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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.


Oct
4
comment Recurrence of a certain class of $2$-$d$ random walks
One can make independent the displacements of each coordinate (which are, as you note in a comment below, very much dependent in the original model) if one passes in continuous time, using Poisson processes and splitting them. Then the explanation of the recurrence of your models becomes that the integral of $1/\sqrt{t}\cdot1/\sqrt{t}=1/t$ diverges at infinity. Is this the kind of thing you are after?
Oct
4
comment What does different conditional mean
One can define $E[X|Y=y]$ as $f(y)$ only when $f(y)$ is nonambiguous, that is, if and only if $P[Y=y]\ne0$. Otherwise, $f(y)$ can be anything.
Oct
4
comment Markov chains for beginners, how to think about them?
The identities $p(y)=p(y\mid x)p(x)$ and $p(z)=p(z\mid y)p(y)$ are nearly always wrong, Markov chain or not.
Oct
4
answered A limit problem $0\log \cfrac{0}{0}=0$
Oct
4
comment What does different conditional mean
@Mrclause No, E[X|Y=y] is a number, just like E[X]. Would you say one gets a new "result" E[X] each time one does a new experiment?
Oct
4
comment normal approximation to binomial and poisson
"when I searched for these approximations there were different conditions used" Which conditions?
Oct
4
answered Markov chains for beginners, how to think about them?
Oct
4
comment Checking proof that a given process is a martingale
The assertion that "x→exp(λx)∈L1(P)" is absurd since "x→exp(λx)" is defined on the real line while P is a measure on Ω.
Oct
4
comment What does different conditional mean
@JonathanY. Sure it is, and as such it should be eliminated.
Oct
4
answered What does different conditional mean
Oct
4
revised Random process, stochastic process explained intuitively?
added 111 characters in body
Oct
4
answered Random process, stochastic process explained intuitively?
Oct
4
comment Check whether $\sum\limits_{n=1}^{\infty}\frac{z^n}{(1-z^n)^k}=\sum\limits_{n=1}^{\infty}\sigma_{k-1}(n)z^n$
Look, I do not know which answer is better and why I should give you a criterion and why you ask me this... But, as I said, to accept an answer dealing with the cases $k=1$ and $k=2$ is in contradiction with asking a question about every $k\geqslant1$ case (especially when $k=1$ and $k=2$ are the only cases such that the proposed formula holds!). Note that user @Artin has always been very clear about what was in their answer.
Oct
4
answered Relation between Beta and Gamma distributions
Oct
4
comment Probability of Runs of Heads of Length N
@Henry Congratulations. This does not allow you to air unsubstantiated slur on others' actions, especially when every fact you summon to justify the slur proves irrelevant or even wrong.
Oct
4
comment How many events if the probability of an event is given
@Dilawar Precisely, finding the probabilities would be a mess without independence but finding the expected number of events is quite different, expectation being linear. If each event from a collection of $N$ has probability $p$, then the expected number of events happening is $Np$, irrespectively of their stochastic relations.
Oct
4
comment Probability of Runs of Heads of Length N
@Henry: Thanks for answering, unfortunately I am not convinced to vote for reopening. "Communication", lack thererof: yes, and this supports the closure (15+ comments, real question still unknown, EVEN AFTER YOU POSTED YOUR COMMENTS, wow...). Not the same question: really? You mention FIVE different questions, which may be or may not be the question. How do you know this is not the same question? "Closure 10 seconds before": irrelevant (and rather bizarre, I must say). Note: check the way the site is functioning, you will see that I close nothing.
Oct
4
comment Asymptotic stability of Continuous Time Markov Chains (CTMCs)
Routh-Hurwitz theorem assumes no roots on the imaginary line, hence A violates nothing, it seems.
Oct
4
comment Probability of Runs of Heads of Length N
@Henry Could you elaborate on the reasons why you see this closure as "unfortunate"?
Oct
3
comment Probability of Runs of Heads of Length N
Sorry but I understand nothing from this conversation--hence indeed, it is probably better to stop it. Good luck to you in your inquiries.