1,670 reputation
417
bio website reddit.com/r/…
location meatspace
age
visits member for 2 years, 7 months
seen 2 mins ago

when someone smiles at me, all I see is an ape bearing its teethe


Oct
5
asked Prove that $\frac{d}{dx}\int_0^xf(x,y)dy = f(x,x)+\int_0^x\frac{\partial}{\partial x}f(x,y)dy$
Sep
25
accepted Let $b_n$ decrease monotonically to zero, prove $\sum b_nz^n$ converges for $|z|\leq 1$ and $z\neq 1$
Sep
25
comment Let $b_n$ decrease monotonically to zero, prove $\sum b_nz^n$ converges for $|z|\leq 1$ and $z\neq 1$
@njguliyev oh nice, that does it right there, thanks.
Sep
25
asked Let $b_n$ decrease monotonically to zero, prove $\sum b_nz^n$ converges for $|z|\leq 1$ and $z\neq 1$
Sep
21
comment Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
oh shoot you're right, ok that makes sense.
Sep
21
comment Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
not off the top of my head no, we've just been using this condition without explanation in a numerical optimization class.
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 $a$
added 27 characters in body
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 $a$
added 36 characters in body
Sep
21
asked Prove that if the Hessian of $f$ is positive definite at $a$, then the function attains a minimum at $a$
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
deleted 2 characters in body
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 $X_{(1)}$?