Logistics model in absence of limiting factors

MathBane

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Oct 9, 2009
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The question:

The following table shows the number C, in millions, of basic subscribers to cable TV in the indicated year. These data are from the Statistical Abstract of the United States.

Year | C
1975 | 9.8
1980 | 17.5
1985 | 35.4
1990 | 50.5
1995 | 60.6
2000 | 66.3

(a) Use regression to find a logistic model for these data. (Let t be the time measured in years since 1975. Round the terms to two decimal places and round r to three decimal places.)

\(\displaystyle N = \frac {69.78}{1+7.8e^{-0.194t}}\)

(b) By what annual percentage would you expect the number of cable subscribers to grow in the absence of limiting factors? (Round your answer to one decimal place.)

____ %

(This is where I'm having trouble. What does it mean when it says in the absence of limiting factors? Do I have to rearrange my model?)
 
MathBane said:
The question:

The following table shows the number C, in millions, of basic subscribers to cable TV in the indicated year. These data are from the Statistical Abstract of the United States.

Year | C
1975 | 9.8
1980 | 17.5
1985 | 35.4
1990 | 50.5
1995 | 60.6
2000 | 66.3

(a) Use regression to find a logistic model for these data. (Let t be the time measured in years since 1975. Round the terms to two decimal places and round r to three decimal places.)

\(\displaystyle N = \frac {69.78}{1+7.8e^{-0.194t}}\)

(b) By what annual percentage would you expect the number of cable subscribers to grow in the absence of limiting factors? (Round your answer to one decimal place.)

____ %

(This is where I'm having trouble. What does it mean when it says in the absence of limiting factors? Do I have to rearrange my model?)

Do you know how the logistic model is derived (from ODE)?
 
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