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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.


4h
comment Joint pdf random variables
Because I typed too quickly. Good catch!
4h
comment The joint pdf of random variables $X$ and $Y$
The expectation of a random variable always in (0,1) would be 7? Seems unlikely...
4h
comment Joint pdf random variables
By what exactly?
4h
comment Joint pdf random variables
The minimum: 1/3+y when y<2/3 and 1 when y>2/3.
4h
comment Joint pdf random variables
The upper bound of the integral in x should not be 1/3+y for every y but min(1,1/3+y). Which result do you get with this modification?
5h
comment Joint pdf random variables
Unless you show your workings (instead of describing them), how can we help?
6h
comment Is there a standard proof for $\mathbb P(S^X_n\text{ hits }A\text{ before }B) >\mathbb P(S^Y_n\text{ hits }A\text{ before }B)$?
en.wikipedia.org/wiki/Coupling_%28probability%29
6h
comment What is the derivative of this function: $f(\mathbf{x})=\sum\limits_{k=1}^{n}x_k$ where $\mathbf{x}\in\{0,1\}^n$
$[0,1]^n$ instead of $\{0,1\}^n$, perhaps?
7h
comment Foundation for analysis without axiom of choice?
@RonMaimon Sorry but I must be a little harsh now: you have simply no idea of the domain you pretend to describe (probability theory since the mid 1930s, say)). To say that one "end(s) up introducing filtrations", as if this was a curse, is mere nonsense.
7h
comment A basic question on density function
Actually there is a subtlety here, which is that $\chi_{X(G)}(X)\ne\chi_G$ in general.
8h
comment Counterexamples in set theory
@NiftyKitty95 Except that $|A\cap B\cap C|$ is not $|A\cup B\cup C|-|A|-|B|-|C|$ in general.
8h
comment Foundation for analysis without axiom of choice?
@RonMaimon [Making all the sets measurable will make the probabalists ecstatic, because they operate as if every set is measurable anyway] You formulate many bizarre assertions on this page but this one is not bizarre: it is false (ever heard of a filtration?). And the behaviour you describe just after this sweeping assertion is not even related.
8h
comment Formula needed for calculating probability of recurring events
You are welcome.
8h
comment Proof that a function is measurable
Your "Fubini and Tonelli both" comment (but Tonelli with only one n please) is a mystery to me. What are you trying to say exactly? Anyway, "showing measurability by showing integrability" is quite new, and I certainly did not suggest such an approach (whatever it might mean). Finally, if ever you find the time, please answer my very first question: why not use Fubini?
8h
comment Evaluate $\lim\limits_{x\to\infty}\frac{1}{\sqrt{x}}\int_1^x\ln(1+\frac{1}{\sqrt{t}})dt$
Taylor works. Convexity might be simpler.
12h
comment Correlation between poisson and normal
@JuhoKokkala Yes.
12h
comment Correlation between poisson and normal
Yes, but they were also calling correlation the covariance (this is corrected now). Comment withdrawn. And the Edit in your answer is most welcome, if you ask me... (+1.)
12h
comment A basic question on dostribution of longitude and latitude
Listen, I made a specific suggestion (to read the WP page), did you follow it (instead of starting something else)?
12h
comment A basic question on density function
Now the identity to prove is true. And follows directly from the definition of the distribution of $(X,Y)$. (See, if you thought a little bit more about your questions before posting them, we would not have to go through all this...)
12h
comment Proof that a function is measurable
OK, then forget Tonelli and use Fubini. What else?