What is a Linear Trend, by the way?

January 2, 2017
By
What is a Linear Trend, by the way?

I had a very strange discussion on twitter (yes, another one), about regression curves. I think it started with a tweet based on some xkcd picture (just for fun, because it was New Year’s Day) “don’t trust linear regressions” https://t.co/exUCvyRd1G pic.twitter.com/O6rBJfkULa — Arthur Charpentier (@freakonometrics) 1 janvier 2017 There were comments on that picture, by econometricians, mainly about ‘significant’ trends when datasets are very noisy. And I mentioned a graph…

Read more »

May the Force of R be With You, Always!

January 2, 2017
By
May the Force of R be With You, Always!

With a Telegram account connected to @TeleR, the force of R can always be with me, where I have data. The following is a screenshot of my mobile: If you want to have R where you are too, you only need a Telegram account; then, you have to search for...

Read more »

How to perform PCA on R

January 1, 2017
By
How to perform PCA on R

This is a practical tutorial on performing PCA on R. If you would like to understand how PCA works, please see my plain English explainer here. Reminder: Principal Component Analysis (PCA) is a method used to reduce the number of variables in a dataset. We are using R’s USArrests dataset, a dataset from 1973 showing, […]

Read more »

How to perform PCA on R

January 1, 2017
By
How to perform PCA on R

This is a practical tutorial on performing PCA on R. If you would like to understand how PCA works, please see my plain English explainer here. Reminder: Principal Component Analysis (PCA) is a method used to reduce the number of variables in a dataset. We are using R’s USArrests dataset, a dataset from 1973 showing, […]

Read more »

Comment of the year

January 1, 2017
By

In our discussion of research on the possible health benefits of a low-oxygen environment, Raghu wrote: This whole idea (low oxygen -> lower cancer risk) seems like a very straightforward thing to test in animals, which one can move to high and low oxygen environments . . . And then Llewelyn came in for the […] The post Comment of the year appeared first on Statistical Modeling, Causal Inference, and…

Read more »

New Year’s Reading

December 31, 2016
By
New Year’s Reading

New Year's resolution - read more Econometrics!Bürgi, C., 2016. What do we lose when we average expectations? RPF Working Paper No. 2016-013, Department of Economics, George Washington University.Cox, D.R., 2016. Some pioneers of modern statistical th...

Read more »

Transformative treatments

December 31, 2016
By
Transformative treatments

Kieran Healy and Laurie Paul wrote a new article, “Transformative Treatments,” (see also here) which reminds me a bit of my article with Guido, “Why ask why? Forward causal inference and reverse causal questions.” Healy and Paul’s article begins: Contemporary social-scientific research seeks to identify specific causal mechanisms for outcomes of theoretical interest. Experiments that […] The post Transformative treatments appeared first on Statistical Modeling, Causal Inference, and Social Science.

Read more »

“Kevin Lewis and Paul Alper send me so much material, I think they need their own blogs.”

December 30, 2016
By

In my previous post, I wrote: Kevin Lewis and Paul Alper send me so much material, I think they need their own blogs. It turns out that Lewis does have his own blog. His latest entry contains a bunch of links, starting with this one: Populism and the Return of the “Paranoid Style”: Some Evidence […] The post “Kevin Lewis and Paul Alper send me so much material, I think…

Read more »

Two unrelated topics in one post: (1) Teaching useful algebra classes, and (2) doing more careful psychological measurements

December 30, 2016
By

Kevin Lewis and Paul Alper send me so much material, I think they need their own blogs. In the meantime, I keep posting the stuff they send me, as part of my desperate effort to empty my inbox. 1. From Lewis: “Should Students Assessed as Needing Remedial Mathematics Take College-Level Quantitative Courses Instead? A Randomized […] The post Two unrelated topics in one post: (1) Teaching useful algebra classes, and…

Read more »

A Roundup of Year-End News Graphics Roundups

December 30, 2016
By
A Roundup of Year-End News Graphics Roundups

The end of the year is always a good time to look back at the great work done in the world of news graphics – and this year in particular, to relive all the heartbreak and disillusionment. Here is a list of year-end news graphics round-ups for your enjoyment and edification. The New York Times, 2016: […]

Read more »

Why Not Join The Replication Network?

December 30, 2016
By
Why Not Join The Replication Network?

I've been a member of The Replication Network (TRN) for some time now, and I commend it to you.I received the End-of-the-Year Update for the TRN today, and I'm taking the liberty of reproducing it below in its entirety in the hope that you may con...

Read more »

a Galton-Watson riddle

December 29, 2016
By
a Galton-Watson riddle

The Riddler of this week has an extinction riddle which summarises as follows: One observes a population of N individuals, each with a probability of 10⁻⁴ to kill the observer each day. From one day to the next, the population decreases by one individual with probability K√N 10⁻⁴ What is the value of K that […]

Read more »

Post Post-Truth

December 29, 2016
By
Post Post-Truth

postfaktisch ‘Fake-news’ and ‘post-truth’ (postfaktisch) are the words dominating today many discussions about truth in communication. ' ... in post-truth [post] has a meaning more like ‘belonging to a time in which the specified concept [truth] has become unimportant or irrelevant’' (https://www.oxforddictionaries.com/press/news/2016/11/15/WOTY-16). False information or even lies are not new in the information business. And therefore many, […]

Read more »

“The Pitfall of Experimenting on the Web: How Unattended Selective Attrition Leads to Surprising (Yet False) Research Conclusions”

December 29, 2016
By
“The Pitfall of Experimenting on the Web: How Unattended Selective Attrition Leads to Surprising (Yet False) Research Conclusions”

Kevin Lewis points us to this paper by Haotian Zhou and Ayelet Fishbach, which begins: The authors find that experimental studies using online samples (e.g., MTurk) often violate the assumption of random assignment, because participant attrition—quitting a study before completing it and getting paid—is not only prevalent, but also varies systemically across experimental conditions. Using […] The post “The Pitfall of Experimenting on the Web: How Unattended Selective Attrition Leads…

Read more »

“I thought it would be most unfortunate if a lab . . . wasted time and effort trying to replicate our results.”

December 29, 2016
By
“I thought it would be most unfortunate if a lab . . . wasted time and effort trying to replicate our results.”

Mark Palko points us to this news article by George Dvorsky: A Harvard research team led by biologist Douglas Melton has retracted a promising research paper following multiple failed attempts to reproduce the original findings. . . . In June 2016, the authors published an article in the open access journal PLOS One stating that […] The post “I thought it would be most unfortunate if a lab . .…

Read more »

Sorry, but no, you can’t learn causality by looking at the third moment of regression residuals

December 28, 2016
By

Under the subject line “Legit?”, Kevin Lewis pointed me to this press release, “New statistical approach will help researchers better determine cause-effect.” I responded, “No link to any of the research papers, so cannot evaluate.” In writing this post I thought I’d go further. The press release mentions 6 published articles so I googled the […] The post Sorry, but no, you can’t learn causality by looking at the third…

Read more »

More on the History of Distributed Lag Models

December 28, 2016
By
More on the History of Distributed Lag Models

In a follow-up to my recent post about Irving Fisher's contribution to the development of distributed lag models,  Mike Belongia emailed me again with some very interesting material. He commented:"While working with Peter Ireland to crea...

Read more »

The contaminated normal distribution

December 28, 2016
By
The contaminated normal distribution

How can you generate data that contains outliers in a simulation study? The contaminated normal distribution is a simple but useful distribution you can use to simulate outliers. The distribution is easy to explain and understand, and it is also easy to implement in SAS. What is a contaminated normal […] The post The contaminated normal distribution appeared first on The DO Loop.

Read more »

More on Orthogonal Regression

December 27, 2016
By
More on Orthogonal Regression

Some time ago I wrote a post about orthogonal regression. This is where we fit a regression line so that we minimize the sum of the squares of the orthogonal (rather than vertical) distances from the data points to the regression line.Subsequently...

Read more »

Ethics and statistics

December 27, 2016
By

For a few years now, I’ve been writing a column in Chance. Below are the articles so far. This is by no means an exhaustive list of my writings on ethics and statistics but at least I thought it could help to collect these columns in one place. Ethics and statistics: Open data and open […] The post Ethics and statistics appeared first on Statistical Modeling, Causal Inference, and Social…

Read more »

Chopped legs, and abridged analyses

December 27, 2016
By
Chopped legs, and abridged analyses

Reader Glenn T. was not impressed by the graphical talent on display in the following column chart (and others) in a Monkey Cage post in the Washington Post: Not starting column charts at zero is like having one's legs chopped...

Read more »

ASA President meets OCCAM data

December 27, 2016
By

Just leaving this quote from ASA President Jessica Utts here (Source: Amstat News Dec 2016): A few days ago, I was in Vietnam and took a four-hour bus ride from Ha Long Bay to Hanoi. When I arrived, my fitness tracker had given me credit for taking 9,124 steps and climbing 81 flights of stairs during those four hours, even though I only left my seat once during a short…

Read more »

Objects of the class “George Orwell”

December 27, 2016
By
Objects of the class “George Orwell”

George Orwell is an exemplar in so many ways: a famed truth-teller who made things up, a left-winger who mocked left-wingers, an author of a much-misunderstood novel (see “Objects of the class ‘Sherlock Holmes,’”) probably a few dozen more. But here I’m talking about Orwell’s name being used as an adjective. More specifically, “Orwellian” being […] The post Objects of the class “George Orwell” appeared first on Statistical Modeling, Causal…

Read more »


Subscribe

Email:

  Subscribe