Regression birthweight on smoker, alcohol, and nprevist. Call: lm(formula = birt
ID: 1224081 • Letter: R
Question
Regression birthweight on smoker, alcohol, and nprevist.
Call:
lm(formula = birthweight ~ smoker)
Residuals:
Min 1Q Median 3Q Max
-3007.06 -313.06 26.94 366.94 2322.94
Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) 3432.06 11.87 289.115 <2e-16 ***
smoker -253.23 26.95 -9.396 <2e-16 ***
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 583.7 on 2998 degrees of freedom
Multiple R-squared: 0.0286, Adjusted R-squared: 0.02828
F-statistic: 88.28 on 1 and 2998 DF, p-value: < 2.2e-16
a. Regress birthweight on smoker. What is the estimated effect of smoking on birth weight?
Call:
lm(formula = birthweight ~ smoker + alcohol + nprevist)
Residuals:
Min 1Q Median 3Q Max
-2733.53 -307.57 21.42 358.09 2192.70
Coefficients:
Estimate Std. Error t value Pr(>|t|)
(Intercept) 3051.249 34.016 89.701 < 2e-16 ***
smoker -217.580 26.680 -8.155 5.07e-16 ***
alcohol -30.491 76.234 -0.400 0.689
nprevist 34.070 2.855 11.933 < 2e-16 ***
---
Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Residual standard error: 570.5 on 2996 degrees of freedom
Multiple R-squared: 0.07285, Adjusted R-squared: 0.07192
F-statistic: 78.47 on 3 and 2996 DF, p-value: < 2.2e-16
Explanation / Answer
i did not understand what should calculate from the above data