In: Statistics and Probability
Student enrollment at a university over the past six years is given below.
Year |
Enrollment |
1 |
6.30 |
2 |
7.70 |
3 |
8.00 |
4 |
8.20 |
5 |
8.80 |
6 |
8.00 |
What is the linear trend expression for the above time series?
Select one:
a. Tt = 6.63 – 0.34t
b. Tt = 6.63t + 0.34
c. Tt = 6.63 + 0.34t
d. Tt = 0.77 + 0.59t
e. Tt = 2.06 + 1.44t
Based on the model you determined in the question above, what is the forecast enrollment for year 10?
Select one:
a. 10.06
b. 66.68
c. 10,062.00
d. 100,062.00
e. 100.6
Solution:
We can use excel to find the least-squares regression equation. The excel output is given below:
SUMMARY OUTPUT | ||||||
Regression Statistics | ||||||
Multiple R | 0.767383067 | |||||
R Square | 0.588876772 | |||||
Adjusted R Square | 0.486095965 | |||||
Standard Error | 0.599205824 | |||||
Observations | 6 | |||||
ANOVA | ||||||
df | SS | MS | F | Significance F | ||
Regression | 1 | 2.057142857 | 2.057142857 | 5.729442971 | 0.074872431 | |
Residual | 4 | 1.436190476 | 0.359047619 | |||
Total | 5 | 3.493333333 | ||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | |
Intercept | 6.633333333 | 0.557830264 | 11.89131133 | 0.000286437 | 5.084548228 | 8.182118439 |
Year (t) | 0.342857143 | 0.143237589 | 2.393625487 | 0.074872431 | -0.054834159 | 0.740548445 |
What is the linear trend expression for the above time series?
Select one:
c. Tt = 6.63 + 0.34t
Based on the model you determined in the question above, what is the forecast enrollment for year 10?
Select one:
a. 10.06