shirobia
shirobia
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October 9th, 2011 at 12:00:51 AM permalink
Q1 Let (X_n) for n>0 be a Galton-Watson branching process starting with one particle (that is, X_0 = 1) and o ffspring distribution

p0 = 1/6 ; p1 = 1/3 ; p2 = 1/3 ; p3 = 1/6 ;

(A) P[lim n->infinity, X_n = 0] > 0
(B) P[lim n->infinity, Xn = infinity] > 0
(C) EX_n < EX_n-1
(D) P[Popul. ever dies out] = 0.5*sqrt(13) - (3/2)
(E) E(X_10) approx= 62:125
(F) Var(X_10) approx= 128.831...



Q2 Let (X_n), for n>0 be a Galton-Watson branching process starting with one particle (that is, X_0 = 1) and o ffspring distribution

p_k =(lamda^k)*exp(-lamda)/ (k!) ; k >= 0; 0 < k < 1;

(A) P[lim n->infinity, X_n = 0] < 1
(B) P[lim n->infinity, Xn = infinity] = 0
(C) EX_n < EX_n-1
(D) 0 is transient
(E) E(Xn) = lamda^n
(F) Var(Xn) = (lamda^n)*(sigma^2)


Thank you soo much!
Wizard
Administrator
Wizard
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October 9th, 2011 at 12:45:22 AM permalink
We certainly get the gamut of questions here, from cheating boyfriends to Galton-Watson branching processes. To be honest with you, I don't know what that is. Hopefully ME or CM can be of more help.
"My life is spent in one long effort to escape from the commonplace of existence. These little problems help me to do so." -- Sherlock Holmes
CrystalMath
CrystalMath
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October 9th, 2011 at 7:31:27 AM permalink
Is this True/False or do you pick an answer A to F? Some of the statements in A-F are clearly wrong given the info stated in Q1.
I heart Crystal Math.
buzzpaff
buzzpaff
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October 9th, 2011 at 8:25:42 AM permalink
The Galton–Watson process is a branching stochastic process arising from Francis Galton's statistical investigation of the extinction of family names.
shirobia
shirobia
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October 9th, 2011 at 10:13:37 AM permalink
Quote: CrystalMath

Is this True/False or do you pick an answer A to F? Some of the statements in A-F are clearly wrong given the info stated in Q1.



pick an answer from A to F
CrystalMath
CrystalMath
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October 9th, 2011 at 5:17:25 PM permalink
Q1 Let (X_n) for n>0 be a Galton-Watson branching process starting with one particle (that is, X_0 = 1) and o ffspring distribution

p0 = 1/6 ; p1 = 1/3 ; p2 = 1/3 ; p3 = 1/6 ;

(A) P[lim n->infinity, X_n = 0] > 0
(B) P[lim n->infinity, Xn = infinity] > 0
(C) EX_n < EX_n-1
(D) P[Popul. ever dies out] = 0.5*sqrt(13) - (3/2)
(E) E(X_10) approx= 62:125
(F) Var(X_10) approx= 128.831...

C is false, since EX_n = EX_n-1 * 1.5 .
E is false, since EX_10 = 1.5^10 = 57.665 .

Tell us what you know, and maybe we can help more.
I heart Crystal Math.
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