Division of random variables

Sep 18, 2019       1 min Tag: casual
This is trivial math question but it once bothers me in the construction of Dirichlet process using stick breaking process. The context is that if $V \sim beta(1, M)$ and $\theta \sim Dirichlet (\bar \alpha)$...
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A utopian kitsch coated with xenophobia and chauvinism

Aug 18, 2019       4 mins     Tag: zombie
That said, xenophobism is xenophobism, no matter coated with a caucasian supremacism, or a seemingly-progressive popularism, or even when it is companied with a chauvinistic salute towards another group of straw men.
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Sharpe ratios

Aug 01, 2019       1 mins     Tag: zombie
This is a jitt question in Andrew’s class: to (by hand) approximate the standard deviation of X/Y if X is N(5,1) and Y is N(1,3).
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ABC, Model Misspecification, and Bimodality

Jun 18, 2019       5 mins     Tag: computation
Like importance sampling, ABC is in principle immune to metastability that MCMC has to suffer, but ABC is also problematic as we have no idea what it will converge to when the model is misspecified.
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non-parametric MLE

Jun 17, 2019       1 mins     Tag: zombies
When I talked to someone about the old proof the invariance of odds ratio in a respropective sampling, I mentioned the estimation of $q(x)$ is achieved by its non-parametric MLE or its empirical distribution (see...
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Should I reweight a case-control study?

Jun 01, 2019       14 mins     Tag: modeling causal
The odds ratio from a case-control study is exactly the same as in a cohort study, therefore I could fit a retrospective logistic regression as if it is prospective and report its MLE or Bayesian posterior distribution. But considering the sampling distribution shift, should I reweight it regardless?
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The Optimal Transport and Importance Sampling

May 22, 2019       3 mins     Tag: ad-hoc computation
Most statisticians-orientated introduction to optimal transport theory starts with the motivation: we can always obtain a one-D distribution $f(\theta)$ through its inverse cdf transformation
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Affordable Bayesian Neural Networks

May 20, 2019       10 mins     Tag: computation
We wrote a new paper on approximate Bayesian inference in deep network, with a similiar computation cost as point estimation.
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