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As somebody used to say:

Does research. Smokes. Battles administration. Smokes. Wishes he could stop battling administration so that he could have more time to do research. Smokes some more.

The same. Except I do not smoke.


How to ask a good question?

This paragraph is for my personal use but freely available:

Welcome to Math.SE! Please, consider updating your question to include what you have tried and where you are getting stuck. That way, people on this site will know exactly what help you need.


1d
revised What is “subordination” with respect to stochastic processes?
deleted 12 characters in body
1d
comment Suppose that X1 and X2 denote a random sample of size 2 from a gamma distribution, Xi~GAM(2,1/2). Find the pdf of Y=sqrt(X1+X2)
This is all you did? Write down the gamma(2,1/2) density? And what about starting to solve the exercise?
1d
comment Faster way to for $z^3 = -2 (1+i \sqrt 3) \bar z$ than complex algebra
Writing $z$ in polar form and using $1+i \sqrt3=2\exp(i\pi/3)$ yields a one-line proof, no?
1d
comment A random sample of size 5 is drawn from the pdf $f_{Y}(y) = 2y, 0\leq y \leq 1$. Calculate $P(Y_{(1)} < 0.6 < Y_{(5)})$.
((Comment by the OP now deleted.))
1d
comment Convergence of $a_n$ given $\limsup\frac{\log{a_n}}{\log{n}}$
No indeed, but one could expect that after a while, one is aware of, and stops disregarding, the rules of the site.
1d
comment Suppose that X1 and X2 denote a random sample of size 2 from a gamma distribution, Xi~GAM(2,1/2). Find the pdf of Y=sqrt(X1+X2)
"If you know what the Gamma Distribution is then it is not hard to see what I did" Wrong. This is the whole point, one cannot know what you did. Change your keyboard if really this is necessary (which I doubt) and start following the rules of the site.
1d
comment Let $X$ and $Y$ have joint pdf $f(x,y)= 4e^{-2(x+y)}$; $0<x<\infty$, $0<y<\infty$. Find the CDF of $W=X+Y$
Yeah, and I suggested to consider (X,W). A pair. Oh, whatever.
1d
comment Lebesgue integration of $f(x)=\frac{1}{x}$ where $x\in[0,3]$
Two different limits for the same quantity? Hmmm...
1d
comment Convergence of $a_n$ given $\limsup\frac{\log{a_n}}{\log{n}}$
1 year on the site and 30+ questions asked and you post... this?
1d
comment Suppose that X1 and X2 denote a random sample of size 2 from a gamma distribution, Xi~GAM(2,1/2). Find the pdf of Y=sqrt(X1+X2)
Show what you actually did, at present it is impossible to say.
1d
comment Let $X$ and $Y$ have joint pdf $f(x,y)= 4e^{-2(x+y)}$; $0<x<\infty$, $0<y<\infty$. Find the CDF of $W=X+Y$
Sorry but you are not making much sense. 3 variables? Huh...
1d
revised How to prove $n < \left(1+\frac{1}{\sqrt{n}}\right)^n$
added 4 characters in body
1d
comment How to prove $n < \left(1+\frac{1}{\sqrt{n}}\right)^n$
"Hint"?? $ $ $ $
2d
comment A random sample of size 5 is drawn from the pdf $f_{Y}(y) = 2y, 0\leq y \leq 1$. Calculate $P(Y_{(1)} < 0.6 < Y_{(5)})$.
Are you seriously thinking that the event only depends on Y1 and Y2 or what?
2d
comment Let $X$ and $Y$ have joint pdf $f(x,y)= 4e^{-2(x+y)}$; $0<x<\infty$, $0<y<\infty$. Find the CDF of $W=X+Y$
And what is preventing you from using the same approach here, say to (X,W), then to deduce the distribution of W?
2d
comment Conditional expectation for random walks
Indeed, Sn/n. Well done.
2d
answered Expectation of a random variable that is similar to standard deviation distribution
2d
comment A random sample of size 5 is drawn from the pdf $f_{Y}(y) = 2y, 0\leq y \leq 1$. Calculate $P(Y_{(1)} < 0.6 < Y_{(5)})$.
Where is your attempt to follow the hint?
2d
answered Conditional expectation for random walks
2d
comment Conditional expectation for random walks
No E[X11S−1n[B]]/P[S−1n(B)] is E(X1|Sn$\in$B), which is not a constant for every set B in the Borel sigma algebra (not the sigma-algebra generated by Sn). // Right, E(X1|Sn)=E(Xi|Sn) for every i. What happens when you sum this over i?