Consider the following very simple random walk model. Let the starting position Xo = 0 be deterministic. At each time t yo flip a fair coin and add 1 to X,-1 if you see heads H, else add oif you see tails T. Suppose the first 9 coin fips result in the sequence HTTTHHTTT. Compute the first 10 terms of the time series {X,} Find the expected position E [X10] at time t = 10. 3.5 Find the expected position E [X20] at time t = 20. 8.5 Find the variance of the position X10 at time t = 10. 0.25 Find the variance of the position X20 at time t = 20. 0.25

Consider the following very simple random walk model. Let the starting position Xo = 0 be deterministic. At each time t yo flip a fair coin and add 1 to X,-1 if you see heads H, else add oif you see tails T. Suppose the first 9 coin fips result in the sequence HTTTHHTTT. Compute the first 10 terms of the time series {X,} Find the expected position E [X10] at time t = 10. 3.5 Find the expected position E [X20] at time t = 20. 8.5 Find the variance of the position X10 at time t = 10. 0.25 Find the variance of the position X20 at time t = 20. 0.25

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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