Explore BrainMass
Share

Explore BrainMass

    Probability - Conditional Distribution

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    A pollster wishes to obtain information on intended voting behavior in a two party system and samples a fixed number (n) of voters. Let X_1 ..., X_n denote the sequence of independent Bernoulli random variables representing voting intention, where E(X_l) = p, i = 1, ..., n

    (a) Suppose the number of voters n is fixed, compute E(X) and Var(X)

    (b) Suppose the number of voters N is a random variable, with P(N=n)=p_n

    (i) Find the conditional distribution of X given N
    (ii) Find the conditional expectation E(X|N) and conditional variance Var(X|N)

    (c) Express Var(X) in terms of p, E(N), and Var(N), by using the law of total variance.

    © BrainMass Inc. brainmass.com October 10, 2019, 5:59 am ad1c9bdddf
    https://brainmass.com/math/probability/probability-conditional-distribution-law-total-variance-523839

    Attachments

    Solution Preview

    ** Please see the attached file for the complete solution **

    (a) Since the ...

    Solution Summary

    This solution includes a detailed explanation of the law of total variance formula and conditional expectations by using this problem as an illustrative example. The step-by-step explanation in this solution provides a clear application of conditional expectation and variance formulas in a concrete setting.

    $2.19