# Observations on the ecological variability of Plantago media. Middle Russia, June 2002
# Possible way of analysis:
if(0){
tt <- read.table("http://ashipunov.info/shipunov/open/transect.txt", h=TRUE)
Str(tt) # asmisc.r
plot(LEAF.L ~ POSITION, data=tt)
abline(coef(line(tt$POSITION, tt$LEAF.L)))
tt.lm <- lm(LEAF.L ~ POSITION, data=tt)
summary(tt.lm)
plot(tt.lm, which=2)
plot(tt.lm, which=1)
plot(lm(LEAF.L ~ I(POSITION^2), data=tt), which=1)
plot(lm(LEAF.L ~ I(POSITION^3), data=tt), which=1)
AIC(tt.lm)
AIC(lm(LEAF.L ~ I(POSITION^2), data=tt))
AIC(lm(LEAF.L ~ I(POSITION^3), data=tt))
summary(lm(LEAF.L ~ I(POSITION^3), data=tt))
is.steppe <- with(tt, (LEAF.L > 110) & (LEAF.W < 50))
form <- factor(is.steppe, labels=c("common","steppe"))
cdplot(form ~ POSITION, data=tt)
summary(glm(form ~ POSITION, family=binomial, data=tt))
}
#
POSITION	Position along the transect (started from most sunny and dry spot and went towards the lake coast), m
LEAF.L	Leaf length, mm (from that point, all measurements are about the maximal leaf in rosette)
LEAF.W	Leaf width, mm
LEAF.MAXW	Leaf maximal width, mm
VEINS	Number of primary veins