languageR (version 1.0)

faz: Frankfurter frequencies

Description

Frequencies of references to previous years in issues of the Frankfurter Allgemeine Zeiting published in 1994.

Usage

data(faz)

References

Pollman, T. and Baayen, R. H. (2001) Computing historical consciousness. A quantitative inquiry into the presence of the past in newspaper texts, Computers and the Humanities, 35, 237-253.

Examples

data(faz)
faz$Distance = 1:nrow(faz)

# ---- visualization

plot(log(faz$Distance), log(faz$Frequency + 1), 
xlab = "log Distance", ylab = "log Frequency")
abline(v = log(49), lty=1, col="red")   # 1945
abline(v = log(54), lty=1, col="red")   # 1940
abline(v = log(76), lty=2, col="blue")  # 1918
abline(v = log(80), lty=2, col="blue")  # 1914

# ---- breakpoint analysis

deviances = rep(0, nrow(faz)-1)
faz$LogFrequency = log(faz$Frequency + 1)
faz$LogDistance = log(faz$Distance)
for (pos in 1 : (nrow(faz)-1)) {                             # be patient
  breakpoint = log(pos)
  faz$ShiftedLogDistance = faz$LogDistance - breakpoint
  faz$PastBreakPoint = as.factor(faz$ShiftedLogDistance > 0)
  faz.both = lm(LogFrequency~ShiftedLogDistance:PastBreakPoint, data = faz)
  deviances[pos] = deviance(faz.both)
}
breakpoint = log(which(deviances == min(deviances)))

# ---- refit and plot

faz$ShiftedLogDistance = faz$LogDistance - breakpoint
faz$PastBreakPoint = as.factor(faz$ShiftedLogDistance > 0)
faz.both = lm(LogFrequency ~ ShiftedLogDistance:PastBreakPoint, data = faz)

plot(faz$LogDistance, faz$LogFrequency, 
xlab = "log Distance", ylab = "log Frequency", col = "darkgrey")
lines(faz$LogDistance, fitted(faz.both))