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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.


23h
comment Question about a change of variable used to compute $E(X)$ from the CDF of $X$
I corrected the tags and some inconsiderate uses of $X$ for $x$ in the question.
23h
revised Question about a change of variable used to compute $E(X)$ from the CDF of $X$
deleted 6 characters in body; edited title; edited tags
23h
comment Question about a change of variable used to compute $E(X)$ from the CDF of $X$
You understand why $v=F$ yields $dv=f(x)dx$ but not why $v=1-F$ yields $dv=-f(x)dx$?
1d
revised Prove that if $X \sim N(\mu, \sigma^2)$, then $X \sim \mu + \sigma N(0, 1)$
added 20 characters in body
1d
comment What is $f(x|y<\bar{y})$ equal to?
Where do you see rudeness? Is this a diversion on your part to mask the fact "that you are trying to circumvent the rules of the site by reposting exactly the same question"? Anyway, about the lacks of your question, they are explained in the paragraph: "This question is missing context or other details: Please improve the question by providing additional context, which ideally includes your thoughts on the problem and any attempts you have made to solve it. This information helps others identify where you have difficulties and helps them write answers appropriate to your experience level."
1d
comment Can the transition probabilities of an inhomogeneous Markov chain be written as an exponential?
Indeed, it happens that $$\left.\frac{\mathrm d}{\mathrm dt}\mathrm e^{A+tB}\right|_{t=0}=\sum_{i\geqslant0}\sum_{k\geqslant0}\frac{A^iBA^k}{(i+k+1)‌​!},$$ which is neither $B\mathrm e^A$ not $\mathrm e^AB$ in general (that is, except if $A$ and $B$ commute).
1d
comment Can the transition probabilities of an inhomogeneous Markov chain be written as an exponential?
How do you differentiate $\bar P(s,t)$ exactly?
1d
comment Let $f\in C[0,1]$. Compute $\lim_{t\rightarrow \infty} \frac{1}{t} \log \int_0^1 \cosh(tf(x)) dx$
$\|f\|_\infty$.
1d
revised Expectation of CDF of continuous random variable $X$, evaluated at $X$
deleted 36 characters in body; edited title
1d
answered Asymptotics of sum of binomial distributions
1d
comment Asymptotics of sum of binomial distributions
"under the assumption that $X$, $X^1$ and $X^2$ are independent and identically distributed" No, under the assumption that $X$, $X^1$ and $X^2$ are identically distributed and that $X^1$ and $X^2$ are independent.
1d
comment Expectation related to Normal distribution and its density
Yep, converges iff $\sigma\lt1$. +1.
1d
comment Evaluate $\int_0^1 \sqrt{2x-1} - \sqrt{x}$ $dx$
"without it making the computation any easier" Actually it does since the change of variable $z=2x-1$ shows the second integral is half the first one, and, since a primitive of $\sqrt{x}$ is $\frac23x\sqrt{x}$, one is done.
1d
comment Joint probability of two conditional probabilities
What is the distribution of an event? Are A and B supposed to be events or distributions? All these words are not equivalent... :-)
1d
revised Convergence of the series $\sum\limits_{n\geqslant1}(2-x)(2-x^{1/2})(2-x^{1/3})\cdots(2-x^{1/n})$
deleted 36 characters in body; edited title
1d
revised Convergence of the series $\sum\limits_{n\geqslant1}(2-x)(2-x^{1/2})(2-x^{1/3})\cdots(2-x^{1/n})$
added 527 characters in body
1d
answered Convergence of the series $\sum\limits_{n\geqslant1}(2-x)(2-x^{1/2})(2-x^{1/3})\cdots(2-x^{1/n})$
1d
comment Solving a master equation with linear coefficients
The trouble is that if $P(\ ,\ ,0)$ is singular, every $P(\ ,\ ,t)$ is singular, and then one wonders what the PDE even means.
1d
comment What is meant here with $\omega _k \in A _j=A_{n_k } $
Unclear $\ne$ trivially wrong.
1d
comment Expectation of CDF of continuous random variable $X$, evaluated at $X$
The question should read: "Given the continuous random variable $X$ with cumulative distribution function $F_X$, find $E[F_X(X)]$".