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I hereby authorize whoever it may concern to post my comments as answers if they wish, whether as community wiki or otherwise if you like imaginary internet points.


Jul
15
comment What is the edge called that converts a tree to a directed acyclic graph?
These correspond to what would be cycles if you interpreted your DAG as an undirected graph. So possibly something related to the phrase undirected cycle?
Jul
14
awarded  Nice Answer
Jul
14
comment Variational Principles: Lagrange Multipliers
Tip: Use \| instead of ||, it looks better: $\|\mathbf x\|$ vs. $||\mathbf x||$.
Jul
14
reviewed Approve suggested edit on Evaluate: $I = \int^{\pi/2}_0 (\sqrt{\sin x}+\sqrt{\cos x})^{-4}dx$
Jul
14
comment Box-Muller method for correlated normals
Is there a reason you are seeking an alternative approach?
Jul
14
comment Apparent Paradox in the Idea of Random Numbers
Related: Probability of picking a random natural number
Jul
14
comment Expressing the probability density function of $Ax$ in terms of the pdf of $x$
Well... the question used to be specifically about scale-invariant probability distributions, not about scaling arbitrary probability distributions in general. See, for example, the link at the end of the post. I'm not convinced that the edited title matches the OP's intent.
Jul
13
comment Metric for movement in 2D space
The average velocity of a particle over some time interval is just (position at end of interval - position at start of interval)/(duration of interval).
Jul
13
comment Is it plausible that multiple rankings can be averaged?
Not really, no. Just given the ranking you can't tell whether the first- and second-ranked advisors in a field are almost equally good or whether the first-ranked advisor is far and away the best and all the rest are uniformly terrible.
Jul
12
revised What exactly is a number?
There's a cleaner way to strike through text; hope you don't mind.
Jul
12
comment Expressing the probability density function of $Ax$ in terms of the pdf of $x$
On further reflection, you are correct and the web page is wrong. The Pareto distribution is a scale invariant probability distribution that satisfies $f(Ax)=kf(x)$ for $k\ne1/A$.
Jul
12
revised MaxMin: how much does the min “see”?
edited body
Jul
12
comment $\lfloor \sqrt{\lceil x \rceil} \rfloor = \lfloor \sqrt{x} \rfloor, \forall x \in \mathbb{R}$
@Joey: You should try plugging in $x$ into your attempt and see which step fails.
Jul
12
answered draw an Ellipsoid given its quaderatic equation in Matlab
Jul
12
comment Expressing the probability density function of $Ax$ in terms of the pdf of $x$
$Af(Ax)=f(x)$ is a property of scale-invariant probability distribution functions. If it is not true for your $f$, that just means that your $f$ is not scale-invariant.
Jul
12
comment My data is not normally distributed: what can I do to estimate a tail probability?
This question might be a better fit for stats.stackexchange.com .
Jul
11
answered MaxMin: how much does the min “see”?
Jul
11
comment MaxMin: how much does the min “see”?
@Adam: It's perfectly well defined; see Taladris's answer. In the inner expression $\min\limits_b ab$, the $a$ is a free variable. All that means is that the value of $\min\limits_b ab$ depends on the value of $a$.
Jul
11
comment Need help with optimization concepts.
Yes, you have to include multipliers for all constraints, including non-negativity constraints. Otherwise, for example, you would not be able to find the minimum of $(x-1)^2+(y+1)^2$ subject to $x\ge0$, $y\ge0$.
Jul
10
comment How can I find the square root using pen and paper?
possible duplicate of Is there any simple method to calculate $\sqrt x$ without using logarithm