# 2 (a)
attach(vowlax.df)
temp = phonetic == "a" & speaker == "67"
x = dur[temp]
y = F1[temp]
cor.test(x, y)

# 2 (b) 
temp = phonetic == "a" & speaker == "68"
x = rms[temp]
y = F1[temp]
cor.test(x, y)

# 2 (c)
temp = phonetic == "I" & speaker == "68"
x = F1[temp]
y = F2[temp]
cor.test(x, y)

# 4 (a)
temp = dip.l == "aI" & dip.spkr == "67"
y = dcut(dip.fdat[temp,2], .8, prop=T)
x = dur(dip[temp,])
cor.test(x, y)

# 4(b)
y2 = dcut(dip.fdat[temp,2], .8, prop=T) - dcut(dip.fdat[temp,2], .2, prop=T)
cor.test(x, y2)

# 4(c)
reg1 = lm(y ~ x)
reg2 = lm(y2 ~ x)
par(mfrow=c(1,2))
plot(x, y, xlab="Dauer (ms)", ylab="F2 (Hz)")
abline(reg1)
plot(x, y2, xlab="Dauer (ms)", ylab="F2 Unterschied (Hz)")
abline(reg2)