Model%20Building

Model%20Building - CHAPTER17 ModelBuilding...

This preview shows pages 1–5. Sign up to view the full content.

Click to edit Master subtitle style 4/24/11 CHAPTER 17 Model Building

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
4/24/11 Polynomial Models with One Quantitative  Predictor Variable Simple linear regression equation: Equation for second-order polynomial model: Equation for third-order polynomial model: Equation for general polynomial model: x b b y 1 0 ˆ + = 2 2 1 0 ˆ x b x b b y + + = 3 3 2 2 1 0 ˆ x b x b x b b y + + + = p p x b x b x b x b b y + + + + + = ... ˆ 3 3 2 2 1 0
4/24/11 Example with One Quantitative Predictor  Problem 17.8:  International Data Corporation has reported the  following costs per gigabyte of hard drive storage space for years 1995  through 2000. Using  = 1 through 6 to represent years 1995 through  2000, fit a second-order polynomial model to the data and estimate the  cost per gigabyte for the year 2008.    The regression equation     will have the form: Year x  = Yr = Cost 1995 1 \$261.84 1996 2 137.94 1997 3 69.68 1998 4 29.30 1999 5 13.09 2000 6 6.46 2 2 1 0 ˆ x b x b b y + + =

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Example, Problem 17.8, cont. Using Excel Output SUMMARY OUTPUT Regression Statistics Multiple R 0.99655892 R Square 0.99312969 Adjusted R Square 0.98854948 Standard Error 10.5650522 Observations 6 ANOVA df SS MS F Significance F Regression 2 48405.43097 24202.7155 216.830715 0.00056946 Residual 3 334.8609836 111.620328 Total 5 48740.29195 Coefficients Standard Error t Stat P-value Lower 95% Upper 95% Intercept 387.993 18.89933991 20.5294472 0.00025272 327.846809 448.139191 yearcode -147.65675 12.3644646 -11.9420254 0.00126294 -187.006032 -108.307468
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 15

Model%20Building - CHAPTER17 ModelBuilding...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online