sp.mixnorm: Mixture of Spherical Normal Distributions

In kisungyou/RiemSphere: What the package doesas

Description

max loglkd; min ICs

Usage

sp.mixnorm(
  x,
  k = 2,
  init = c("kmeans", "random"),
  maxiter = 496,
  same.lambda = TRUE,
  version = c("soft", "hard", "stochastic")
)

Examples

## generate two-cluster data
mymu1 = c(0,0,0,1)        # center of class 1
mymu2 = c(-1,0,0,0)       # center of class 2
mymu3 = c(0,1/sqrt(2),-1/sqrt(2),0) # class 3

x1 = rvmf(50, mymu1, kappa=10)
x2 = rvmf(50, mymu2, kappa=15)
x3 = rvmf(50, mymu3, kappa=20)
xx = rbind(x1,x2,x3)

## apply clustering with different k values
mix2 <- sp.mixnorm(xx, k=2)
mix3 <- sp.mixnorm(xx, k=3)
mix4 <- sp.mixnorm(xx, k=4)

## compute 2-dimensional embedding for visualization
mds2d <- sp.mds(xx, ndim=2)
x  <- mds2d$embed[,1]
y  <- mds2d$embed[,2]

## compare via visualization
opar <- par(mfrow=c(1,3),pty="s")
plot(x,y,col=mix2$cluster,main="k=2 mixture",pch=19)
plot(x,y,col=mix3$cluster,main="k=2 mixture",pch=19)
plot(x,y,col=mix4$cluster,main="k=2 mixture",pch=19)
par(opar)

## extra visualization
## Not run: 
# run more models
mix5 <- sp.mixnorm(xx, k=5)
mix6 <- sp.mixnorm(xx, k=6)
mix7 <- sp.mixnorm(xx, k=7)
mix8 <- sp.mixnorm(xx, k=8)

# information criteria
xmat <- 2:8
ymat <- rbind(mix2$criteria, mix3$criteria, mix4$criteria, mix5$criteria, 
              mix6$criteria, mix7$criteria, mix8$criteria)
colnames(ymat) = colnames(mix2$criteria)

# plot with x11()
x11(width=12, height=6)
par(mfrow=c(2,4), pty="s")
plot(x, y, col=rainbow(8)[mix2$cluster], main="k=2 mixture", pch=19)
plot(x, y, col=rainbow(8)[mix3$cluster], main="k=3 mixture", pch=19)
plot(x, y, col=rainbow(8)[mix4$cluster], main="k=4 mixture", pch=19)
plot(x, y, col=rainbow(8)[mix5$cluster], main="k=5 mixture", pch=19)
plot(x, y, col=rainbow(8)[mix6$cluster], main="k=6 mixture", pch=19)
plot(x, y, col=rainbow(8)[mix7$cluster], main="k=7 mixture", pch=19)
plot(x, y, col=rainbow(8)[mix8$cluster], main="k=8 mixture", pch=19)
matplot(xmat, ymat, type="b", lwd=2, main="Info. Criteria",
        xlab="# clusters", col=1:4, lty=1:4, pch=1)
legend("topright", legend = colnames(ymat), col = 1:4, lty=1:4, pch=1)

## End(Not run) 

kisungyou/RiemSphere documentation built on April 11, 2020, 4:04 a.m.