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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.


Apr
2
comment A problem of probability-help please
Somebody decided to turn to MSE to get their homework done and is rapidly posting it on the site by parts.
Apr
2
comment please help for this probability question
Somebody decided to turn to MSE to get their homework done and is rapidly posting it on the site by parts.
Apr
2
comment Upper/lower bound on covariance two dependent random random variables.
Maybe add an argument to show that every value in the interval your answer shows, can be realized.
Apr
2
comment conversion of distribution function
Aaaah... Indeed "something" happens at $\frac12\theta$... Can you compute directly $P(Y=\frac12\theta)$?
Apr
2
comment What's the probability that A wins finally
Which use is the hint (first line)?
Apr
2
comment Probability of explosion in a Markov chain
You are welcome. Why don't you accept the answer below?
Apr
2
revised What does it mean to say “the random variable $X$ conditioned on $X$ being non-negative”?
edited body
Apr
2
comment Interchanging the order of limit and integration
Got something from the answer below?
Apr
2
comment conversion of distribution function
?? You might want to explain what this has to do with the question. No, Y is not of absolutely continuous type.
Apr
2
comment conversion of distribution function
Y is also of absolute continuous type... Why? Please THINK, maths is not about reciting mantras, you know.
Apr
2
comment Types of convergence $X_n \to X$ under which $X$ is independent of $Y$
No doubt you "don't have a counterexample at present", since, if $X_n$ is independent of $Y$ for each $n$ and $X_n\to X$ almost surely, then $X$ is independent of $Y$. To wit, for every bounded continuous functions $u$ and $v$, $E[u(X_n)v(Y)]\to E[u(X)v(Y)]$ by dominated convergence, $E[u(X_n)]\to E[u(X)]$ by dominated convergence, and $E[u(X_n)v(Y)]=E[u(X_n)]E[v(Y)]$ by independence. Thus, $E[u(X)v(Y)]=E[u(X)]E[v(Y)]$, hence the independence.
Apr
2
revised $\sigma$-algebra generated by one-point sets
added 10 characters in body
Apr
2
revised Can we extend any metric space to any larger set?
added 11 characters in body
Apr
2
answered Can we extend any metric space to any larger set?
Apr
2
comment conversion of distribution function
Yes, so $P(X=x)=0$ for every $x$. Now, to $P(Y=y)$, is this always zero as well? What do you think?
Apr
2
answered Question regarding application of Tonelli Theorem
Apr
2
comment Expectation of the maximum of IID geometric random variables
@DaleM If $P(X=k)=p(1-p)^k$ for every $k\geqslant0$, yes.
Apr
1
comment If $f$ is the uniform limit of a bounded sequence on Riemann integrable functions on $[a,b]$, must $f$ be Riemann integrable?
Assume that you ask a basic integration exercise on MSE. Is it better to include in the question your thoughts about the problem? Why?
Apr
1
comment Just a thought… defining “competition”?
Lotka-Volterra.
Apr
1
comment conversion of distribution function
And $P(X=x)=0$ for every $x$ in $[0,\theta]$.