talebian Paradox

There are several principles that the Nassim Taleb has talked about, including the precautionary principle, which teaches us to be cautious under cond

unearnedwisdom.com

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Survivorship bias is a useful concept only if we consider causal claims that are not necessarily true.
There was something that Taleb once wrote along the lines of, “war makes people tough”. We assume this is the case because the people that have survived the war are tough, but we don’t understand the causal chain. Does war make people tough or do tough people survive war and thus live to tell us about it?

For example, if I made a claim about religion like, “religion makes people more resilient” because when I observe religious people, I observe in them a resilient character. But are they resilient because they are religious, or are they religious because they are resilient? No way to know.

The only people that have survived, that we know about, seem to be resilient, but we don’t know about people who were not resilient and yet were religious. Here, we can invoke survivorship bias, because we are drawing an unnecessary causal link. But do we draw the same unnecessary causal link when we say that religion is useful? No, because by definition, if it has managed to give utility to so many people, it can only be considered useful.

The reason why I can question the causal direction of the previous claims (war, religion) is because neither presuppose the existence of the effect it brings. It is not necessarily true that religion makes people resilient, and not necessarily true that war makes people tough. War could make people tough or it could kill them. But it is necessarily true that for religion to have survived, it must have a functional purpose, it must be true in some way, and most likely, in a way that we cannot properly articulate

 

[diane]

This is interesting, 5fish. The generals who died early in the CW were nearly erased by the generals who either died later or survived. I've always wondered about Forrest and his five other brothers - three were reckoned to be as sharp as he was and one reckoned to be better. So...was Forrest the smarter brother? (Mycroft, I'm looking at you!) There's also the example you use of war making one tough - or successful...or legendarily successful. Joshua Chamberlain - just another bespectacled New England math teacher...like Audie Murphy was just another Texas farm boy...

This kind of harks back to the Napoleonic maxim - the formula for success was talent, opportunity and intelligence. It worked for Forrest - his brothers were missing one or the other of those three pieces. The same was true of the Union version of the Forrest brothers - the Cushing brothers. All of these people would have been farmers and lawyers and maybe teacherss without a crucible.

Is a crucible necessary for the type of survivorship bias you note? Is that what draws attention to it in the first place? That wild glow on the horizon is apt to attract far more attention than the little nail holding the house up - forever faithful vs meteor.

Is timing the key? Not so much in the context of opportunity, but era. Take two wildly successful ice cream companies who are completely different - Baskin and Robbins from the 50s; Ben and Jerry's from the 70s. (Brothers-in-law, brothers...you say potato, I say potahto!)

Have I got it sort of right? You put out such big bites!

 

[rittmeister]

This is interesting, 5fish. The generals who died early in the CW were nearly erased by the generals who either died later or survived. I've always wondered about Forrest and his five other brothers - three were reckoned to be as sharp as he was and one reckoned to be better. So...was Forrest the smarter brother? (Mycroft, I'm looking at you!) There's also the example you use of war making one tough - or successful...or legendarily successful. Joshua Chamberlain - just another bespectacled New England math teacher...like Audie Murphy was just another Texas farm boy...

This kind of harks back to the Napoleonic maxim - the formula for success was talent, opportunity and intelligence. It worked for Forrest - his brothers were missing one or the other of those three pieces. The same was true of the Union version of the Forrest brothers - the Cushing brothers. All of these people would have been farmers and lawyers and maybe teacherss without a crucible.

Is a crucible necessary for the type of survivorship bias you note? Is that what draws attention to it in the first place? That wild glow on the horizon is apt to attract far more attention than the little nail holding the house up - forever faithful vs meteor.

Is timing the key? Not so much in the context of opportunity, but era. Take two wildly successful ice cream companies who are completely different - Baskin and Robbins from the 50s; Ben and Jerry's from the 70s. (Brothers-in-law, brothers...you say potato, I say potahto!)

Have I got it sort of right? You put out such big bites!

we lost world war one because them ghastly french shot our best ww one general while he was still a fähnrich in 1871

 

[diane]

we lost world war one because them ghastly french shot our best ww one general while he was still a fähnrich in 1871

Not sure who you mean (my fault, poor on WWI!) but it does seem like more hinges on these horse-shoe nail officers than on the flashy charger general who gets memorialized by David! One Union general that has always made me wonder was Old Stars - Ormsby Mitchell. He started right off giving 'contrabands' land in SC to farm and made sure they were not molested by whites. The slaves did great - he knew they would because he had always maintained it was the foot on their neck kept them down not themselves. His success in this was impressive...then he died! Malaria or pneumonia, I think. His successors got rid of the Union villages and set up the modern equivalent of refugee camp. (These got so bad even Forrest formally complained about the condition of slaves he picked up in them.) Mitchell was also the one who cooked up the Andrews Raid - which was messed up totally by his having to move the road from under Andrews (which left him dangling quite literally...) by A S Johnston's uppity subordinates...his plan was to split the deep South from Virginia and split off East Tennessee. It would have worked but for random Confederate elements on the other side of the state! Mitchell was a real boy genius, too - that early in the war, a capture of the major railroad hub between Chattanooga and Atlanta would have basically ended the war in a year or so, not the four more it took.

 

[rittmeister]

Not sure who you mean (my fault, poor on WWI!)

well i'm thinking of a certain fähnrich who was shot off (as in shot dead) his horse in 1871 but would have been a brilliant general to win us world wor one (would all have been over at christmas 1914)

 

[Wehrkraftzersetzer]

Interesting look at the bible...

read it again, for example when they leave Babylon, historic evidence simply says maybe 10% of the Jews left Babylon* in the Bible however

* lots of clay tablets full of Jewish names long after that exodus, the fact that nearly all high ranking (and well paid) astronomers were Jews
in fact those who left were the poor and the religious


The OT is a book written by the leaders of losers

 

[5fish]

Here a link that tells about the great expulsions of Jewish people from Palestine is a myth either the Romans or Babylonians... or the exceedance for Egypt ... @Leftyhunter

https://mondediplo.com/2008/09/07israel

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But during the 1980s an earthquake shook these founding myths. The discoveries made by the “new archaeology” discredited a great exodus in the 13th century BC. Moses could not have led the Hebrews out of Egypt into the Promised Land, for the good reason that the latter was Egyptian territory at the time. And there is no trace of either a slave revolt against the pharaonic empire or of a sudden conquest of Canaan by outsiders.

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Then there is the question of the exile of 70 AD. There has been no real research into this turning point in Jewish history, the cause of the diaspora. And for a simple reason: the Romans never exiled any nation from anywhere on the eastern seaboard of the Mediterranean. Apart from enslaved prisoners, the population of Judea continued to live on their lands, even after the destruction of the second temple. Some converted to Christianity in the 4th century, while the majority embraced Islam during the 7th century Arab conquest.

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Nor is there any trace or memory of the magnificent kingdom of David and Solomon. Recent discoveries point to the existence, at the time, of two small kingdoms: Israel, the more powerful, and Judah, the future Judea. The general population of Judah did not go into 6th century BC exile: only its political and intellectual elite were forced to settle in Babylon. This decisive encounter with Persian religion gave birth to Jewish monotheism

 

[diane]

Don't forget the giants, guys! There is evidence for some very big (and healthy) people in that region, but not much about who they were or if there were enough to make a tribe. One of the last families of them were the Goliaths. (If Goliath somehow missed you his two equally big brothers wouldn't - which is why David picked up three stones for his sling.) Interesting discussions to be had about these people. The giants of today are not usually healthy, lots of difficulties, but this group was hale and hearty.

Then we can talk about the little people.

 

[Joshism]

There was something that Taleb once wrote along the lines of, “war makes people tough”. We assume this is the case because the people that have survived the war are tough, but we don’t understand the causal chain. Does war make people tough or do tough people survive war and thus live to tell us about it?

Why not both?

Success and survival are a mix of skill and luck.

Don't forget the giants, guys! There is evidence for some very big (and healthy) people in that region, but not much about who they were or if there were enough to make a tribe.

If the average person was 5'5" you could have a tribe where the average height was 6'5" and they'd be "giants" by comparison. And after a few thousand years the tale grew.

Giants are a common myth. I've come across lots of weak secondary sources referring to giant Native Americans, but good luck finding archaeology to back up outrageous claims repeated in newspapers.

 

[O' Be Joyful]

If the average person was 5'5" you could have a tribe where the average height was 6'5" and they'd be "giants" by comparison. And after a few thousand years the tale grew.

Giants are a common myth. I've come across lots of weak secondary sources referring to giant Native Americans, but good luck finding archaeology to back up outrageous claims repeated in newspapers.

I believe that Diane was joking/joshing, Josh.

 

[diane]

Why not both?

Success and survival are a mix of skill and luck.



If the average person was 5'5" you could have a tribe where the average height was 6'5" and they'd be "giants" by comparison. And after a few thousand years the tale grew.

Giants are a common myth. I've come across lots of weak secondary sources referring to giant Native Americans, but good luck finding archaeology to back up outrageous claims repeated in newspapers.

Goliath was indeed a giant, but how big that really was is debatable. During the CW, several people referred to Forrest as a giant - he was 6'2". I have reliable information that an ancestor of mine (Catawba) was over 7 feet tall. He was...formidable! It seems that Goliath and his family were all giants, healthy ones, and were working for the Philistines to basically scare the whey out of the enemy. Worked pretty well until one of the enemy wasn't so impressed!

 

[5fish]

this is for the FUBU... or soccer... or any sport...

3 common biases that plague the football world

Many flaws that affect decision-making in the financial world are also applicable to fans watching football. We look at factors like survivorship bias, sunk cost fallacy and confirmation bias, all of which exist in football.

www.sportskeeda.com

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Survivorship bias
Every year, during the transfer season, we are excited about a player our favorite football team signs. We head over to YouTube and watch videos of the goals, assists, and other skills that the player brings to a football field. After watching the video, we conclude that the player we signed is amazing. This is a classic example of survivorship bias in football.

Survivorship bias is a common logical error that occurs because we assume that success tells us the entire story of the subject. We fail to account for failures, often due to their lack of visibility. We use the success stories as an example of 'all the stories' and come to the wrong conclusions about football players.

In this case, YouTube videos are meant to show the best highlights of the player. Football highlight videos do not account for all the failures of the player. After all, who wants to watch a seven-minute video of a player losing the ball or failing to complete a pass?

For instance, here is a video of Kaka's skills and goals at Real Madrid. Kaka, of course, did not have a great time at Madrid. However, if you go by this video, you may be fooled into thinking Kaka played some of his best football at the club. Survivorship bias at its finest.

snip... another bias...

2. Sunk cost fallacy
Your favorite club just spent an absurd amount of money to sign a striker. Unfortunately for the club, the striker plays five games and has no goals to show for it. On top of this, his performances as a whole have been abysmal.

The substitute striker is clearly in better form and has scored three goals from the bench. Despite this, the star forward keeps starting games ahead of the substitute. The manager is probably falling for the sunk cost fallacy in this situation.

The sunk cost fallacy occurs when one is unable to cut losses due to the money or time spent on an activity in the past. Instead of cutting losses, more time/money is poured into that activity to attempt to make up for the initial time/money spent.

This often leads to irrational decisions as the money or time spent initially is not going to come back regardless of decisions in the future.

While the sunk cost fallacy is quite common, it is refreshing to see that Chelsea Football Club did not fall into that trap. They benched Kepa when his form was in questioned despite paying an absurd amount of money for the player.

snip... last plagues our politics...


3. Confirmation bias
A defender who you do not like has started the game for your favorite football team. In the 34th minute of the game, your team concedes a corner, and the opposition team scores. When you watch the replay of the goal, you see that the defender who you do not like was ball-watching and failed to track the player who went on to score.

Confirmation bias is the tendency to search for evidence that supports our beliefs and ignore non-supportive information. In the case of the corner, maybe the team was using zonal marking. Maybe the defender on the front post missed his header.


The reason could be something else, but if you had a preset belief about the defender, you look for evidence that supports that belief.

Being a Chelsea fan, I was not happy when Chelsea lost by two goals to Liverpool at Stamford Bridge in 2020. I am not the biggest Andreas Christensen fan and so when he brought Mane down and got a red card, I was annoyed, to say the least.

However as I had preconceived notions about Christensen, I failed to notice the mistake Kurt Zouma made that led to Sadio Mane running free. It was only until a fellow fan pointed out the mistake, did I realize I may have fallen for confirmation bias.

As Sir Arthur Conan Doyle (the author of Sherlock Holmes) wrote:

“It is a capital mistake to theorize before one has data. Insensibly, one begins to twist facts to suit theories, instead of theories to suit facts."

 

[5fish]

Here one on American Football... read the article and learn about Tom Brady...

Survivor Bias on the Gridiron - Freakonomics

The concept of survivor bias, if you don't know it, is well worth being aware of. It's most often used in finance, where it refers to a "tendency for failed companies to be excluded from performance studies" (thanks, Wikipedia). Think of the Dow Jones Industrial Average, which indexes the stock...

freakonomics.com

snip... they call it winner bias....

Winner’s bias is perhaps especially pronounced in sport. The behaviors of winners are remembered and dissected far more thoroughly than those of losers, and given greater weight, even if the outcome was decided by a tiny margin.

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This winner’s bias, if you will, shows up in pretty much every realm imaginable: academics, medicine, politics, etc. I don’t mean to sprinkle skepticism all over your inherently positive thoughts about the world, but I do think it’s worth keeping winner’s bias in mind whenever you read (or write) something about the performance of a given group or institution or coalition.

 

[5fish]

The story behind Survivor Bias...