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Regression Slope $t$-Interval: Dow Jones and Year

APSTAT-ENGLWJ

In February of 2009, the Dow Jones Industrial Average (DJI) reached a low that it hadn't seen in 10 years. Since then, the Dow Jones has been steadily increasing. Analysts have been studying the relationship between the high points of the Dow Jones for each year since 2009. A computer regression analysis of the data is given below:

Dependent variable is: Dow Jones Industrial Average (DJI)
$R^2 = 93.33\%$
$s= 1116.14$, with $6-2= 4$ D.O.F.

Variable Coefficient s.e Coeff t-ratio prob
Constant 8224.89 735.23 16.06 0.00001
Year 1993.35 123.34 7.47 0.0017



Assuming all of the conditions have been satisfied, which of the following gives a $90\%$ confidence interval for the slope of the regression line?

A

$1993.35\pm (1.645)(123.34)$

B

$1993.35\pm (1.943)(123.34)$

C

$1993.35\pm (2.132)(123.34)$

D

$8224.89\pm (1.943)(735.23)$

E

$8224.89\pm (2.132)(735.23)$