expected value

  1. A

    Expected Value - Help PLEASE!!!

    How do you find E(1/X)? X is distributed binomially with probability p and n+1 terms: X~Binom(n+1, p). So E(X) = p(n+1), but how do I find E(1/X)? Any help is much appreciated, thank you!
  2. S

    [Mathematica] ANY help would be appreciated

    Hi guys, I am very frustrated, mainly because my knowledge of Mathematica is abysmally low. I want to calculate the expected value of ln(x), where X is gamma(a,b) distributed, but it would seem that my Mathematica is bi-polar. I don't need the whole derivation, I only need the final...
  3. H

    Question about normally distributed estimator with a constant

    Hi all i'm having serious difficulties with the following problem :shakehead any help would be much appreciated. _________________________________________________ Assume that some random variable x is normally distributed with mean μ and variance σ². consider the following estimator where ci...
  4. B

    Conditional expectation

    Good afternoon, I have to calculate the expected value of a logistic distribution given that the values are above a given constant (lets say 0). So far I have done it numerically by programming a generator of random numbers coming from a logistic distribution and then taking the average of those...
  5. H

    Expected value

    Could someone please explain the following? A guy and a girl play a game where they roll a dice. If the guy rolls an even number, the girl pays him that amount. If he rolls an odd number he pays her that amount. The expected value is supposedly $0.5. ie mean of -1+2-3+4-5+6 but if i...
  6. D

    Expected Value of Order Statistics from Standard Normal Distribution

    Question: Find the expected value of the largest order statistic in a random sample of size 4 from the standard normal distribution. Remarks: I got the only answer to this question without any derivation or proof. The definite integral is very difficult, please help with the integral. Please...
  7. J

    Working with a distribution of outcomes from discrete events

    Hello, I have a data series that result from a long (2,950) series of discrete events. Roughly half of the events ended with a value of exactly -1, the other half are continously distributed between 1 and positive infinity. There are no values between 1 and -1. A histogram would look...
  8. H

    Deriving the Regression Model when E (u | x ) = 1 + + 2x

    Is the question, I'm not sure how to do it. I understand the concept of what its trying to have me prove that u doesn't depend on x, but I don't understand how to solve it. Any help you can give is appreciated. Thanks!