Wisdom of Crowds theory?

[chilidog]

Just thinking out loud here, but does the Wisdom of Crowds theory hold any water?

Basically, it's about taking the collective opinion of a group of people (preferably ones that don't have any exposure to the others, so that their opinion is their own, rather than influenced within the same group).

You could argue that the closing line itself has already taken that into consideration, in which case this wouldn't work at all.

[TommieGunshot]

For betting, especially sports betting, it is extremely important. In financials, efficient market hypothesis is more specific: https://en.wikipedia.org/wiki/Effici...ket_hypothesis

It is so important, that if it was the only thing a person used, they would win money. If it was ignored completely, it would be almost impossible to win money.

[EVPlus]

Just thinking out loud here, but does the Wisdom of Crowds theory hold any water?

Yes, but with a few caveats.

Simply following the majority won't yield a winning strategy. And, despite what some say, auto fading the public won't yield a winning strategy either.

However, this doesn't mean you shouldn't incorporate it into your modeling. If you are able to decipher when public sentiment is "wise" you'll have a powerful tool at your disposal.

Basically, it's about taking the collective opinion of a group of people (preferably ones that don't have any exposure to the others, so that their opinion is their own, rather than influenced within the same group).

In this day and age, it would be difficult for people to make decisions in a knowledge vacuum.

It's one thing to conduct an experiment in which you ask people to guess how many jelly beans are in a jar, and you prohibit them from discussing the matter with others. It's something else when information is so easily accessible.

Take stocks, for example. An equity moves up in price for any number of reasons. The momentum chasers join in and further raise the price. This, in turn, triggers indicators on trading software and more people join in. Then the average investor, bitten by FOMO, join in. Usually, this often ends poorly for the neophytes and dilettantes who eventually become trapped in weak positions if that "hot" stock drops like a brick.

I don't know if you got this idea from a blog post or a podcast (nothing wrong with that but they tend to cover any given subject on a superficial level). If you haven't already read The Wisdom of the Crowds by James Surowiecki, you might find it interesting. He takes the subject into significant depth. You may not agree with all his arguments, but it's still worth looking into.

[Bsims]

A bit off the subject, but I found fascinating many years ago while I was in an IBM management class. We were given the following exercise.

“NASA Exercise: Survival on the MoonScenario: You are a member of a space crew originally scheduled to rendezvous with a mother ship on the lighted surface of the moon. However, due to mechanical difficulties, your ship was forced to land at a spot some 200 miles from the rendezvous point. During reentry and landing, much of the equipment aboard was damaged and, since survival depends on reaching the mother ship, the most critical items available must be chosen for the 200-mile trip. Below are listed the 15 items left intact and undamaged after landing. Your task is to rank order them in terms of their importance for your crew in allowing them to reach the rendezvous point. Place the number 1 by the most important item, the number 2 by the second most important, and so on through number 15 for the least important.”

Then we randomly divided in groups of 5 and asked to repeat using a group consensus approach (wisdom of the crowd). Needless to say, I found some of the suggestions good and others not. But, we hammered out a list. Then we were given a scoring sheet and we computed our individual score and the team score. I was surprised that the team score was better than mine. The instructor then asked for a show of hands of those who had a better individual score than the team. No one in the class of 30 raised their hand. He said no one rarely does.

Here is a link to the quiz (1^st page), the correct answers (2^nd page), and the scoring method (3^rd page).

https://www.humber.ca/centreforteachingandlearning/assets/files/pdfs/MoonExercise.pdf

I learned a valuable lesson that day.

[EVPlus]

A bit off the subject, but I found fascinating many years ago while I was in an IBM management class. We were given the following exercise.

“NASA Exercise: Survival on the MoonScenario: You are a member of a space crew originally scheduled to rendezvous with a mother ship on the lighted surface of the moon. However, due to mechanical difficulties, your ship was forced to land at a spot some 200 miles from the rendezvous point. During reentry and landing, much of the equipment aboard was damaged and, since survival depends on reaching the mother ship, the most critical items available must be chosen for the 200-mile trip. Below are listed the 15 items left intact and undamaged after landing. Your task is to rank order them in terms of their importance for your crew in allowing them to reach the rendezvous point. Place the number 1 by the most important item, the number 2 by the second most important, and so on through number 15 for the least important.”

Then we randomly divided in groups of 5 and asked to repeat using a group consensus approach (wisdom of the crowd). Needless to say, I found some of the suggestions good and others not. But, we hammered out a list. Then we were given a scoring sheet and we computed our individual score and the team score. I was surprised that the team score was better than mine. The instructor then asked for a show of hands of those who had a better individual score than the team. No one in the class of 30 raised their hand. He said no one rarely does.

Here is a link to the quiz (1^st page), the correct answers (2^nd page), and the scoring method (3^rd page).

https://www.humber.ca/centreforteachingandlearning/assets/files/pdfs/MoonExercise.pdf

I learned a valuable lesson that day.

Good stuff. Thanks for sharing.

[Roger T. Bannon]

Wisdom of the Crowd basically says that a group of completely uninformed individuals will produce a better result than someone with knowledge on the subject It does not mean the crowd is right. It just means that the wisdom of collective minds tends to better than an individual and is the basis of efficient markets theory.

[StackinGreen]

Roger, you are comparing apples and oranges: it has to be a crowd of nitwits vs 1 nitwit. A crowd of nitwits isn't going to beat me guessing NFL games (let's say ML) in the long term, and it won't be close. The efficient market theory is with people who have skin in the game = they bet their own money on the outcome!

Notice how that idea keeps coming up?

[Roger T. Bannon]

Roger, you are comparing apples and oranges: it has to be a crowd of nitwits vs 1 nitwit. A crowd of nitwits isn't going to beat me guessing NFL games (let's say ML) in the long term, and it won't be close. The efficient market theory is with people who have skin in the game = they bet their own money on the outcome!

Notice how that idea keeps coming up?

Stackin, you are ignoring the fact that you lose on NFL and will continue to do so. A crowd of average NFL novices will produce a line that you cannot beat on average.

The weakness of Wisdom of the Crowd is that crowds on occasion become hysterical. This is the weakness of efficient markets theory. It is good on the average but not in the particular in rare instances.

One example of this would be the right-wing idea that coronavirus is flu which you may be familiar with.

[gojetsgomoxies]

if you took a group of high volume european bettors and spent a month teaching them american football (rules, power ratings, watching games, strategy), could they collectively come up with efficient lines for the games?

closing nfl lines being efficient i think is dependent on lots of squares and a small number of sharps...... but squares can come up with a reasonable prediction of the nfl line. later in the season, power rating lines are pretty close to the closing line...... i don't mean within a point necessarily, but usually with 3 points (and the bigger misses usually relate to injuries, which power ratings don't account for)

[Roger T. Bannon]

if you took a group of high volume european bettors and spent a month teaching them american football (rules, power ratings, watching games, strategy), could they collectively come up with efficient lines for the games?

closing nfl lines being efficient i think is dependent on lots of squares and a small number of sharps...... but squares can come up with a reasonable prediction of the nfl line. later in the season, power rating lines are pretty close to the closing line...... i don't mean within a point necessarily, but usually with 3 points (and the bigger misses usually relate to injuries, which power ratings don't account for)

Yes, think of it this way. Take women football fans that passionately watch football and take your average NFL fan. Obviously, the average NFL fan is going to think that the average women fan is clueless and they are about a lot of things with football. But their basic understanding of which team is going to win is there and if you take their collective thoughts it is going to come in line with the betting line.

The best way to think about it is the opening line. A very dedicated and very smart person has come up with these lines using sophisticated models and their own judgment. Professionals largely do not bet openers so you have basically square bettors. But square betters know a lot about their sport. They will move the line and the book will move the line, not because they think it is the right move but because money dictates it and they know from experience that those moves are usually right.

[StackinGreen]

Stackin, you are ignoring the fact that you lose on NFL and will continue to do so. A crowd of average NFL novices will produce a line that you cannot beat on average.

The weakness of Wisdom of the Crowd is that crowds on occasion become hysterical. This is the weakness of efficient markets theory. It is good on the average but not in the particular in rare instances.

One example of this would be the right-wing idea that coronavirus is flu which you may be familiar with.

You didn't treat my original argument and beyond that, you are still inaccurate. You do not understand real markets whatsoever; I gave you a chance to explain yourself and at this point, you have proven a waste of time.

[StackinGreen]

Professionals largely do not bet openers so you have basically square bettors. But square betters know a lot about their sport. They will move the line and the book will move the line, not because they think it is the right move but because money dictates it and they know from experience that those moves are usually right.

This is proof you have no idea of what you are talking about.

If you have me openers with high maximum wagers Vegas would be broke. The fact that you don't understand that's the whole reason why they limit early action shows you have zero understanding of what's going on.

[Roger T. Bannon]

You didn't treat my original argument and beyond that, you are still inaccurate. You do not understand real markets whatsoever; I gave you a chance to explain yourself and at this point, you have proven a waste of time.

No, you have no concept of what wisdom of the crowd is. The wisdom of the crowd results in a better line than you can arrive at on average regardless of whether you are sharp or not.

As for your ability to beat openers, I highly doubt you can break Vegas based on the level of analysis you have displayed. You are the very definition of a square.

[StackinGreen]

Why do they limit me then?

Lol, you have no clue about lines.

[Roger T. Bannon]

Why do they limit me then?

Lol, you have no clue about lines.

It is not hard to get limited. That doesn't mean you are sharp.

But a sharp better can beat a line because markets are not efficient. You cannot beat the line if you bet every game. The crowd is way too good for you to do that. You have to pick your spots.

The fact that a person can consistently beat the line has nothing to do with wisdom of the crowd.

[Roger T. Bannon]

The basic problem you have here is that people confuse Wisdom of the Crowd with efficient markets theory.

Wisdom of the Crowd is an observed phenomena. It is an observation.

Efficient markets theory takes the phenomena and attempts to provide a theory for why markets are hard to beat. It is based on Wisdom of the Crowd.

None of this means that the crowd is right at all times. It is just remarkably good at making observations it knows less about than an expert because it takes all things into consideration and averages them. An individual is not able to take all things into consideration.

That does not mean that you cannot have a person that is smarter than the crowd. It is just extremely hard to be smarter than the crowd more times than not.

However, efficient markets theory does say that it is not possible for any individual to be smarter than the crowd

[TheLock]

I wonder if, historically, syndicates have a bigger edge than one really great modeler. I imagine yes?

[gojetsgomoxies]

i think the glory day of the syndicates was pre-internet.......... so they had info that wasn't widely available.

syndicate would know that lebron is a late scratch whereas only associated with the game (including local tv/radio) would know that... today the whole world knows it........ and they were getting much more obscure but important info than lebron. like wyoming's star QB being a late scratch.

stock market and betting have many similarities, but many differences too..... irrationality of sports betting is corrected really fast, stock market not so

[Gaze73]

Yes, but with a few caveats.

Simply following the majority won't yield a winning strategy. And, despite what some say, auto fading the public won't yield a winning strategy either.

However, this doesn't mean you shouldn't incorporate it into your modeling. If you are able to decipher when public sentiment is "wise" you'll have a powerful tool at your disposal.

This. Most of my bets are made based purely on what the public does. You observe the crowds long enough and you start seeing patterns which never change, until a virus comes along.

[KVB]

A bit off the subject, but I found fascinating many years ago while I was in an IBM management class. We were given the following exercise.

“NASA Exercise: Survival on the MoonScenario: You are a member of a space crew originally scheduled to rendezvous with a mother ship on the lighted surface of the moon. However, due to mechanical difficulties, your ship was forced to land at a spot some 200 miles from the rendezvous point. During reentry and landing, much of the equipment aboard was damaged and, since survival depends on reaching the mother ship, the most critical items available must be chosen for the 200-mile trip. Below are listed the 15 items left intact and undamaged after landing. Your task is to rank order them in terms of their importance for your crew in allowing them to reach the rendezvous point. Place the number 1 by the most important item, the number 2 by the second most important, and so on through number 15 for the least important.”

Then we randomly divided in groups of 5 and asked to repeat using a group consensus approach (wisdom of the crowd). Needless to say, I found some of the suggestions good and others not. But, we hammered out a list. Then we were given a scoring sheet and we computed our individual score and the team score. I was surprised that the team score was better than mine. The instructor then asked for a show of hands of those who had a better individual score than the team. No one in the class of 30 raised their hand. He said no one rarely does.

Here is a link to the quiz (1^st page), the correct answers (2^nd page), and the scoring method (3^rd page).

https://www.humber.ca/centreforteachingandlearning/assets/files/pdfs/MoonExercise.pdf

I learned a valuable lesson that day.

Thanks Bsims for sharing this. I haven't clicked the link but am interested in trying this. Even at home with the family.

Thanks again.

[Believe_EMT]

Professionals largely do not bet openers so you have basically square bettors.

This might be one of the most dangerous and factually inaccurate things every posted on SBR

[TheLock]

This might be one of the most dangerous and factually inaccurate things every posted on SBR

Yeah my eyes rolled into the back of my head when I first read his post.

[solring]

This might be one of the most dangerous and factually inaccurate things every posted on SBR

I was thinking "stupidest", but your thought is correct, too...

[StackinGreen]

This might be one of the most dangerous and factually inaccurate things every posted on SBR

Why I stopped responding.

[StackinGreen]

This. Most of my bets are made based purely on what the public does. You observe the crowds long enough and you start seeing patterns which never change, until a virus comes along.

A famous investor recently said the only real advantage anyone has anymore, and the one that won't go away and has staying power the way humans are set up is ... irrational exuberance.

[clockwise1965]

A famous investor recently said the only real advantage anyone has anymore, and the one that won't go away and has staying power the way humans are set up is ... irrational exuberance.

Exactly

[Roger T. Bannon]

This might be one of the most dangerous and factually inaccurate things every posted on SBR

The professional bettors I have seen have said they do not want to make the books lines for them. They want to wait until the limits are raised and they can get money down. And that is also why you will see big lines move on a college football Saturday when numbers have been sitting there all week. So there are professionals and then there are professionals.

This also depends on what you consider an opener. Do you consider an opener the BOL opener with a $250 limit or do you consider an open a Las Vegas opener which is not an opener at all.

[Roger T. Bannon]

A famous investor recently said the only real advantage anyone has anymore, and the one that won't go away and has staying power the way humans are set up is ... irrational exuberance.

That is a strange statement to make since the only way you can find value with irrational exuberance is to short a stock or market and I do not know of any famous investors that got to be known as famous investors through shorting as opposed to buying prior to the irrational exuberance.

Another interesting obvious counterfactual here is that if the value in a market is irrational exuberance then a market is not efficient at all and there would be value at all times.

[Roger T. Bannon]

This might be one of the most dangerous and factually inaccurate things every posted on SBR

I have also taken note of the fact that professional bettors not only mock people for betting openers but also mock them for betting overnights. I think if you are betting openers, you are not in the club.

[stevenash]

I have also taken note of the fact that professional bettors not only mock people for betting openers but also mock them for betting overnights. I think if you are betting openers, you are not in the club.

You mention betting openers, if I think the opening overnight line is too soft then yes I will bet it.

Here's my opinion on beating the closing line.
I'm going to use a hypothetical baseball game.
Let's say the White Sox are playing the Twins.
The Twins open up as a +130 road underdog.
I like the Twins in this spot but I want to see how the line flucuates during the course of the day.
The line at noon is now Minnesota +134.
I still haven't pulled the trigger yet.
At 5pm two hours before first pitch Minnesota is +138.
I bet it right there at +138 figuring this will probably be the best odds I'll get.
The game is bet back down to +134 come first pitch at 7:05.
The closing line is +134, I bet it earlier at +138.
Point being doesn't matter when you beat the closer, some think it's imperative to beat the closer right as the game goes off.
(Am I making sense here?)

[Roger T. Bannon]

You mention betting openers, if I think the opening overnight line is too soft then yes I will bet it.

Here's my opinion on beating the closing line.
I'm going to use a hypothetical baseball game.
Let's say the White Sox are playing the Twins.
The Twins open up as a +130 road underdog.
I like the Twins in this spot but I want to see how the line flucuates during the course of the day.
The line at noon is now Minnesota +134.
I still haven't pulled the trigger yet.
At 5pm two hours before first pitch Minnesota is +138.
I bet it right there at +138 figuring this will probably be the best odds I'll get.
The game is bet back down to +134 come first pitch at 7:05.
The closing line is +134, I bet it earlier at +138.
Point being doesn't matter when you beat the closer, some think it's imperative to beat the closer right as the game goes off.
(Am I making sense here?)

Beating the close is of really no importance at all. All that matters is that you are right in your analysis. If you are then you will win.

The concept of beating the close is based on the Wisdom of the Crowd and efficient markets. If you are betting on reality, it would be expected that you would have the line move in your favor as the world sees what you see. If you are seeing something that the world doesn't see, you would not expect the line to move in your favor. Whether it moves in your favor or not is irrelevant except as a measuring stick.

[stevenash]

Beating the close is of really no importance at all. All that matters is that you are right in your analysis. If you are then you will win.

The concept of beating the close is based on the Wisdom of the Crowd and efficient markets. If you are betting on reality, it would be expected that you would have the line move in your favor as the world sees what you see. If you are seeing something that the world doesn't see, you would not expect the line to move in your favor. Whether it moves in your favor or not is irrelevant except as a measuring stick.

Spot on response!

I never got the beat the closing line rhetoric either.
Bottom line is, like you mentioned, is a win.

[Roger T. Bannon]

Spot on response!

I never got the beat the closing line rhetoric either.
Bottom line is, like you mentioned, is a win.

Well, the crowd is very good at figuring out what is going to happen in a sporting event, so if you do not have line value, you are probably wrong. It does not mean you are definitely wrong. If you are betting at close to the close, you obviously have less of a chance of getting value and you are not going to have much line movement regardless.

If you are not getting line value with your bets and winning, you are either extremely good or extremely lucky. You probably are not extremely good.

[Optional]

There is more than one type of sharp bettor.

I would think someone who says they do not want to bet openers simply due to not wanting to help books make lines is definitely not sharp though.

Why cut off your nose to spite your face if you can see there is an edge?

I wonder if, historically, syndicates have a bigger edge than one really great modeler. I imagine yes?

Good question.

[Roger T. Bannon]

There is more than one type of sharp bettor.

I would think someone who says they do not want to bet openers simply due to not wanting to help books make lines is definitely not sharp though.

Why cut off your nose to spite your face if you can see there is an edge?




Good question.

Because they stand to make more money by not moving the line. If you are a professional bettor, you know if you bet $500 on a game and the line moves 1 point, you have destroyed all your value. Better to wait until you can get money down and hope that the number is still there.

So a person that bets thousands per game just waits to see what is available when they can bet as much as they want. Then they hit what is there to hit. If they can make what they want, they will bet it earlier.