Richard McElreath 🐈‍⬛

@rmcelreath.bsky.social

18223 Followers 1409 Following

Anthropologist - Bayesian modeling - science reform - cat and cooking content too - Director @ MPI for evolutionary anthropology https://www.eva.mpg.de/ecology/staff/richard-mcelreath/

large cat flopping on a small lap
Gustave Elfving, on right looking smoking hot, thinking about geometry no doubt.
curve(1/sqrt(x),from=1,to=100,xlab="n",ylab="1/sqrt(n)",lwd=2)
Let me emphasize: the difficulty of changing the outcomes of the prazosin meta-analyses is an artifact of their statistics, and not because of the strength of evidence for prazosin. The prazosin meta-analyses include mostly small trials with large effects. The standard random-effects meta-analytic approach, in essence, overweighs small studies by presuming that each study reflects a distinct effect in that individual trial.7 In the Zhang et al. (2019) meta-analysis, for instance, the 304-subejct PACT trial was weighted as 15.6% for the nightmare outcome, while the 13-subject cross-over trial (Taylor et al., 2008) was weighted at 13.6%. The approaches of the other meta-analyses are very similar. No one seriously believes that a 13 person cross-over trial should count as much as the PACT trial, and yet, that’s what the meta-analyses argue.
First paragraph of Albert Einstein's 1917 paper Zur Quantentheorie der Strahlung
LaTeX editing window and PDF preview
Postcard for the city of Leipzig, showing photos of invasive raccoons and nutria that live and thrive in the city.
Excerpt from a published paper: Availability of data and materials Data will be posted publicly on osf.io upon acceptance of the publication. If editor would like the data as part of review, please let us know.
plate of chicken with rice
3.4.5 What is r? We’vecomefarenoughnowthatwecanspelloutmoreclearly what the r in Hamilton’s rule is and is not. r is not Pr(A|A). It is also easy to see from Equations 3.7 and3.8thatr ismostdefinitelynot thechancethattherecip- ient has a given allele, given that the donor has it. This com- mon mis-definition of r arises from a basic misunderstanding. The recipient and donor can be alike simply because the al- lele is common in the population (p is large). Instead, r is the increased similarly of the donor and recipient relative to the population mean. Only in extreme cases, as when p ≈0 and pi = 1, will r = E(pj|pi). r is the extent to which actor’s genotype predicts re- cipients’ genotypes. We showed a fairly standard deriva- tion of r as a regression coefficient, as Hamilton presented it. The slopes of the lines in Figure 3.3 are measures of r. In calculus-speak, r is the partial derivative of pj with respect to pi, ∂pj/∂pi: the rate of change in recipients’ genotypes as a function of actors’ genotypes. One important consequence of this interpretation is that negative relatedness is possible. If being an altruist predicts that the recipient is less likely than chancetohavethealtruismallele, theslopeofthebest-fitline will be negative. You might think this is a weird and unlikely circumstance, but it might be important in some cases.
cat laying on an ottoman with a pile of fur and a brush
bag of marmite flavored crisps
cat on rug trying to survive heat wave
fluffy cat on back
forest plot of marginal posterior distributions of regression coefficients
The hedgehog gives nothing Away, keeping itself to itself. We wonder what a hedgehog Has to hide, why it so distrusts. We forget the god Under this crown of thorns. We forget that never again Will a god trust in the world.
Denote b y h t the probabilit y there is no coun t in the time in terv al t No w the prop osition R No coun t in t dt is the conjunction of the t w o prop ositions R No coun t in t No coun t in t t dt and so b y the indep endence of dieren t time in terv als the pro duct rule giv es h t dt h t dt or h t h t The solution with the eviden t initial condition h is h t e t
cat sleeping on window sill with two potted orchids
7H1. In 2007, The Wall Street Journal published an editorial (“We’re Num- ber One, Alas”) with a graph of corporate tax rates in 29 countries plot- ted against tax revenue. A badly fit curve was drawn in (reconstructed at right), seemingly by hand, to make the argument that the relationship between tax rate and tax revenue increases and then declines, such that higher tax rates can actually produce less tax revenue. I want you to actu- ally fit a curve to these data, found in data(Laffer). Consider models that use tax rate to predict tax revenue. Compare, using WAIC or PSIS, a straight-line model to any curved models you like. What do you conclude about the relationship between tax rate and tax revenue?
Wall Street Journal graph from 2007 showing national corporate tax rates against tax revenue as percent of GDP. There is a curve drawn up and over the and down the other side of the points, but the curve is mainly outside the cloud of data.
title slide for talk "A Guerrilla Approach to Scientific Workflow"
PNAS 404 page, showing "No PaGe FOUNd" spelled out using elements of the periodic table
photo of a book page containing text „Freel University of Berlin“
still from a short about making mashed potatoes. chef is holding a plate piled high with butter. caption: Ein paar Flocken Butter unterrĂźhren
pic from wikipedia article about Tuataras: Tuatara at Zealandia are given coloured beads on their heads for identification.
spaghetti and meatballs in a bowl with cheese on top
Translating the DAG in Figure 2B to structural equations, we have Y(t) = aZ, Y(t+1) = bZ + cY(t), ΔY = Y(t+1) – Y(t). Set all variances to 1 for simplicity. Then the total covariance between Z and ΔY is cov(Z,ΔY) = cov(Z,Y(t+1)) – cov(Z,Y(t)) = [b+ac] – [a] = b + a(c–1). Only when c=1 is the true direct effect b recovered without bias. If c<1, then the analysis will underestimate the influence of Z on Y(t+1).
cat on at patterned rig, body twisted so head is looking upwards but belly is exposed
section of terrible phylogeny showing "fly" embedded within plants, closely related to maize and rice
poster for the film "La Chute de L'Empire Romain" (Fall of the Roman Empire)
poster advertisement in Italien for the McFlurry Dubai Chocolate Style. photo taken in Naples airport
still from video explaining Lie algebras. caption: out that those pieces come from a fairly small list.
double rainbow seen at Ravello, Italy
Paradises Lost is a science fiction novella by American author Ursula K. Le Guin. It was first published in 2002 as part of the collection The Birthday of the World. It is set during a multigenerational voyage from Earth to a potentially habitable planet. The protagonists, Liu Hsing and Nova Luis, are members of the fifth generation born on the ship. The story follows them as they deal with members of a religious cult who believe the ship ought not to stop at its intended destination. They also face a crisis brought on by a drastic change in the ship's schedule. The novella has since been anthologized as well as adapted into an opera of the same name.
same cat sleeping now
cat sitting in a person’s lap, looking at camera
kitten with giant ears
cat looking at camera
still from quoted video with caption "It's a norm in the field." Where "it" in context means data fraud.
8.3 Costly choice and sensory bias Lande’s model is useful because it exposes the logic of the runaway process in a particularly simple way. However, the model suffers from two related deficiencies: 1. The runaway process can’t really go on forever. You would have peacocks the size of Jupiter in no time at all. Something must bring the evolution of the male trait to a halt. 2. Female choice is costless. This may be approxi- mately true in many cases, but approximately is not good enough in this case. When the line is stable, the male trait stops changing, and the cost of choice, no matter how weak, will govern the evolution of female preferences. When the line is unstable, something must stop the male trait from evolving, and when it does, once again the cost of female choice will predominate.
chicken and rice with lettuce and tomato drizzled with garlic mayo sauce
The Katy Perry connection When pop star Katy Perry denied plagiarism in the song ‘Dark Horse’ (2013), Patrick provided expert evidence supporting her case. His evidence drew on a method he’s developed in his research that looks at melodies as if they were mutating viruses. Along with the School of Psychology’s Professor Quentin Atkinson, he created an algorithm to compare the sequences of notes in songs to create a kind of ‘family tree’ of ancestor and descendant songs, based on alterations that have occurred in the music as it has been passed down. Patrick has applied the technique to collections of thousands of Japanese folk songs and traditional British-American ballads such as ‘The Elfin Knight’, a song from the 1600s that mutated into what we know today as ‘Scarborough Fair’.
cute hedgehog curled up and resting but arosed from slumber by a tasty bit of fruit
Kombucha girls no yes meme. No: Wahlreporter (Election reporter). Yes: Wal-Reporter (Whale reporter)
Marcy from Adventure Time sitting dressed in all black, wearing sunglasses, with a parasol shading her
beef stew in pot
shakshuka simmering in a cast iron skillet
short screen recording of interactive workflow graph, showing highlighting of node parents and expansion of missing descendent (type-based error checking)
picture of two firefighters trying to extinguish a very large dumpster fire with a small hose. text on dumpster: INFERENCE IN THE BIOLOGICAL SCIENCES. text on fire fighters: ME AND MY FRIENDS
interactive map and synchronized text from book 2 of the Iliad, the passage listing all the blasted ship captains and the towns they came from
video of a group of nutria eating carrots happily
workflow graph showing the upstream parents of the Effect_Area node
screen cap from "The Wire". Caption: MY NAME IS MY NAME
drawing of a sperm whale with the name "Pinchy" next to it