Undergrad Probability paradox: P(X=x)=1/n >1

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SUMMARY

The discussion centers on the probability paradox involving a random variable X uniformly distributed in the range (0, n) where n < 1. The equation P(X=x) = 1/n > 1 is identified as a violation of the fundamental law of probability, which states that probabilities must not exceed 1. Participants clarify that P(X=x) represents a probability density function, which can exceed 1, while the integral of this function must remain at or below 1. The correct interpretation is that P(X=x) is always zero, and the density function should be understood in terms of intervals rather than point probabilities.

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Trollfaz
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I have a random variable X in range(0,n) where n<1, with a uniform distribution
Then the probability of sample space S=n x P(X=x) x<=n which must be 1
Manipulating the equation P(X=x)=1/n >1
Then this violates the fundamental law of probability which says that any probability must be at most 1.
How do we resolve this paradox here
 
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Are you assuming that the maximum value a probability density function may take is ##1##?

That's certainly not the case.
 
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Trollfaz said:
Then this violates the fundamental law of probability which says that any probability must be at most 1.
You are confusing a probability density with a probability. The function you are describing is the probability density function and it can be arbitrarily large. The integral of a probability density is a probability. So only its integral must be no greater than 1, which is the case.
 
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Just to say it explicitly, P(X=x) is always zero. ##P(|X-x|<\epsilon)\approx 2\epsilon f(x)## is the right interpretation of the density function
 
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Trollfaz said:
I have a random variable X in range(0,n) where n<1, with a uniform distribution

If you had a uniform rod of mass 1 kg and length 1/2 meter, the density of the rod would be 2 kg per meter, even though the rod only has mass 1 kg. As the others pointed out, probability density is not the the same concept as probability.
 
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An off-topic discussion has been deleted, and since the OP's question has been answered, this thread is now closed. Thanks folks.
 
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If there are an infinite number of natural numbers, and an infinite number of fractions in between any two natural numbers, and an infinite number of fractions in between any two of those fractions, and an infinite number of fractions in between any two of those fractions, and an infinite number of fractions in between any two of those fractions, and... then that must mean that there are not only infinite infinities, but an infinite number of those infinities. and an infinite number of those...

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