Lots of activity this week, as usual. * Lots of people got involved in pushing Stan 2.16 and interfaces out the door; Sean Talts got the math library, Stan library (that’s the language, inference algorithms, and interface infrastructure), and CmdStan out, while Allen Riddell got PyStan 2.16 out and Ben Goodrich and Jonah Gabry are […]

**Stan**category.

## Stan Weekly Roundup, 16 June 2017

We’re going to be providing weekly updates for what’s going on behind the scenes with Stan. Of course, it’s not really behind the scenes, because the relevant discussions are at stan-dev GitHub organization: this is the home of all of our source repos; design discussions are on the Stan Wiki Stan Discourse Groups: this is […]

## SPEED: Parallelizing Stan using the Message Passing Interface (MPI)

Sebastian Weber writes: Bayesian inference has to overcome tough computational challenges and thanks to Stan we now have a scalable MCMC sampler available. For a Stan model running NUTS, the computational cost is dominated by gradient calculations of the model log-density as a function of the parameters. While NUTS is scalable to huge parameter spaces, […]

## PhD student fellowship opportunity! in Belgium! to work with us! on the multiverse and other projects on improving the reproducibility of psychological research!!!

[image of Jip and Janneke dancing with a cat] Wolf Vanpaemel and Francis Tuerlinckx write: We at the Quantitative Psychology and Individual Differences, KU Leuven, Belgium are looking for a PhD candidate. The goal of the PhD research is to develop and apply novel methodologies to increase the reproducibility of psychological science. More information can […]

## UK election summary

The Conservative party, led by Theresa May, defeated the Labour party, led by Jeremy Corbyn. The Conservative party got 42% of the vote, Labour got 40% of the vote, and all the other parties received 18% between them. The Conservatives ended up with 51.5% of the two-party vote, just a bit less than Hillary Clinton’s […]

## Using external C++ functions with PyStan & radial velocity exoplanets

Dan Foreman-Mackey writes: I [Mackey] demonstrate how to use a custom C++ function in a Stan model using the Python interface PyStan. This was previously only possible using the R interface RStan (see an example here) so I hacked PyStan to make this possible in Python as well. . . . I have some existing […]

## U.K. news article congratulates YouGov on using modern methods in polling inference

Mike Betancourt pointed me to this news article by Alan Travis that is refreshingly positive regarding the use of sophisticated statistical methods in analyzing opinion polls. Here’s Travis: Leading pollsters have described YouGov’s “shock poll” predicting a hung parliament on 8 June as “brave” and the decision by the Times to splash it on its […]

## Hello, world! Stan, PyMC3, and Edward

Being a computer scientist, I like to see “Hello, world!” examples of programming languages. Here, I’m going to run down how Stan, PyMC3 and Edward tackle a simple linear regression problem with a couple of predictors. No, I’m not going to take sides—I’m on a fact-finding mission. We (the Stan development team) have been trying […]

## Stan programmer position at Columbia

We are hiring a Staff Associate who will be supporting development projects related to the open-source, state-of-the-art, probabilistic programming language and Bayesian inference engine Stan, an open-source, state-of-the-art Bayesian inference engine. The incumbent will be responsible for software development/programming, and programming updates by bringing all models up to current stats and coding standards; work on […]

## Come to Seattle to work with us on Stan!

Our colleague Jon Wakefield in the Department of Biostatistics at the University of Washington is interested in supervising a 2-year postdoc through this training program. We’re interested in finding someone who would with Jon and another faculty member (who is assigned on the basis of interests) on exciting projects in spatio-temporal modeling and the environmental […]

## StanCon 2018 is live!

This post is by Mike. We had so much fun at StanCon 2017 that we decided to do it again! This year’s conference will take place over three days, from Wednesday January 10, 2018 to Friday January 12, 2018, at the beautiful Asilomar Conference Grounds in Pacific Grove, California. In addition to talks and open discussion, […]

## The Other Side of the Night

Don Green points us to this quantitative/qualitative meta-analysis he did with Betsy Levy Paluck and Seth Green. The paper begins: This paper evaluates the state of contact hypothesis research from a policy perspective. Building on Pettigrew and Tropp’s (2006) influential meta-analysis, we assemble all intergroup contact studies that feature random assignment and delayed outcome measures, […]

## This company wants to hire people who can program in R or Python and do statistical modeling in Stan

Doug Puett writes: I am a 2012 QMSS [Columbia University Quantitative Methods in Social Sciences] grad who is currently trying to build a Data Science/Quantitative UX team, and was hoping for some advice. I am finding myself having a hard time finding people who are really interested in understanding people and who especially are excited […]

## Design top down, Code bottom up

Top-down design means designing from the client application programmer interface (API) down to the code. The API lays out a precise functional specification, which says what the code will do, not how it will do it. Coding bottom up means coding the lowest-level foundations first, testing them, then continuing to build. Sometimes this requires dropping […]

## A continuous hinge function for statistical modeling

This comes up sometimes in my applied work: I want a continuous “hinge function,” something like the red curve above, connecting two straight lines in a smooth way. Why not include the sharp corner (in this case, the function y=-0.5*x if x<0 or y=0.2*x if x>0)? Two reasons. First, computation: Hamiltonian Monte Carlo can trip […]

## Using Stan for week-by-week updating of estimated soccer team abilites

Milad Kharratzadeh shares this analysis of the English Premier League during last year’s famous season. He fit a Bayesian model using Stan, and the R markdown file is here. The analysis has three interesting features: 1. Team ability is allowed to continuously vary throughout the season; thus, once the season is over, you can see […]

## Update rstanarm to version 2.15.3

Ben Goodrich writes: We just released rstanarm 2.15.3, which fixed a major bug that was introduced back in January with the 2.14.1 release where models of the form stan_glmer(y ~ … + (1 | group1) + (1 | group2), family = binomial()) would produce WRONG RESULTS. This only applies to Bernoulli models with multiple group-specific […]

## Prior choice recommendations wiki !

Here’s the wiki, and here’s the background: Our statistical models are imperfect compared to the true data generating process and our complete state of knowledge (from an informational-Bayesian perspective) or the set of problems over which we wish to average our inferences (from a population-Bayesian or frequentist perspective). The practical question here is what model […]