Recent content by Mike.B

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    Graduate The limit of random variable is not defined

    Define ##B=\{\omega\in \Omega:V(\omega)=\infty\}##? And show ##A\cap B##=0$?
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    Graduate The limit of random variable is not defined

    I have difficulty about combining the final results, is there any inequality involved?
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    Graduate The limit of random variable is not defined

    What is the relation between almost surely and in probability? How to use here?
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    Graduate The limit of random variable is not defined

    Let ##X_i## are i.i.d. and take -1 and +1 with probability 1/2 each. How to prove ##\lim_{n\rightarrow\infty}{\sum_{i=1}^{n}{X_i} }##does not exsits (even infinite limit) almost surely. My work: I use cauchy sequence to prove it does not converge to a real number. But I do not how to prove it...
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    Graduate Structure of generated sigma algbra

    I am think what is the structure of generated ##\sigma##-algebra. Let me make it specific. How to represent ##\sigma(\mathscr{A})##, where ##\mathscr{A}## is an algebra. Can I use the elements of ##\mathscr{A}## to represent the element in ##\sigma(\mathscr{A})##?
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    Graduate Extension of measure on sigma-algebra

    Suppose ##\mu:\mathcal{F}\rightarrow[0,\infty)## be a countable additive measure on a ##\sigma##-algebra ##\mathcal{F}## over a set ##\Omega##. Take any ##E\subseteq \Omega##. Let ##\mathcal{F}_{E}:=\sigma(\mathcal{F}\cup\{E\})##. Then, PROVE there is a countable additive measure...