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This is the introductory definitions of two different types of probability:
I am only familiar with the first concept, probability based on the empirical evidence (for example a statiscial survey may help approximate the probability of a person holding a certain opinion), or determined with knowledge of all factors which can affect the outcome (for example a thought experiment by flipping a perfect coin, e.g. the unit disc thrown on a plane).
Bayesian probability states that there is a certain probability to every statement. I find this hard to justify, given that many statements is either true or false. For example, how can one determine the probability that there is 4 apples in a given basket? The statement becomes: "A: The basket b contains 4 apples". Do bayesian probability state that this true or non-true statement has a probability value attached to it, so that [tex]0 < P(A) < 1[/tex] based on a degree of belief? [tex]P(A)[/tex] should in my opinion be equal to either 1 or 0, determined by the truth of the statement. The probability that a basket chosen arbitrarily contains 4 apples is another thing. The statement becomes: "B: An arbitrarily chosen basket contains 4 apples". This, however does have a probability value [tex]0 \leq P(B) \leq 1[/tex] attached to it. I can agree that bayesian probability makes sense accompanied with extensive statistical data, but to point to a certain case which is either true or false - isn't it formally wrong to assign a probability value to it?
The above may be hair-splitting (in a practical sense), but my problem comes when bayesian probability is expanded to statements regarding the truth of undeterminable events, such as the existence of ghosts, angles, etc. When one places a probability value to a statement that is by definition undeterminable, how can this be justified by the degree of one's belief?
Frequentists talk about probabilities only when dealing with experiments that are random and well-defined. The probability of a random event denotes the relative frequency of occurrence of an experiment's outcome, when repeating the experiment. Frequentists consider probability to be the relative frequency "in the long run" of outcomes.[1]
Bayesians, however, assign probabilities to any statement whatsoever, even when no random process is involved. Probability, for a Bayesian, is a way to represent an individual's degree of belief in a statement, given the evidence.
I am only familiar with the first concept, probability based on the empirical evidence (for example a statiscial survey may help approximate the probability of a person holding a certain opinion), or determined with knowledge of all factors which can affect the outcome (for example a thought experiment by flipping a perfect coin, e.g. the unit disc thrown on a plane).
Bayesian probability states that there is a certain probability to every statement. I find this hard to justify, given that many statements is either true or false. For example, how can one determine the probability that there is 4 apples in a given basket? The statement becomes: "A: The basket b contains 4 apples". Do bayesian probability state that this true or non-true statement has a probability value attached to it, so that [tex]0 < P(A) < 1[/tex] based on a degree of belief? [tex]P(A)[/tex] should in my opinion be equal to either 1 or 0, determined by the truth of the statement. The probability that a basket chosen arbitrarily contains 4 apples is another thing. The statement becomes: "B: An arbitrarily chosen basket contains 4 apples". This, however does have a probability value [tex]0 \leq P(B) \leq 1[/tex] attached to it. I can agree that bayesian probability makes sense accompanied with extensive statistical data, but to point to a certain case which is either true or false - isn't it formally wrong to assign a probability value to it?
The above may be hair-splitting (in a practical sense), but my problem comes when bayesian probability is expanded to statements regarding the truth of undeterminable events, such as the existence of ghosts, angles, etc. When one places a probability value to a statement that is by definition undeterminable, how can this be justified by the degree of one's belief?
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