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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.


18h
comment Finding the ACVF
The ACVF of Z itself is causing you problems? Wow.
22h
awarded  Revival
1d
comment Causaulity in AR(2) process
Now we have a definition! So... who are the $\psi_j$ in your case? (Your comment makes no sense after "So for my question" so I am keeping only the part that makes sense, sorry.)
1d
comment Lyapunov exponent for simple functions
@Phonon ?? Anything not zero.
1d
answered What is acceptable set of values $E[ \max(X-4,0)]$?
1d
comment Inequality with infimum and supremum for $A \subseteq \bigcup_{n=1}^{\infty}A_n$
Got something from the answer below?
1d
comment Uniform convergence of $\ln \left(e^x + \frac{1}{n} \right)$
Got something from the answer below?
1d
answered Variance of stochastic process $MA(2)$
1d
comment conditional expectation of two independent normal random variable
Just for the record, the formula $E[X|Y] = \frac{1}{P(Y)} \int_Y XdP$ is absurd.
1d
comment Find conditional probability $\mathbb{P}(X \le x | \max(X,Y)) $
Got something from the answer below?
1d
comment Which of the following option is true?
@DanielFischer Right.
1d
comment Which of the following option is true?
Neither 1. nor 2. implies the property.
1d
comment Converting an ODE in polar form
The conversion is not over, you want to express $d\Phi(t)/dt$ as a function of $r(t)$, $\Phi(t)$, and the matrix at time $t$, only, and likewise for $dr(t)/dt$.
1d
comment Prove $x\to 0$ as $t\to \infty$ if we consider the system of equations $x'=(A+B(t))x$ where $B(t)\to 0$ and $A$ has negative eigenvalues.
Explain that every eigenvalue of $A+B(t)$ is $\leqslant-\varepsilon$ for every $t\geqslant t_0$ and proceed.
1d
comment Lyapunov exponent for simple functions
Are you aware that simply the definition implies that the Lyapunov exponent for the $3x$ function is $\log3\gt0$? And a similarly direct computation is available for the cosine case...
1d
comment Causaulity in AR(2) process
Still no definition? So be it.
1d
answered Understanding sigma super additivity
1d
revised Probability Assignment to Intervals in $\mathbb{R}^{n}$.
added 13 characters in body
1d
revised How to solve the recurrence relation for tight asymptotic bound without using master theorem?
deleted 1 character in body
1d
answered Probability Assignment to Intervals in $\mathbb{R}^{n}$.