Recent content by Absolut

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    So on average, there is 1 television set in the shop?

    Ok, thanks for the advice. Any ideas on what formulas I should be using?
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    So on average, there is 1 television set in the shop?

    Homework Statement A repairman fixes broken televisions. The repair time is exponentially distributed with a mean of 20 minutes. Broken television sets arrive at his shop according to a Poisson process with arrival rate 12 sets per working day. (8 hours). (i) What is the fraction of time that...
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    The multiplication by 2 was "accidental", I got mixed up with another similar question I was doing.
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    I've been trying to do the calculations in my head, so it's a little tricky for me to get the matrix straight...
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    \left(\begin{array}{cccc}0&0.5&1.0&0\\0.85&0&0&0\\0&0.8&0&0\\0&0&0.5&0\end{array}\right) * \left(\begin{array}{cc}3\\2\\2\\0\end{array}\right) = P(1) \left(\begin{array}{cccc}0&0.5&1.0&0\\0.85&0&0&0\\0&0.8&0&0\\0&0&0.5&0\end{array}\right) * P(1) = P(2)...
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    Well, I'm trying to find a value for A(P(t)) - A is the matrix that I found at the very begining, so I was thinking I should be subbing in the birth and death rates into that matrix to find P(t)/P(t+1)?
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    P(t+1) = AP(t) P(t+1) = \left(\begin{array}{cccc}o&b_1&b_2&0\\1-d_0&0&0&0\\0&1-d_1&0&0\\0&0&1-d_2&0\end{array}\right) * P(t)
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    I'd imagine I start off by subbing the values into the given matrix: \ P = \left(\begin{array}{cc}P_0 \\P_1\\P_2\\P_3\end{array}\right) = \left(\begin{array}{cc}3\\2\\2\\0\end{arra y}\right) I also have P(t + 1) = AP(t). So maybe sub in values for t = 0, 1 and 2 (but sub them into...
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    That's actually part of the next question, which I've only just seen: Consider the evolution of the species over the next three years, where the initial population is P_0 = 3, P_1 = 2, P_2 = 2, P_3 = 0. Using the following birth and death rates: d_0 = 0.15, b_1 = 0.5, d_1 = 0.2 b_2 =...
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    My head is fried... sorry for all the obvious questions! f(1) is negative, f(2) is positive... so somewhere in between there is an f(x) that is equal to zero. I was concentrating on the magnitude instead of the signs! Thanks for your help.
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    I only spotted my mistake when I took the time to type it all out in latex code - and it was a small mistake with mixing up a zero in a place where it shouldn't have been! So I did manage to get out my eigenvalue equation, but now I am stuck on another section: If d_0 = 0.15, d_1 = 0.2, d_2...
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    Ok, so here's my full work on finding the determinant so far: \left(\begin{array}{cccc}-\lambda&b_1&b_2&0\\1-d_0&-\lambda&0&0\\0&1-d_1&-\lambda&0\\0&0&1-d_2&-\lambda\end{array}\right) -\lambda \left(\begin{array}{ccc}-\lambda&0&0\\1-d_1&-\lambda&0\\0&1-d_2&-\lambda\end{array}\right)...
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    How Do We Model Population Growth with Age-Specific Birth and Death Rates?

    \left(\begin{array}{cccc}-\lambda&b_1&b_2&0\\1-d_0&-\lambda&0&0\\0&1-d_1&-\lambda&0\\0&0&1-d_2&-\lambda\end{array}\right) That's the (A-\lambdaI) matrix that I'm using Then I'm trying to find the determinant by taking each element of the first row as follows: -\lambda...
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