In: Statistics and Probability
The following table shows the number of full-time faculty that WVU has on staff throughout the years.
Year | # of Faculty | |
2003 | 1230 | |
2007 | 1300 | |
2009 | 1440 | |
2013 | 1470 | |
2017 | 1530 | |
2018 | 1630 |
(A) Find the equation of the regression line that represents the
number of full-time faculty, F , as a function of
x years since 2000. (round the regression coefficients to
two decimal places)
F(x) =
(B) What is the correlation coefficient (r-value) for the
regression model? (Round your answer to three decimal places)
r =
(C) Given the value of r , does the regression line model
the data well? That is, does the equation do a good job of modeling
the data?
Yes, the r-value is low, meaning the data can be modeled using a line
No, the r-value is high, meaning the data can't be modeled using a line
Yes, the r-value is high, meaning the data can be modeled using a line
No, the r-value is low, meaning the data can't be modeled using a line
(D) Using the regression line, How many Faculty members did WVU
have in 2010? (Round your answer to the nearest whole number)
(A)
From the given data, the following Table is calculated:
X | F | XF | X2 |
3 | 1230 | 3690 | 9 |
7 | 1300 | 9100 | 49 |
9 | 1440 | 12960 | 81 |
13 | 1470 | 19110 | 169 |
17 | 1530 | 26010 | 289 |
18 | 1630 | 29340 | 324 |
Total = 67 | 8600 | 100210 | 921 |
the equation of the regression line that represents the number of full-time faculty, F , as a function of x years since 2000 is given by:
F(X) = 1163.48 + 24.17 x
(B)
From the given data, the following Table is calculated:
X | F | XF | X2 | Y2 |
3 | 1230 | 3690 | 9 | 1512900 |
7 | 1300 | 9100 | 49 | 1690000 |
9 | 1440 | 12960 | 81 | 2073600 |
13 | 1470 | 19110 | 169 | 2160900 |
17 | 1530 | 26010 | 289 | 2340900 |
18 | 1630 | 29340 | 324 | 2656900 |
Total = 67 | 8600 | 100210 | 921 | 12435200 |
The correlation coefficient (r-value) for the regression model = 0.964
(C) Correct option:
Yes, the r-value is high, meaning the data can be modeled using a line