In: Statistics and Probability
x | 42 | 38 | 44 | 25 | 21 | 42 | 35 | 51 | 33 |
y | 21 | 25 | 22 | 28 | 30 | 27 | 21 | 13 | 21 |
1.)Do heavier cars really use more gasoline? Suppose a car is chosen at random. Let x be the weight of the car (in hundreds of pounds), and let y be the miles per gallon (mpg). Write out the least-squares line y=a+bx
2.)Do heavier cars really use more gasoline? Suppose a car is chosen at random. Let x be the weight of the car (in hundreds of pounds), and let y be the miles per gallon (mpg). The estimate y value found in the previous question is _____ (answers are either: an extrapolation, an interpolation, an error, or a residual)
1. y = 38.2620 - 0.4120*x
2. an interpolation
r² | 0.587 | |||||
r | -0.766 | |||||
Std. Error | 3.494 | |||||
n | 9 | |||||
k | 1 | |||||
Dep. Var. | y | |||||
ANOVA table | ||||||
Source | SS | df | MS | F | p-value | |
Regression | 121.4356 | 1 | 121.4356 | 9.95 | .0161 | |
Residual | 85.4533 | 7 | 12.2076 | |||
Total | 206.8889 | 8 | ||||
Regression output | confidence interval | |||||
variables | coefficients | std. error | t (df=7) | p-value | 95% lower | 95% upper |
Intercept | 38.2620 | |||||
x | -0.4120 | 0.1306 | -3.154 | .0161 | -0.7208 | -0.1031 |