man/figures/DiffMZRainMud.R

In umx: Structural Equation Modeling and Twin Modeling in R

data(twinData)
df = umx_scale_wide_twin_data(varsToScale= c("ht", "wt"), sep = "", data= twinData, twins = 1:2)
df$xDiff = df[, "ht1"] - df[, "ht2"]
df$yDiff = df[, "wt1"] - df[, "wt2"]

p = umxDiffMZ(x="ht", y="wt", labxy = c(x=-.4,y=1), data = subset(df, abs(yDiff - xDiff) < .09), sep = "")
p = p + labs(
	# title = "MZ twin intra-pair differences",
	x     = "Difference in exposure to rain (T1 - T2)",
	y     = "Difference in mud (T1 - T2)"
)
p = p + annotate("text", x=  .4, y = -.35, label = "Twin 1 goes out in the rain more,\nand has more mud on his shoes", family="Optima", size=4)
p = p + geom_curve(data = data.frame(x1 = .5, y1 = -.22, x2 = .85, y2 = .85), aes(x = x1, y = y1, xend = x2, yend = y2), arrow = arrow(length = unit(0.4, "cm")) )
p = p + annotate("text", x= -.5, y =  .50, label = "Twin 1 seldom walks in rain,\nand has less mud on his shoes", family="Optima", size=4)
p = p + geom_curve(data = data.frame(x1 = -.75, y1 = .35, x2 = -.55, y2 = -.65), aes(x = x1, y = y1, xend = x2, yend = y2), arrow = arrow(length = unit(0.4, "cm")) )
p
# p + geom_segment(aes(x = 1, y = 2, xend = 3, yend = 4), arrow = arrow(length = unit(0.50, "cm")) )