*Baayen より [#c9a81c58]
[[Analyzing Linguistic Data:http://www.amazon.co.jp/Analyzing-Linguistic-Data-Introduction-Statistics/dp/0521882591/]]
pp.105-
library(MASS)
x <- mvrnorm(n = 1000, mu = c(0,0),
Sigma = cbind(c(1, 0.8), c(0.8,1)))
# 単変量の場合の density 関数にあたるのが kde2d
persp(kde2d(x[,1], x[,2], n = 50),
phi = 30, theta = 20, # angle の指定
d = 10,
col = "lightblue",
shade = 0.75, ltheta = -100,
border = NA,
expand = 0.5,
xlab = "X",ylab ="Y", zlab = "density")
mtext("bivariate standard normal", 3, 1)
kde2d 関数の引数 n が分かりにくいが,x,y 座標の数
#ref(baayen106.png,center,nowrap,80%, lmreg による画像)