In: Statistics and Probability
The Centers for Disease Control and Prevention Office on Smoking and Health (OSH) is the lead federal agency responsible for comprehensive tobacco prevention and control. OSH was established in 1965 to reduce the death and disease caused by tobacco use and exposure to secondhand smoke. One of the many responsibilities of the OSH is to collect data on tobacco use. The following data show the percentage of U.S. adults who were users of tobacco for a recent 11-year period
Year | Percentage of Adults Who Smoke |
1 | 22.7 |
2 | 21.9 |
3 | 21.2 |
4 | 20.8 |
5 | 20.8 |
6 | 20.2 |
7 | 19.3 |
8 | 20.6 |
9 | 20.6 |
10 | 19.8 |
11 | 18.9 |
(a)y-intercept, b0=22.4146
slope, b1=-0.2827
MSE=0.3471
(b) here slope=-0.2827, which change in dependent variable when unit change is done in independent variable.
so each year there will decrease in smoking by 0.2827%
so in 9 years there would decrease =9*0.2827=2.5443%, so regression model from part (b) does not suggest that OSH is on target to meet this goal
required number of years=12/0.2827=42.4877 ( required number of 42 years, nearest whole number)
Regression Statistics | ||||||
Multiple R | 0.858998 | |||||
R Square | 0.737878 | |||||
Adjusted R Square | 0.708753 | |||||
Standard Error | 0.589118 | |||||
Observations | 11 | |||||
ANOVA | ||||||
df | SS | MS | F | Significance F | ||
Regression | 1 | 8.792818 | 8.792818 | 25.33511 | 0.000706 | |
Residual | 9 | 3.123545 | 0.347061 | |||
Total | 10 | 11.91636 | ||||
Coefficients | Standard Error | t Stat | P-value | Lower 95% | Upper 95% | |
Intercept | 22.31455 | 0.380965 | 58.57372 | 6.21E-13 | 21.45274 | 23.17635 |
X Variable 1 | -0.28273 | 0.05617 | -5.0334 | 0.000706 | -0.40979 | -0.15566 |