This is the website of Yihui Xie - http://yihui.name. I'm currently a first-year PhD student in the Department of Statistics, Iowa State University.

› Current Work

Brownian MotionStatistics does not mean whole pages of Greek letters; there are a lot of things to see. I have been working on an R package named animation which aims at demonstrating statistical theories and methods through animations, and turning statistical ideas into animations.

Law of Large NumbersThe technical implementation looks simple but effective, and the critical point is how to express the statistical ideas clearly in animations, which makes me think over and over again.

## Brownian Motion follows cum. sums of Gaussian rv's
bm.mat = replicate(2, apply(matrix(rnorm(2000), 200, 10), 
    2, cumsum), simplify = FALSE)
## plot each step and pause for 0.05 secs
for (i in seq_len(200)) {
    plot(bm.mat[[1]][i, ], bm.mat[[2]][i, ], 
	    xlim = range(bm.mat[[1]]), 
	    ylim = range(bm.mat[[2]]), 
	    pch = 19, ann = FALSE, axes = FALSE)
    Sys.sleep(0.05)
} 

Simulation of QQ plotsWhen people know what I'm working on, they are often surprised: don't all statisticians derive mathematical formulae every day? An answer to this question is:

"I'm not an outlier; I just haven't found my distribution yet!

Simulation of QQ plotsAs I'm taking the Stat 500 course this semester, I'm also writing another R package named ISU.Stat500 with Hui and Tengfei, which can hopefully serve as a complement to the course materials.

› Resources

- The R Project (Statistical Computing & Graphics)
- The Omegahat Project (Infrastructure for Stat Computing)
- Milestones of Stat Graphics (History)

› Contact Me

3211 Snedecor Hall, Department of Statistics, Iowa State University
Ames, 50011, IA
Email: xie@yihui.name; Tel: 515-203-6609