Honglei Xie

Recent Posts

  • December 04, 2015

    DREAM Big Data Challenge

    Last summer I and my colleagues in Ontario Institute for Cancer Research teamed up together as Chipmunks, participated in one of DREAM big data challenges: Acute Myeloid Leukemia Outcome Prediction Challenge (AML). Similar to Kaggle, we were asked...

  • December 01, 2015

    Adaptive Thresholding

    Motivated by applications in a wide range of fields in signal processing, social science, finance, genetics etc, statistical inference in high dimensional data is a problem of greatinterest. Covariance matrix plays an important role in many fundam...

  • November 30, 2015

    SAS tricks: Assign the Same Value within Group

    We often use NODUPKEY or NODUP with BY statement to filter out duplicates in terms of specified variables in BY. However, the problem I dealt with today seemed to be a bit tricky. And I surprisingly found out how powerful RETAIN statement is! Let ...

  • November 29, 2015

    几首诗

    读到几首诗,甚对胃口。旅次朔方 — 刘皂(唐)客舍并州已十霜,归心日夜忆咸阳。无端更渡桑干水,却望并州是故乡。 波兰来客(节选)— 北岛那时我们有梦,关于文学,关于爱情,关于穿越世界的旅行。如今我们深夜饮酒,杯子碰到一起,都是梦破碎的声音。

  • November 29, 2015

    Brief Intro to My Master Research Paper

    Randomized experiments are generally considered as the most effective way for estimating treatment efficacy. However, sometimes they are either too slow or prohibitively expensive to conduct in practice. In many studies, observational data seems t...