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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.


Jun
14
revised How can $\left({1\over1}-{1\over2}\right)+\left({1\over3}-{1\over4}\right)+\cdots+\left({1\over2n-1}-{1\over2n}\right)+\cdots=0$?
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Jun
14
comment How can $\left({1\over1}-{1\over2}\right)+\left({1\over3}-{1\over4}\right)+\cdots+\left({1\over2n-1}-{1\over2n}\right)+\cdots=0$?
@JonasMeyer Yes.
Jun
14
answered How can $\left({1\over1}-{1\over2}\right)+\left({1\over3}-{1\over4}\right)+\cdots+\left({1\over2n-1}-{1\over2n}\right)+\cdots=0$?
Jun
14
comment Maximum Likelihood Estimator
Exercise: adapt these considerations to the simpler previous question.
Jun
14
answered Maximum Likelihood Estimator
Jun
14
revised Estimate the scale of $e^{-(m+1) t} \sum _{k=0}^{\infty } \frac{t^k}{k!}\left(\sum _{r=0}^k \frac{t^r}{r!}\right)^{m}$
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Jun
14
revised Is $f(x)=o(x^\alpha)$ for every $\alpha\gt0$ enough to know that $\int_c^x dt/f(t) \sim x/f(x)$?
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Jun
14
revised How to solve this stochastic integrals?
edited body
Jun
14
comment why is this Markov Chain aperiodic
I fail to understand this answer. The state (1,0) is not stationary and no state "dies out". doniyor: can you explain what you understood?
Jun
14
answered why is this Markov Chain aperiodic
Jun
14
answered Brownian motion or not?
Jun
14
comment Sum of 2 Brownian motions
"The sum of (jointly) stationary processes is stationary" is true but slightly misleading since it does not apply to the present case.
Jun
14
comment why $g_n$ is measurable in the proof of Fatou's Lemma
The assumption that $g$ is measurable is implicit but very much necessary here.
Jun
14
comment Differential equation, perturbation method
Are you asked to prove that $y_0(x)=\frac12x^2$ and, for every $\epsilon\gt0$, $y_\epsilon(x)\gt y_0(x)$ for $x\gt0$ and $y_\epsilon(x)\lt y_0(x)$ for $x\lt0$?
Jun
14
comment Proving there are no integer solutions for $3x^2=9+y^3$
In the "alternative proof", the implication $3^2\mid x^2-3\implies 3^2\mid x^2$ is dubious since $3^2$ is not a divisor of $3$. The "initial proof" is correct.
Jun
13
revised Continued fraction fallacy: $1=2$
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Jun
13
revised Finding $\lim\limits_{n \to \infty} \sum\limits_{k=0}^n { n \choose k}^{-1}$
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Jun
13
answered What does $\lim \limits_{n\rightarrow \infty }\sum \limits_{k=0}^{n} {n \choose k}^{-1}$ converge to (if it converges)?
Jun
13
comment $X,Y$ i.i.d., $X$ and $(X+Y)/\sqrt{2}$ have the same dist., then show that $X$ has a normal distribution
One does not assume that $X$, $Y$ and $(X+Y)/\sqrt2$ are i.i.d., only that $X$ and $Y$ are.
Jun
13
comment Absolute and conditional convergence of $\sum_{n=1}^\infty\frac{n(x-1)^n}{2^n(3n-1)}$ and $\sum_{n=1}^\infty\frac{1}{2n -1}(\frac{x+2}{x-1})^n$
Tip for a): Determine the radius of convergence of the series $\sum\limits_n\frac{n}{3n-1}z^n$. Tip for b): Determine the radius of convergence of the series $\sum\limits_n\frac1{2n-1}z^n$.