chdage {aplore3}

CHDAGE data

Description

chdage dataset.

Usage

chdage

Format

A data.frame with 100 rows and 4 variables:

id

Identification code (1 - 100)

age

Age (Years)

agegrp

Age group (1: 20-39, 2: 30-34, 3: 35-39, 4: 40-44, 5: 45-49, 6: 50-54, 7: 55-59, 8: 60-69)

chd

Presence of CHD (1: No, 2: Yes)

Source

Hosmer, D.W., Lemeshow, S. and Sturdivant, R.X. (2013) Applied Logistic Regression, 3rd ed., New York: Wiley

Examples

head(chdage,  n = 10)
summary(chdage)

## Figure 1.1 p. 5
plot(as.integer(chd)-1 ~ age,
     pch = 20,
     main = "Figure 1.1 p. 5",
     ylab = "Coronary heart disease",
     xlab = "Age (years)",
     data = chdage)

## Table 1.2
with(chdage, addmargins(table(agegrp)))
with(chdage, addmargins(table(agegrp, chd)))
(Means <- with(chdage, tapply(as.integer(chd)-1, list(agegrp), mean)))

## Figure 1.2 p. 6
midPoints <- c(24.5, seq(32, 57, 5), 64.5)
plot(midPoints, Means, pch = 20,
     ylab = "Coronary heart disease (mean)",
     xlab = "Age (years)", ylim = 0:1,
     main = "Figure 1.2 p. 6")
lines(midPoints, Means)

## Table 1.3
summary( mod1.3 <- glm( chd ~ age, family = binomial, data = chdage ))

## Table 1.4
vcov(mod1.3)

## Computing OddsRatio and confidence intervals for age ...
exp(coef(mod1.3))[-1]
exp(confint(mod1.3))[-1, ]