birthwt {MASS} | R Documentation |
The birthwt
data frame has 189 rows and 10 columns.
The data were collected at Baystate Medical Center, Springfield, Mass
during 1986.
low |
indicator of birth weight less than 2.5kg |
age |
mother's age in years |
lwt |
mother's weight in pounds at last menstrual period |
race |
mother's race (1 = white, 2 = black, 3 = other)
|
smoke |
smoking status during pregnancy |
ptl |
number of previous premature labours |
ht |
history of hypertension |
ui |
presence of uterine irritability |
ftv |
number of physician visits during the first trimester |
bwt |
birth weight in grams |
This data frame contains the following columns:
Hosmer, D.W. and Lemeshow, S. (1989) Applied Logistic Regression. New York: Wiley
data(birthwt) attach(birthwt) race <- factor(race, labels=c("white", "black", "other")) ptd <- factor(ptl > 0) ftv <- factor(ftv) levels(ftv)[-(1:2)] <- "2+" bwt <- data.frame(low=factor(low), age, lwt, race, smoke=(smoke>0), ptd, ht=(ht>0), ui=(ui>0), ftv) detach("birthwt") options(contrasts = c("contr.treatment", "contr.poly")) glm(low ~ ., binomial, bwt)