What Is The Statistical Probability That All Sightings Are False?

[indiefoot]

It's not just a belief system. We are talking about probability. :

How many reports have been proven true? zero out of many thousands. (and you would have to agree, I think, that many have been proven false).

If we use the same standard of proof as we do for true, how many reports have been "proven" false. How exactly would you do that? Just because you and I and all the rest of the Bff think a report is false, that doesn't make it false. It isn't "proven" false.

So the possibility still exists that all can be false. According to probability theory, that possibility becomes larger with every false report. Again, you can believe whatever you wish, you can talk in layman's terms about likelihoods of this or that. but you shouldn't confuse your belief with probabiilty in the numerical sense of the word. That is what causes much of the confusion. The OP was about "statistical probability."

What happens to your probability theory when you can't "prove" a report is false?

The other part of the confusion comes about because of a lack of understanding of probability theory: To restate what I have said a number of times, you cannot assume a probability and then do the (1-p)^n thing. It doesn't apply in this setting, because you don't know p; this is not dice rolling, or shooting baskets, or flipping coins. Evidential probability theory applies, and says regardless of the probability you start off believing, as each trial is negative, the chance that all will be negative, increases.

Incidentally, when I watch Finding Bigfoot town hall meetings, I see numerous little children claiming to have seen bigfoot. What do you think of the likelihood that they are telling the truth? why do you think they are raising their hands?

p.

I would not be surprised to find out that many reports are indeed false, but that is a world of difference from being able to prove it. Of course these are just a layman's thoughts.

[Guest]

JDL wrote:

It's not just a belief system. We are talking about probability. :

How many reports have been proven true? zero out of many thousands. (and you would have to agree, I think, that many have been proven false).

So the possibility still exists that all can be false. According to probability theory, that possibility becomes larger with every false report. Again, you can believe whatever you wish, you can talk in layman's terms about likelihoods of this or that. but you shouldn't confuse your belief with probabiilty in the numerical sense of the word. That is what causes much of the confusion. The OP was about "statistical probability."

The other part of the confusion comes about because of a lack of understanding of probability theory: To restate what I have said a number of times, you cannot assume a probability and then do the (1-p)^n thing. It doesn't apply in this setting, because you don't know p; this is not dice rolling, or shooting baskets, or flipping coins. Evidential probability theory applies, and says regardless of the probability you start off believing, as each trial is negative, the chance that all will be negative, increases.

Incidentally, when I watch Finding Bigfoot town hall meetings, I see numerous little children claiming to have seen bigfoot. What do you think of the likelihood that they are telling the truth? why do you think they are raising their hands?

p.

The irony! You don't seem to understand evidential probability yourself. There is no difference between an increasing number of unconfirmed reports affecting the likelihood that bigfoot does not exist versus an increasing number of reported sightings affecting the likelihood that they do. Both use the same methods in compound probability, which are influenced by the size of the sample set. So how exactly are you evaluating whether a report is false? And what happened to the weak coffee analogy? You can't have it both ways.

Edited February 28, 2012 by Gigantofootecus

[Guest Kerchak]

I think Unicorns & Leprechauns are actually more believable....

Good grief.

[Guest parnassus]

g,

I love how you seem to stalk my posts. Some would think it creepy, but I am just flattered. However, your responses are generally just cryptic and you don't seem to provide much information other than cryptic crabiness and straw men. Again, I repeat, please respond to my PM's.

Speaking of which, I don't know anything about the weak coffee thing, I think you are confusing me with someone else.

If you don't think there are reports that have been proven false, I think you are in error. Take it up with the BFRO, Peter Byrne, or any other organization that investigates reports.

There certainly are no reports that have been proven true.

If you would like to try to educate the forum on evidential probability theory, please go ahead, I have tried. Since you claim to have knowledge of this area, I invited you to do so and I continue to do so. ProTip: It's a "fool's errand."

The bottom line is that if one is looking for 'statistical probability'

1) (1-p)^n cannot be used in the case where p is not objectively known. In this case, it is not known that there is a bigfoot, so p may be zero.

and

2) in this situation, one can only subjective postulate a prior p. Regardless of what p one suggests, with every proven false report the posterior probability of a true report does not increase, it decreases.

I realize you are not a statistician, but please provide a coherent statement of your stance on this issue, rather than posting cryptic headscratchers. Here are the bottom line questions I put to you. If you do not answer them yes or no I can only assume that you grant my position.

Is it your position that (1-p)^n can be used to calculate the "statistical probability" that all reports are false.? yes or no. my position is no.

Do you think that proven false reports exist? yes or no. My position is yes.

Do you think that proven true reports exist? yes or no. my position is no.

Do you think that each proven negative report increases the probability that all reports are false? yes or no. my position is yes.

those are the essential questions. Please answer, and please answer my PM's.

p.

[indiefoot]

parnassus,

What is your standard of proof for labeling a report false?

What would your standard of proof be to label a report true?

Would they be the same standard of proof?

[Drew]

Any sighting of Bigfoot is false based on the fact that the existence of a bipedal hairy creature has not been proven.

Therefore the probability that all sightings are false is 100%.

However, many sightings are not lies or hoaxes. I believe a percentage of sightings are the result of sleep disorders, mental illnesses, and/or the effects of prescription drugs. These sightings are false, but are not deception. Many of these sightings are also related with embellishment, making a benign dark object into a hairy beast.

[indiefoot]

I've thought much the same thing about some posts that I've seen.

This should apply nicely

Argument from ignorance

The argument from ignorance, also known as argumentum ad ignorantiam or argument by lack of imagination, is a logical fallacy in which it is claimed that a premise is true only because it has not been proven false, or that a premise is false only because it has not been proven true.

Edited February 29, 2012 by indiefoot

[Guest]

Bigfoot sightings where the person saw Bigfoot prove the probability of those sightings being true 100%. Those sightings proved the existence of a bipedal hairy creature. Percentages of these sightings may be attributed to hunting,hiking, driving and the affects of sobriety, awareness and good vision.

[Guest]

Any sighting of Bigfoot is false based on the fact that the existence of a bipedal hairy creature has not been proven.

Therefore the probability that all sightings are false is 100%.

However, many sightings are not lies or hoaxes. I believe a percentage of sightings are the result of sleep disorders, mental illnesses, and/or the effects of prescription drugs. These sightings are false, but are not deception. Many of these sightings are also related with embellishment, making a benign dark object into a hairy beast.

Ah what logic, you commence with a premise which should in logic be the conclusion so you are stuck in a paradox.

Your basic argument is based on something you hold as absolute fact that BF has never been proven so any sighting of bigfoot must be false. Wow what an insular and problematic argument.

Lets see this type of argument in scenarios proving it problematic. Before Barak Obama became president there had never been a black male American president in America. According to your argument, if you were utilising it say in 1990, you would say as its never been proven a black man can be president therefor all who speak of witnessing a black man being US president are bearing false witness.

Lets go further with this as its fun, Say you were living in Leonardo Da Vinci's day , you could say its never been proven humans can make machines to fly therefor anyone who says they have built such a machine is speaking falsely (Leonardo Da Vinci did in fact create a machine to help humans fly long before the aeroplane or helicopter).

Not too long ago in history you could have said its never been proven that an animal fitting the descriptor of a gorilla exists therefor all who say they have sighted one are providing false sightings ( how are you going with this logic now....)

Columbus could have said, well its never been proven that a land like the continent of America exists, so all those reports from sailors in the past are false reports possibly due to increase in drinking or malnutrition at sea.

Shall I go on.. ?

Wow feel like Im watching a woman being drowned by the kings men to see if she floats - if she floats they will burn her for being a witch, if she drowns then she wasnt one after all so its Ok ... when I read your classic logic flaw (as taught in advanced logic)...

This is wonderful for logic teachers pointing out how a false premis leads to a false conclusion

It is a fact that the existance of BF has never been proven

Ergo

Any Sighting of Bigfoot is false

Back to the flat earth and witch burning I guess ...

If it isnt clear by the way, lets go back to the Gorilla example as it really has direct relevance... your argument is insular and circular leaving no leeway for the loopholes within it. Ill follow it through for you,

Its never been proven Gorillas exist

All sightings of Gorillas must therefore be false sightings (though not necessarily puposefully decieptfull)

They must be false because of the fact its never been proven Gorillas exist

Gorillas therefor cant be proven to exist, because all sightings of Gorillas are false

Edited February 29, 2012 by Encounter

[Guest]

g,

I love how you seem to stalk my posts. Some would think it creepy, but I am just flattered. However, your responses are generally just cryptic and you don't seem to provide much information other than cryptic crabiness and straw men. Again, I repeat, please respond to my PM's.

I doubt you are flattered that I am stalking you. Do you think you are the only poster I respond to? I just call BS when I hear it. How are my posts any different that yours to other members? I respond in kind.

Speaking of which, I don't know anything about the weak coffee thing, I think you are confusing me with someone else.

If you don't think there are reports that have been proven false, I think you are in error. Take it up with the BFRO, Peter Byrne, or any other organization that investigates reports.

The weak coffee analogy is the party line for most debunkers. The number of reports apparently is inconsequential.

There certainly are no reports that have been proven true.

If you would like to try to educate the forum on evidential probability theory, please go ahead, I have tried. Since you claim to have knowledge of this area, I invited you to do so and I continue to do so. ProTip: It's a "fool's errand."

It's not complicated. We must weigh each report before applying evidential probability theory. Small weights reduce the likelihood that the premise is true.

The bottom line is that if one is looking for 'statistical probability'

1) (1-p)^n cannot be used in the case where p is not objectively known. In this case, it is not known that there is a bigfoot, so p may be zero.

Depends on the hypothesis you are testing, or is that too cryptic for you?

and

2) in this situation, one can only subjective postulate a prior p. Regardless of what p one suggests, with every proven false report the posterior probability of a true report does not increase, it decreases.

You don't seem to get the similarity between this and the premise that "with every report the posterior probability of a true report increases." They are both exercises in compound probability. This is what I've been on about with you. But you don't seem to follow.

I realize you are not a statistician, but please provide a coherent statement of your stance on this issue, rather than posting cryptic headscratchers. Here are the bottom line questions I put to you. If you do not answer them yes or no I can only assume that you grant my position.

I'm certain I've had more stats training than you have. I took all that was offered at the university I attended, which was a large component of the computer science curriculum.

Is it your position that (1-p)^n can be used to calculate the "statistical probability" that all reports are false.? yes or no. my position is no.

No. The evidential reports must be weighted. I never disputed that. But it does depend on the hypothesis being tested.

Do you think that proven false reports exist? yes or no. My position is yes.

Sure. What's your % estimate?

Do you think that proven true reports exist? yes or no. my position is no.

Silly question. If the reports were proven true, then bigfoot would be confirmed to exist, which is obviously not the case.

Do you think that each proven negative report increases the probability that all reports are false? yes or no. my position is yes.

No more than I think that the number of reports increases the probability that at least 1 report is true.

Oh and BTW, you got mail.

Edited February 29, 2012 by Art1972
edited to remove 1A rule violation....

[Guest]

Simple answer to op question. Zero. Might as well close this topic.

[Guest Knuck]

To someone who does not know the truth, there can be all kinds of speculation as to statistical probability of falsehood in all reports. However, in reality, there is no such statistical probability, as Sasquatch do exist, and some mearly need to consider themselves as uninformed/uneducated as to the actual facts.

There may be statistical probability as to how many claims are false, and how many are indeed real and true. -Knuck

[JDL]

Any sighting of Bigfoot is false based on the fact that the existence of a bipedal hairy creature has not been proven.

Therefore the probability that all sightings are false is 100%.

By this reasoning, if someone is present when a tree falls in a forest and tells you that there was sound, but cannot prove it to you, you can claim that the probability that all claims that a tree makes noise when it falls are false is 100%.

You cannot "prove" that all reports are false, but you "believe" it to be so, and then you try to tell us that we should believe what you believe. How are you different from someone that wants you to believe in bigfoot simply because they believe in bigfoot?

[Drew]

I can certainly prove that at least ONE report of a tree falling and making noise is true, however. I can't do that with Bigfoot sightings.

When you can prove ONE TIME that a bigfoot sighting is true, then I will have to revise the probability. It is this little ZERO in proven column, that drives the probability to an infinite parabolic.

[Incorrigible1]