Recent content by oyth94

  1. O

    MHB Applying the central limit theorem

    Suppose the time in days until a component fails has the gamma distribution with alpha = 5, and theta = 1/10. When a component fails, it is immediately replaced by a new component. Use the central limit theorem to estimate the probability that 40 components will together be sufficient to last at...
  2. O

    MHB Converging almost surely proof

    How do I prove that given Xn converges almost surely to X, that f(Xn) will converge almost surely to f(X)?
  3. O

    MHB Moment generating function question

    Re: moment generating function question I'm not sure how you arrived at this answer..can you please explain?
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    MHB Conditional expectation proof question

    Here is a proof question: For two random variables X and Y, we can define E(X|Y) to be the function of Y that satisfies E(Xg(X)) = E(E(X|Y)g(Y)) for any function g. Using this definition show that E(X1 + X2|Y) = E(X1|Y) + E(X2|Y) So what I did was I plugged into X = X1 + X2 E(E(X1 +...
  5. O

    MHB Generating Function for Gambler's Probs of Broke at Time n

    Is there any other way to solve it besides using Catalan number and recursive relation and gamblers ruin?? Like using expected value or different distributions of some sort?
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    MHB Components working at a particular time

    Hello .Sorry for all the questions I am asking...but I have another one I would like to seek help for.: Suppose a system has 10 components and that a particular time the jth component is working with probability 1/j for j= 1,2,...10. How many components do you expect to be working at that...
  7. O

    MHB Expected number of light bulbs on

    Thank you so much! I arrived with the same answer but I used either Poisson or Binomial. But my approach I didn't involve expected value...which I should...
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    MHB Moment generating function question

    Let X1,X2,…,Xn be independent random variables that all have the same distribution, let N be an independent non-negative integer valued random variable, and let SN:=X1+X2+⋯+XN. Find an expression for the moment generating function of SN so all i know is that it is i.i.d but i am not sure what...
  9. O

    MHB Expected number of light bulbs on

    There are 50 light bulbs in a room each with its own switch. If a light bulb is on, Dick turns it off and if it is off , he turns it on. Initially all light bulbs are off . After 50 flips and assuming that Dick chooses switches to be flipped randomly, what is the expected number of light bulbs...
  10. O

    MHB Generating Function for Gambler's Probs of Broke at Time n

    Suppose a gambler starts with one dollar and plays a game in which he or she wins one dollar with probability p and loses one dollar with probability 1 - p. Let fn be the probability that he or she fi rst becomes broke at time n for n = 0, 1, 2... Find a generating function for these...
  11. O

    MHB Finding expected value from the moment generating function

    okay so i forgot to mention i have to take the derivative after i factor/cancel out the t right. so then it becomes 1 + t/2! + t^2 /3! + ... derivative --> 1/2 + 2t/6 + ... and then after i take the derivative i set t=0 because mx1(0) = EX so from there i will get EX = 1/2 as you said before.
  12. O

    MHB Finding expected value from the moment generating function

    Thank you for your help. For how I did it was I used the series expansion for e^t which is the summation of (t)^k / k! so $$[(t^k / t!) - 1 ] / t$$ = [(1 + t/1 + t^2 / 2! + t^3 / 3! + ...) - 1] / t then the 1s cancel out and I can factor out the t so it becomes = 1 + t/2! + t^2 / 3! + ... so...
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    MHB Finding expected value from the moment generating function

    Suppose I have the MGF moment generating function mx(t) = (e^t -1)/t How can I find EX?
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    MHB Can E(Z) be determined from E(X) and E(Y) when X and Y are independent?

    Hi I know this may be a silly question but i am doubting myself on how i did this question: Suppose X and Y are independent, with E(X) = 5 and E(Y) = 6. For each of the following variables Z, either compute E(Z) or explain why we cannot determine E(Z) from the available information: Z =...
  15. O

    MHB Expected values: three fair coins

    Re: expected values: three fair coins Oh I see what you did! Thank you so much!
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