In: Statistics and Probability
Assume that the regression line for the New York City murder rate per 100,000 residents between 2000 and 2010 is given by y=−0.24x+488.7, where x is the year and y is the murder rate. Interpolate to get an approximate value for the rate in 2006. Round your answer to one decimal place.
Interpolated rate
The table below shows the murder rate per 100,000 residents for a large American city over a twelve-year period.
Year |
2000 |
2001 |
2002 |
2003 |
2004 |
2005 |
2006 |
2007 |
2008 |
2009 |
2010 |
2011 |
Rate |
8.8 |
7.1 |
7.2 |
6.8 |
6.4 |
7.1 |
5.8 |
6.1 |
5.4 |
6.2 |
6.1 |
4.9 |
Enter the coefficients of the regression line for this data, rounding each to two decimal places: |
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Slope: |
Intercept: |
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Use your regression line (with rounded coefficients) to estimate this city’s murder rate in 2012. Round your answer to the nearest tenth. |
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Estimate: |
The table below shows per capita cheese consumption, in pounds, for several years for one American state.
Year |
2000 |
2001 |
2002 |
2003 |
2004 |
2006 |
2007 |
2008 |
2009 |
Cheese Consumed |
26.1 |
26.8 |
28.2 |
28.8 |
29.8 |
29.6 |
31 |
30.8 |
32.1 |
Which of the following is the equation of the regression line
for this data?
A. y=−0.595x+1163.4
B. y=1163.4x−0.595
C. y=0.595x−1163.4
D. y=0.595x+1163.4
E. y=1163.4x+0.595
F. y=−0.595x−1163.4
Using the regression line, estimate the per-capita consumption in 2005 to the nearest tenth of a pound. |
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Estimate: |
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Did you just perform interpolation or extrapolation? |
Would you expect the regression line for the price of a camera
vs. the number sold to slope up or down, or would it be
pretty much horizontal?
A. up
B. down
C. horizontal
a) slope= -0.24
intercept = 488.7
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2)
ΣX | ΣY | Σ(x-x̅)² | Σ(y-ȳ)² | Σ(x-x̅)(y-ȳ) | |
total sum | 18040.00 | 263.20 | 82.22 | 31.24 | 48.92 |
mean | 2004.44 | 29.24 | SSxx | SSyy | SSxy |
sample size , n = 9
here, x̅ = Σx / n= 2004.444 ,
ȳ = Σy/n = 29.244
0.0145898
SSxx = Σ(x-x̅)² = 82.2222
SSxy= Σ(x-x̅)(y-ȳ) = 48.9
estimated slope , ß1 = SSxy/SSxx = 48.9
/ 82.222 = 0.59500
intercept, ß0 = y̅-ß1* x̄ =
-1163.40000
so, regression line is Ŷ =
-1163.4000 + 0.5950
*x
C. y=0.595x−1163.4
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Predicted Y at X= 2005
is
Ŷ = -1163.4000 +
0.5950 *2005= 29.6
interpolation
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As the price increases, we would expect the number sold to be
decrease. Hence,
It will be a down slope.
answer: DOWN
please revert for doubts and |
please UPVOTE the solution |