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October 21st, 2017, 09:36 AM   #1
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Can Probability density functions take negative values?

My question is: evaluate the pdf at fx(3) where fx(x)=(-2)/((1+x)^3) and compute value -1/32, can pdf's be negative or have i made a mistake in the previous question? Thanks!
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October 21st, 2017, 09:40 AM   #2
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pdf's can't be negative anywhere in their support.

you've made a mistake somewhere.
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October 21st, 2017, 02:25 PM   #3
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Quote:
Originally Posted by Jaket1 View Post
My question is: evaluate the pdf at fx(3) where fx(x)=(-2)/((1+x)^3) and compute value -1/32, can pdf's be negative or have i made a mistake in the previous question? Thanks!
Your f(x) is impossible. The definition of a density function requires it to be non-negative for all x and integrate to 1.
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