What Is The Statistical Probability That All Sightings Are False?

[Guest]

Indie:

what makes you think that "fear and confusion" indicate clear thinking? Fear is one of the most frequent causes of eyewitness error.....and confusion? are you serious? you really think "confusion" is a marker for reliability?

Research would suggest that the witness shapes his account to the expectations of the questioner; so first hand questioning by a bigfoot believer will be much more likely to elicit a description of a bigfoot (whatever that is).

Read the work of Barbara Tversky and Elizabeth Loftus.

p.

Parnassus, not that I generally reply to you as you seem to only have one agenda on the forum... but just to say, you do know how lie detectors work dont you? If a first hand witness spoke of standing face to face with a BF for the first time in their lives and didnt have a good measure of clear emotional trauma or exitment showing, that is when you might think their story fake - not the other way around!

[Guest MikeG]

Encounter, you're trying to have it both ways. You ask about inclusion in stats. Stats is stuff we can count, in our reality, in our mono-directional time, in our 3 or 4 dimensional world. You can't go count stuff in some other dimension, or time, and come back and put it in our records in any meaningful way. However much you wish it.

Tell me which column we're going to put griffons in? And ****, those pesky unicorns are so difficult to count.

Mike

[Guest]

Mike, its interesting that in the past you have seemed to say that you are objective and dont have any presuppositions in BF research - yet you seem awash with presuppositions and things already invalidated in your mind.

I mentioned previously the concept of root assumptions concerning reality. Rood assumptions are assumptions one has about existance unquestioned - that they so strongly believe they no longer recognise it is a belief not a fact. One then experiences their everyday world reflected to a great extent by those root assumptions. You feel your example of griffins is good because you take it for granted that these must be mythology and for you mythology is not something bespeaking reality. In fact an open mind might say Griffins could well have been a reality in the way you experience reality and also a part of mythology.

Your concepts of reality are presumptions, not fact Mike, nor are they in any way actually objective. You were brought up in a society with certain beliefs and you accept a good part of such beliefs as actual, factual, true. Some question much more deeply and it is only ever such questioners who have come to move society from root assumptions quite detrimental.

I have said it all before but the world being flat was a root assumption, the earth being centre of the universe was a root assumption, black people being less intelligent than whites was a root assumption, time being linear is a root assumption, you cant change the past is a root assumption, griffens not being real is a root assumption, men being more logical than women is a root assumption, women being more intuitive than men is a root assumption, youll catch a cold if you dont put clothes on is a root assumption, western science is more knowledgable than indigenous understandings of our cosmology is a root assumption and, the idea the only acceptable witnesses of BF are scientists gathering data is a root assumption.

Those who questioned root assumptions have brought the west out of practices of slavery (to some extent), got politicians to recognise the destruction humans have been creating on earths environment, have gotten women the vote, have recognised black or white skin is not a measure of intelligence and have for many people awakened an understanding that one being is not superior to another. But this all falls on barricaded ears

Edited February 13, 2012 by Encounter

[Guest exnihilo]

Sounds like you are describing "schemas."

http://en.wikipedia....ma_(psychology)

A schema (pl. schemata or schemas), in psychology and cognitive science, describes any of several concepts including:

An organized pattern of thought or behavior.

• A structured cluster of pre-conceived ideas.
  
• A mental structure that represents some aspect of the world.
  
• A specific knowledge structure or cognitive representation of the self.
  
• A mental framework centering on a specific theme, that helps us to organize social information.
  
• Structures that organize our knowledge and assumptions about something and are used for interpreting and processing information.
  

A schema for oneself is called a "self schema". Schemata for other people are called "person schemata". Schemata for roles or occupations are called "role schemata", and schemata for events or situations are called "event schemata" (or scripts).

Schemata influence our attention, as we are more likely to notice things that fit into our schema. If something contradicts our schema, it may be encoded or interpreted as an exception or as unique. Thus, schemata are prone to distortion. They influence what we look for in a situation. They have a tendency to remain unchanged, even in the face of contradictory information. We are inclined to place people who do not fit our schema in a "special" or "different" category, rather than to consider the possibility that our schema may be faulty. As a result of schemata, we might act in such a way that actually causes our expectations to come true.

The concept of schemata was initially introduced into psychology and education through the work of the British psychologist, Frederic Bartlett (1886–1969).^[1] This learning theory views organized knowledge as an elaborate network of abstract mental structures that represent one's understanding of the world. Schema theory was developed by the educational psychologist R. C. Anderson. The term schema was used by Jean Piaget in 1926, so it was not an entirely new concept. Anderson, however, expanded the meaning.^[2]

People use schemata to organize current knowledge and provide a framework for future understanding. Examples of schemata include Rubric (academic), social schemas, stereotypes, social roles, scripts, worldviews, and archetypes. In Piaget's theory of development, children adopt a series of schemata to understand the world.

[emphasis added]

Edited February 13, 2012 by exnihilo

[Guest]

Will add to my vocabulary, thankyou!

[Guest exnihilo]

Perhaps the greater half of the BF phenomenon is a problem for cognitive science rather than cryptozoology. And in case it wasn't clear, I reckon the debate itself to be a part of the phenomenon.

Both sides.

[Guest]

I'm curious though, Saskeptic, whence do you think the alleged hallucinatory nature of forests originates?

Way outside my area of expertise, but here's something I think is relevant.

"Bigfoot" is a folklore associated with remote, wild, and forested places. (Whether or not you accept a real, biological bigfoot we can hopefully agree on that much - there is a bigfoot folklore.) One way to participate in that folklore is to spin a yarn about being someplace way off the beaten path and encountering a bigfoot there. It can even be a form of one-upsmanship to report a bigfoot to your mining/trapping buddies, the ladies you find in the taverns, the "greenhorns" and "tenderfoots" in the cities, etc. A big part of this particular folklore is that there's no wink and nod, no giveaway at the end: the point is to make your encounter as credible as possible, either by being completely deadpan in your delivery or going out of your way to be dramatic about how negatively the experience has affected you.

Such stories have been handed down from teller to teller, and there's no way to distinguish them from those of people who might actually have encountered real bigfoots. They also can "prime" a person to be thinking about something - even subconsciously - when they find themselves in a particular situation. Since I was a boy and first saw the PGF, I have been unable to visit a forested stream without thinking what a great place it would be to find a bigfoot. When I say "hallucination", this is the kind I mean: someone with a subconscious idea who could find themselves experiencing things that the mind assembles as "bigfoot." I think Dr. Johnson's encounter is a classic example of this, but please let's not drag that discussion into this thread because it's been fully discussed elsewhere.

Anyway, I think it takes little more than for the meme of bigfoot to be that it's most often found in remote forests to result in a vast majority of reported encounters coming from remote forests. This is the setting in which tall tale tellers place their tales, it's where people can hallucinate/misidentify things as bigfoot that have other explanations, it's where people are more likely to hoax bigfoot, etc. So I don't see any more legitimacy to the spatial correlation of bigfoot reports and forest cover/rainfall than I do in the 100% correlation between lake monsters and lakes.

Again, this doesn't mean that bigfoot doesn't exist, it only means that a positive correlation between bigfoot reports and rainfall amounts doesn't prove that it does.

[Guest]

The reports are not data, they are "intelligence" reports, much like the reports from a wiretap, they are reports of experiences, subjective not objective, as a boundary, you can say that if one report is true out of the 4000 plus online, then statistics don't matter. Perceptual failure will always be seen by most as the most likely cause of a report, (Hoaxing) Nevertheless, determining the probability of a sighting report's "truth value" is an intelligence type problem, not a science problem. Check with the NSA. They probably have data on the truthfulness of the 4000 plus witnesses right now from facebook alone, that is,... if they cared. You can narrow the problem space by determining that you would need a multi-generational multi person hoaxing group to produce all the reports, because of the span of time and space involved. There are 5 possible causes of sighting reports: 1) Hoaxing, 2) Misidentified animal, 3) perceptual failure, 4) mass halucination, 5) actual sightings of an unknwn animal. The probability of any one sighting report being caused by any one of these causes, needs one to partition the causes into some sort of multinomial expression, I.E., you have to figure out what the probability of a sighting report is for each of these causes in a zero sum game. (all of them together sum to 100%). The overall probability of a sighting report being due to a sighting of an unknown animal, is given by the expression X = number of animals in a defined area, time Y = the number of observers in the same defined area. The probability of a sighting report coming from a given area caused by the sighting of an actual unknown animal is given by X * Y = P But this does not answer your question about the probability of the sighting report being caused by the other 4 possibilities. You can narrow the problem space further by pointing out that the PG film narrows the space to 2 possibilities, 1) it's a hoax (guy in a gorilla suit) or 2) it's an unknown animal, beccause the existence of the PG film makes the possibility of mass halucination of perceptual failure get small for sighting reports in general. So figuring out the probability that it's a hoax is the biggest problem. So how likely is it that all of them are hoaxes is a good question, to which we do not know the answer. We all know there are some hoaxers out there, but how many? How many al-quaida are out there anyhow?

Well said, Tsiatko. I agree that this is a compound probability problem and weighting the possibilities is problematic. We need to apply stats just to obtain an estimate for the weights used to estimate an ans for the OP. For example, we should have a look at the report databases to see if they conform to the expected distribution of a real creature. Use a cluster analysis to look for anomalies, which tend to indicate the level of hoaxing.

Take the foot cast study that showed a near normal distribution for example. If it wasn't "near" normal, then that would have been damning. A purely normal distribution would also be suspect, since we know that hoaxing/misidentifications must be in the mix. It also would have been damning if there was no reference to bigfoot in indigenous cultures. The fact that there is doesn't prove bigfoot is real, but it would have been suspect if it was absent.

What I'm getting at, is that these statistical analyses are more likely to rule out bigfoot than rule him in. However, I haven't seen one yet that has ruled them out. I suspect that the foot cast distribution would have looked very different if 100% of the casts were faked. I'm sure there are some misidentified children in the mix, but what is the likelihood that barefoot children account for all the "littlefeet" casted? Any way you slice it, there are a significant number of reports (and likely many non-reported encounters) and we already have to apply a very small weight to the likelihood of every single report being false to rule out bigfoot. This is an unprecedented phenomena either way. (UFOs aside, which is also an unresolved issue).

Edited February 13, 2012 by Gigantofootecus

[Guest parnassus]

It takes something special to conclude and then try to convince the world that every person who has reported a sighting is either prone to hallucination; is unable to distinguish the difference between a bigfoot and a man, bear, etc.; or is a liar.

Obviously, by whatever metric you choose, as long as the possibility that bigfoot exists is assigned a value greater than zero, the probability that all reports are false diminishes with each added report.

Each die in a set of Yahtzee dice has six sides and six numbers. If I roll one of these die, the chance that I do not roll a six is five out of six, or 0.8333. If I roll all five dice, the chance that no six comes up on any one of them is 0.8333 x 0.8333 x 0.8333 x 0.8333 x 0.8333 = 0.4019.

Where bigfoot is concerned, however, skeptics' dice don't have sixes. On that face of the die is a zero. So when I roll a die, the chance that a six does not come up is 100%, and it remains 100% no matter how many die I roll or for how long.

So the real problem is that many skeptics emphatically refuse to assign a value greater than zero to the possibility that bigfoot exists. To them it is impossible until you produce a body. Once they are forced to acknowledge that bigfoot exist, then they'll be happy to assign a value greater than zero and discuss the statistical probability of how many reports are accurate.

For the more open-minded, though, even if you say that 99 out of 100 reports are false, and you have 1000 reports, the chance that every single one of them is false is 0.000043, or 0.0043%

Please consider the absolute number of people in America who sometimes lie for amusement or attention, are subject to hallucinations, are alcoholics, don't know how to identify wildlife, have poor eyesight, who are easily panicked or persuaded or suggestible, or sometimes make mistakes in the dark or unfamiliar circumstances, or are pranked by others. I have, and think you will find it FAR exceeds the number of bigfoot "reporters". Furthermore, your best friends, neighbors, relations and respected others all fall in these categories. And so, wadr, do you.

To get to the issue of probability theory:

wadr, your examples show you don't understand probability theory. This is not physical aka frequency probabiity, like throwing dice or flipping coins where random events occur with a certain known probability. Your mathematical model does not apply. It cannot be used. You can't put a square peg in a round hole.

Let me describe something that would be closer to the way the problem would be approached using evidential probability theory (the math is completely different): you are given a box with a billion balls in it, and told that there are some white balls, and there might be red balls but there might not. You are told that the balls have been mixed and shaken and thoroughly randomized. You are told to blindly pull out balls one at a time and after each ball, to estimate the chances that the next ball will be red, or that a red one will ever come out. The first one you pull out is white, and after you pull out 50, then 100, then 1000, and you find no red balls, what are you thinking? Do you think that the odds are getting better that there are some red balls in there? or do you think the chances are getting smaller with each white ball? After 500,000 white balls, what are you thinking? after 5 million? after 50 million white balls and no red ones? after 500 million?

Evidential probability theory tells us, and I'm sure you would agree, that (since you weren't guaranteed that there were any red balls) with each ball that comes out white, the chances decrease that there are any colored balls in the box. Now everyone will say, you don't know for absolute sure that there aren't any red balls until you pull out the very last of the billion balls? True, and that is what I would say also. The possibility will always remain that there is a red ball, until the supply of balls runs out, but it gets smaller and smaller as the flow of white balls continues.

That isn't a perfect description of the bigfoot sightings issue, I realize, but I hope it illustrates the idea of evidential probability. If that is helpful, good, if not, study up on probability theory for a more rigorous treatment of the subject. But please, don't use the dice rolling stuff any more. It is just not applicable.

p.

Edited February 13, 2012 by parnassus

[Guest]

Perhaps the greater half of the BF phenomenon is a problem for cognitive science rather than cryptozoology. And in case it wasn't clear, I reckon the debate itself to be a part of the phenomenon.

Both sides.

Agree to some extent.

I think that throughout history we have been trying to see past the veil, face our fears, brave vaster journeys concerning our reality or existance - the BF question tantalises many as it is the spoken unspoken within the parametres we place upon ourselves.

[Guest]

To add to Bobby's sentiments....0% chance! There are probably a high number of false reports, hoaxes, misidentifications, but they are real, so there is no chance that they are all false.

[JDL]

Please consider the absolute number of people in America who sometimes lie for amusement or attention, are subject to hallucinations, are alcoholics, don't know how to identify wildlife, have poor eyesight, who are easily panicked or persuaded or suggestible, or sometimes make mistakes in the dark or unfamiliar circumstances, or are pranked by others. I have, and think you will find it FAR exceeds the number of bigfoot "reporters".

wadr, you don't understand probability theory. This is not physical probabiity, like throwing dice or flipping coins where random events occur with a certain known probability. Your mathematical model does not apply. It cannot be used. You can't put a square peg in a round hole.

Let me describe something that would be closer to the way the problem would be approached using evidential probability theory (the math is completely different): you are given a box with a billion balls in it, and told that there are some white balls, and there might be red balls but there might not. You are told that the balls have been mixed and shaken and thoroughly randomized. You are told to blindly pull out balls one at a time and after each ball, to estimate the chances that the next ball will be red, or that a red one will ever come out. The first one you pull out is white, and after you pull out 50, then 100, then 1000, and you find no red balls, what are you thinking? Do you think that the odds are getting better that there are some red balls in there? or do you think the chances are getting smaller with each white ball? After 500,000 white balls, what are you thinking? after 5 million? after 50 million white balls and no red ones? after 500 million?

Evidential probability theory tells us, and I'm sure you would agree, that (since you weren't guaranteed that there were any red balls) with each ball that comes out white, the chances decrease that there are any colored balls in the box. Now everyone will say, you don't know for absolute sure that there aren't any red balls until you pull out the very last of the billion balls? True, and that is what I would say also. The possibility will always remain that there is a red ball, until the supply of balls runs out, but it gets smaller and smaller as the flow of white balls continues.

That isn't a perfect description of the bigfoot sightings issue, I realize, but I hope it illustrates the idea of evidential probability. If that is helpful, good, if not, study up on probability theory for a more rigorous treatment of the subject. But please, don't use the dice rolling stuff any more. It is just not applicable.

p.

I like this and I feel it illustrates my point regarding the ultimate disconnect being due to a divergence in the underlying assumptions or, if you will, difference in perspectives.

If someone begins from the perspective that bigfoot is unlikely to, or does not exist, then evidential probability theory applies.

If, however, someone has actually had an encounter, it would be the equivalent of getting a sneak peek inside the box and seeing that it does, indeed, contain some red balls. Beginning with a different perspective leads to different expectations regarding outcome.

The third case is that someone pulls you aside and tells you that they've seen inside the box and that it contains some red balls. Now it comes down to trust and whether or not you accept or dismiss the information and its source.

[Guest]

Please consider the absolute number of people in America who sometimes lie for amusement or attention, are subject to hallucinations, are alcoholics, don't know how to identify wildlife, have poor eyesight, who are easily panicked or persuaded or suggestible, or sometimes make mistakes in the dark or unfamiliar circumstances, or are pranked by others. I have, and think you will find it FAR exceeds the number of bigfoot "reporters".

wadr, you don't understand probability theory. This is not physical probabiity, like throwing dice or flipping coins where random events occur with a certain known probability. Your mathematical model does not apply. It cannot be used. You can't put a square peg in a round hole.

Let me describe something that would be closer to the way the problem would be approached using evidential probability theory (the math is completely different): you are given a box with a billion balls in it, and told that there are some white balls, and there might be red balls but there might not. You are told that the balls have been mixed and shaken and thoroughly randomized. You are told to blindly pull out balls one at a time and after each ball, to estimate the chances that the next ball will be red, or that a red one will ever come out. The first one you pull out is white, and after you pull out 50, then 100, then 1000, and you find no red balls, what are you thinking? Do you think that the odds are getting better that there are some red balls in there? or do you think the chances are getting smaller with each white ball? After 500,000 white balls, what are you thinking? after 5 million? after 50 million white balls and no red ones? after 500 million?

Evidential probability theory tells us, and I'm sure you would agree, that (since you weren't guaranteed that there were any red balls) with each ball that comes out white, the chances decrease that there are any colored balls in the box. Now everyone will say, you don't know for absolute sure that there aren't any red balls until you pull out the very last of the billion balls? True, and that is what I would say also. The possibility will always remain that there is a red ball, until the supply of balls runs out, but it gets smaller and smaller as the flow of white balls continues.

That isn't a perfect description of the bigfoot sightings issue, I realize, but I hope it illustrates the idea of evidential probability. If that is helpful, good, if not, study up on probability theory for a more rigorous treatment of the subject. But please, don't use the dice rolling stuff any more. It is just not applicable.

p.

Once you are finished playing with your balls, what are they supposed to represent? Days gone by without BF being classified? Number of reports without BF being classified? Liars? Beggars? Thieves? Bayesian probability? Please explain.

[indiefoot]

Indie:

what makes you think that "fear and confusion" indicate clear thinking? Fear is one of the most frequent causes of eyewitness error.....and confusion? are you serious? you really think "confusion" is a marker for reliability?

Research would suggest that the witness shapes his account to the expectations of the questioner; so first hand questioning by a bigfoot believer will be much more likely to elicit a description of a bigfoot (whatever that is).

Read the work of Barbara Tversky and Elizabeth Loftus.

p.

When someone shows believable emotion when they recall an event that was truely upsetting to them it helps you to believe that what they are telling you is the truth as they remember it.

Clear thinking and lack of confusion during a Bigfoot encounter?

What kind of response do you get when you question witnesses in person?

[Guest]

When someone shows believable emotion when they recall an event that was truely upsetting to them it helps you to believe that what they are telling you is the truth as they remember it.

1) telling the truth as remembered does not make what one remembers the truth

2) liars, or as most people know them "actors," are actually quite skilled at conveying emotion about things that did not actually happen.

Thus, while an emotional witness should not be dismissed out of hand, there is nothing about being emotional or seeming believable that makes the witness' story factually accurate.