Number of Boys in Two-Child Families
The number of boys in a sample of 2,444 two-child families.
A data frame with 3 observations on the following 2 variables.
a numeric vector
a numeric vector
Rodgers, J.L. and D. Doughty. 2001. Does having boys or girls run in the family? Chance Magazine Fall 2001: 8-13.
TwoKids
observed <- TwoKids$count
expected <- c(585.3, 1221.4, 637.3)
chisq.test(observed, p = expected, rescale.p = TRUE)
# Alternate calculation, using Pr[male] = 0.512
# and rbinom. See Figure 5.7-1
n <- sum(observed)
pr.m <- 0.512
pr.f <- 0.488
# Calculate the probabilities of 0, 1, and 2 males
(pr.0 <- pr.f^2)
(pr.1 <- pr.m * pr.f + pr.f * pr.m)
(pr.2 <- pr.m^2)
set.seed(1)
(expected2 <- c(rbinom(1, n, pr.0),
rbinom(1, n, pr.1),
rbinom(1, n, pr.2)))
chisq.test(observed, p = expected2, rescale.p = TRUE)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.