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bio website reddit.com/r/…
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visits member for 2 years, 1 month
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when someone smiles at me, all I see is an ape bearing its teethe


Sep
21
comment Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
Are you sure? The wikipedia article doesn't mention it.
Sep
21
revised Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
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Sep
21
comment Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
I don't know about other conditions, I'm basing this off of en.wikipedia.org/wiki/… I guess it says the Hessian must be invertible as well.
Sep
21
comment Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
@JonathanY. I'm having trouble seeing how this shows positive curvature in all directions.
Sep
21
comment Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
You're right, I guess I should have specified for $n\geq 2$.
Sep
21
revised Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
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Sep
21
asked Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
Aug
22
revised Counting the number of additions/subtractions for Gauss-Jordan Elimination
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Aug
22
asked Counting the number of additions/subtractions for Gauss-Jordan Elimination
Aug
18
accepted Question on sufficient statistics
Aug
18
accepted Show that $(x+1+O(x^{-1}))^x = ex^x + O(x^{x-1})$ for $x\rightarrow \infty$
Aug
15
revised Question on sufficient statistics
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Aug
15
asked Question on sufficient statistics
Aug
15
accepted Calculating a probability mass function (sufficient statistic)
Aug
14
comment Calculating a probability mass function (sufficient statistic)
@AlexR. ahh ok, well that would explain my inconsistent results, thanks.
Aug
14
comment Calculating a probability mass function (sufficient statistic)
@AlexR. so you're saying that $T$ is not a random variable taking values in $1,...,n$ depending on which $X_k$ is the smallest, but instead takes the value of $X_{(1)}$?
Aug
14
asked Calculating a probability mass function (sufficient statistic)
Aug
8
comment Help Proving that $\frac{(1+\frac{1}{t})^t}{e} = 1 -\frac{1}{2t} + O(\frac{1}{t^2})$ for $t\geq 1$
Ansturm is now banned.
Jul
22
accepted Sampling 100 widgets to test for defective ones
Jul
21
comment Sampling 100 widgets to test for defective ones
Yah that's right. I believe their reasoning would have been correct if the $P(B_i)$ were uniform for all $i$, but since $P(B_6)$ is very small compared to $i$'s closer to $50$, their reasoning isn't correct.