# 420Hw04ans - STAT 420 Homework #4 Fall 2007 2.2 The dataset...

This preview shows pages 1–3. Sign up to view the full content.

STAT 420 Fall 2007 Homework #4 2.2 The dataset uswages is drawn as a sample from the Current Population Survey in 1988. Fit a model with weekly wages as the response and years of education and experience as predictors. Report and give a simple interpretation to the regression coefficient for years of education. Now fit the same model but with logged weekly wages. Give an interpretation to the regression coefficient for years of education. Which interpretation is more natural? > library(faraway) > data(uswages) > uswages[1:5,] # to see what the data set looks like wage educ exper race smsa ne mw so we pt 6085 771.60 18 18 0 1 1 0 0 0 0 23701 617.28 15 20 0 1 0 0 0 1 0 16208 957.83 16 9 0 1 0 0 1 0 0 2720 617.28 12 24 0 1 1 0 0 0 0 9723 902.18 14 12 0 1 0 1 0 0 0 > attach(uswages) > > fit1 = lm(wage ~ educ + exper) > summary(fit1) Call: lm(formula = wage ~ educ + exper) Residuals: Min 1Q Median 3Q Max -1018.23 -237.86 -50.87 149.88 7228.61 Coefficients: Estimate Std. Error t value Pr(>|t|) (Intercept) -242.7994 50.6816 -4.791 1.78e-06 *** educ 51.1753 3.3419 15.313 < 2e-16 *** exper 9.7748 0.7506 13.023 < 2e-16 *** --- Signif. codes: 0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1 Residual standard error: 427.9 on 1997 degrees of freedom Multiple R-Squared: 0.1351, Adjusted R-squared: 0.1343 F-statistic: 156 on 2 and 1997 DF, p-value: < 2.2e-16

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

View Full Document
The fitted regression function is wage = – 242.7994 + 51.1753 * educ + 9.7748 * exper. The regression coefficient for years of education is 51.1753. We would expect weekly wages to
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 04/29/2010 for the course STAT stat 420 taught by Professor Stepanov during the Spring '07 term at University of Illinois at Urbana–Champaign.

### Page1 / 8

420Hw04ans - STAT 420 Homework #4 Fall 2007 2.2 The dataset...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online