A small, underpowered treasure trove?

A small, underpowered treasure trove? Posted by Andrew on 12 January 2017, 9:48 am Benjamin Kirkup writes: As you sometimes comment on such things; I’m forwarding you a journal editorial (in a society journal)that presents “lessons learned” from an associated research study. What caught my attention was the comment on the “notorious” design, the lack of “significant” results, and the “interesting data on nonsignificant associations.” Apparently, the work “does not serve to inform the regulatory decision-making process with respect to antimicrobial compounds” but is “still valuable and can be informative.” Given the commissioning of a lessons-learned, how do you think the scientific publishing community should handle manuscripts presenting work with problematic designs and naturally uninformative outcomes? The editorial in question is called Lessons Learned from Probing for Impacts of Triclosan and Triclocarban on Human Microbiomes, it is by Rolf Halden, and…
Original Post: A small, underpowered treasure trove?

The Prior: Fully comprehended last, put first, checked the least?

Priors are important in Bayesian inference. Some would even say : ” In Bayesian inference you can—OK, you must—assign a prior distribution representing the set of values the coefficient [i.e any unknown parameter] can be.” Although priors are put first in most expositions, my sense is that in most applications they are seldom considered first, are checked the least and actually fully comprehended last (or perhaps not fully at all). It reminds of the comical response of someone when asked for difficult directions – “If I wanted to go there, I wouldn’t start out from here.” Perhaps this is less comical – “If I am going to be doing a Bayesian analyses, I do not want to be responsible for getting and checking the prior. Maybe the domain expert should do that or just accept the default priors I find in…
Original Post: The Prior: Fully comprehended last, put first, checked the least?

StanCon 2017 Schedule

StanCon 2017 Schedule Posted by Daniel on 11 January 2017, 12:39 pm The first Stan Conference is next Saturday, January 21, 2017! If you haven’t registered, here’s the link: https://stancon2017.eventbrite.comI wouldn’t wait until the last minute — we might sell out before you’re able to grab a ticket. We’re up to 125 registrants now.(If we have any tickets left, they are $400 at the door.) Schedule. January 21, 2017. Time What 7:30 AM – 8:45 AM Registration and breakfast 8:45 AM – 9:00 AM Opening statements 9:00 AM – 10:00 AM Dev talk:Andrew Gelman:“10 Things I Hate About Stan” 10:00 AM – 10:30 AM Coffee 10:30 AM – 12:00 PM Contributed talks: Jonathan Auerbach, Rob Trangucci:“Twelve Cities: Does lowering speed limits save pedestrian lives?” Milad Kharratzadeh:“Hierarchical Bayesian Modeling of the English Premier League” Victor Lei, Nathan Sanders, Abigail Dawson:“Advertising Attribution Modeling…
Original Post: StanCon 2017 Schedule

When do stories work, Process tracing, and Connections between qualitative and quantitative research

When do stories work, Process tracing, and Connections between qualitative and quantitative research Posted by Andrew on 11 January 2017, 9:45 am Jonathan Stray writes: I read your “when do stories work” paper (with Thomas Basbøll) with interest—as a journalist stories are of course central to my field. I wondered if you had encountered the “process tracing” literature in political science? It attempts to make sense of stories as “case studies” and there’s a nice logic of selection and falsification that has grown up around this. This article by David Collier is a good overview of process tracing, with a neat typology of story-based theory tests. Besides being a good paper generally, section 6 of this paper by James Mahoney and Gary Goertz discusses why you want non-random case/story selection in certain types of qualitative research. This paper by Jack Levy…
Original Post: When do stories work, Process tracing, and Connections between qualitative and quantitative research

R packages interfacing with Stan: brms

R packages interfacing with Stan: brms Posted by Jonah on 10 January 2017, 8:45 pm Over on the Stan users mailing list I (Jonah) recently posted about our new document providing guidelines for developing R packages interfacing with Stan. As I say in the post and guidelines, we (the Stan team) are excited to see the emergence of some very cool packages developed by our users. One of these packages is Paul Bürkner’s brms. Paul is currently working on his PhD in statistics at the University of Münster, having previously studied psychology and mathematics at the universities of Münster and Hagen (Germany). Here is Paul writing about brms: The R package brms implements a wide variety of Bayesian regression models using extended lme4 formula syntax and Stan for the model fitting. It has been on CRAN for about one and a…
Original Post: R packages interfacing with Stan: brms

I’ve said it before and I’ll say it again

I’ve said it before and I’ll say it again Posted by Andrew on 10 January 2017, 4:02 pm Ryan Giordano, Tamara Broderick, and Michael Jordan write: In Bayesian analysis, the posterior follows from the data and a choice of a prior and a likelihood. One hopes that the posterior is robust to reasonable variation in the choice of prior, since this choice is made by the modeler and is often somewhat subjective. A different, equally subjectively plausible choice of prior may result in a substantially different posterior, and so different conclusions drawn from the data. . . . To which I say: ,s/choice of prior/choice of prior and data model/g Yes, the choice of data model (from which comes the likelihood) is made by the modeler and is often somewhat subjective. In those cases where the data model is not chosen…
Original Post: I’ve said it before and I’ll say it again

Problems with randomized controlled trials (or any bounded statistical analysis) and thinking more seriously about story time

In 2010, I wrote: As a statistician, I was trained to think of randomized experimentation as representing the gold standard of knowledge in the social sciences, and, despite having seen occasional arguments to the contrary, I still hold that view, expressed pithily by Box, Hunter, and Hunter (1978) that “To find out what happens when you change something, it is necessary to change it.” At the same time, in my capacity as a social scientist, I’ve published many applied research papers, almost none of which have used experimental data. Randomized controlled trials (RCTs) have well-known problems with realism or validity (a problem that researchers try to fix using field experiments, but it’s not always possible to have a realistic field experiment either), and cost/ethics/feasibility (which pushes researchers toward smaller experiments in more artificial settings, which in turn can lead to…
Original Post: Problems with randomized controlled trials (or any bounded statistical analysis) and thinking more seriously about story time

Time Inc. stoops to the level of the American Society of Human Genetics and PPNAS?

Do anyone out there know anyone at Time Inc? If so, I have a question for you. But first the story: Mark Palko linked to an item from Barry Petchesky pointing out this article at the online site of Sports Illustrated Magazine. Here’s Petchesky: Over at Sports Illustrated, you can read an article about Tom Brady’s new line of sleepwear for A Company That Makes Stretchy Workout Stuff. The article contains the following lines: “The TB12 Sleepwear line includes full-length shirts and pants—and a short-sleeve and shorts version—with bioceramics printed on the inside.” “The print, sourced from natural minerals, activates the body’s natural heat and reflects it back as far infrared energy…” “The line, available in both men’s [link to store for purchase] and women’s [link to store for purchase] sizes, costs between $80 to $100 [link to store for…
Original Post: Time Inc. stoops to the level of the American Society of Human Genetics and PPNAS?

Confirmation bias

Confirmation bias Posted by Andrew on 9 January 2017, 9:22 am Shravan Vasishth is unimpressed by this evidence that was given to support the claim that being bilingual postpones symptoms of dementia: My reaction: Seems like there could be some selection issues, no? Shravan: Also, low sample size, and confirming what she already believes. I would be more impressed if she found evidence against the bilingual advantage. Me: Hmmm, that last bit is tricky, as there’s also a motivation for people to find surprising, stunning results. Shravan: Yes, but you will never find that this surprising, stunning result is something that goes against the author’s own previously published work. It always goes against someone else’s. I find this issue to be the most surprising and worrying of all, even more than p-hacking, that we only ever find evidence consistent with our…
Original Post: Confirmation bias

The Lure of Luxury

From the sister blog, a response to an article by psychologist Paul Bloom on why people own things they don’t really need: Paul Bloom argues that humans dig deep, look beyond the surface, and attend to the nonobvious in ways that add to our pleasure and appreciation of the world of objects. I [Susan] wholly agree with that analysis. My objection, however, is that he does not go far enough. There is a dark side to our infatuation by and obsession with the past. Our focus on historical persistence reveals not just appreciation and pleasure, but also bigotry and cruelty. Bloom’s story is incomplete without bringing these cases to light. All the examples that Bloom discusses involve what we might call positive contagion—an object gains value because of its link to a beloved individual, history, or brand. This positive glow…
Original Post: The Lure of Luxury