Jon Mellon
@jonmellon.bsky.social
Co-director British Election Study. Political Scientist and Data Scientist. Political science methods/political behavior/causal inference. Posts do not represent employer.
Pinned
Jon Mellon
@jonmellon.bsky.social
· Nov 14
Out now open access at
@ajpseditor.bsky.social. 194 potential exclusion-restriction violations for studies using weather as an instrumental variable onlinelibrary.wiley.com/doi/full/10....
@ajpseditor.bsky.social. 194 potential exclusion-restriction violations for studies using weather as an instrumental variable onlinelibrary.wiley.com/doi/full/10....
Reposted by Jon Mellon
Reposted by Jon Mellon
Camus clearly never had to work out what was wrong with district level outcomes at the 2007 Burkina Faso legislative elections
October 13, 2025 at 1:18 PM
Camus clearly never had to work out what was wrong with district level outcomes at the 2007 Burkina Faso legislative elections
Reposted by Jon Mellon
New blog post!
Let's say you have two measures meant to capture the same confounder. They're highly correlated. Can you still proceed with your regression analysis?
(I admit, the title is a bit of a spoiler)
www.the100.ci/2025/10/13/i...
Let's say you have two measures meant to capture the same confounder. They're highly correlated. Can you still proceed with your regression analysis?
(I admit, the title is a bit of a spoiler)
www.the100.ci/2025/10/13/i...
If you have two measures of the same confounder, you can just include both of them in your regression model
Sometimes, researchers worry about multicollinearity in situations where it’s actually a non-issue. Here’s one such scenario.
Imagine a situation where you are interested in the effect of X on Y (X...
www.the100.ci
October 13, 2025 at 1:14 PM
New blog post!
Let's say you have two measures meant to capture the same confounder. They're highly correlated. Can you still proceed with your regression analysis?
(I admit, the title is a bit of a spoiler)
www.the100.ci/2025/10/13/i...
Let's say you have two measures meant to capture the same confounder. They're highly correlated. Can you still proceed with your regression analysis?
(I admit, the title is a bit of a spoiler)
www.the100.ci/2025/10/13/i...
Has anyone had success stories (or can point me to writeups) with fine tuning frontier LLMs?
October 3, 2025 at 4:21 PM
Has anyone had success stories (or can point me to writeups) with fine tuning frontier LLMs?
Reposted by Jon Mellon
Education? Completed it, mate.
Last week, I defended my PhD thesis and am now a doctor!
Thank you to @robfordmancs.bsky.social and @jonmellon.bsky.social for being great supervisors for 4 years
And thanks to @sarahobolt.bsky.social and Ed Fieldhouse for their interesting feedback and discussion
Last week, I defended my PhD thesis and am now a doctor!
Thank you to @robfordmancs.bsky.social and @jonmellon.bsky.social for being great supervisors for 4 years
And thanks to @sarahobolt.bsky.social and Ed Fieldhouse for their interesting feedback and discussion
September 29, 2025 at 10:56 AM
Education? Completed it, mate.
Last week, I defended my PhD thesis and am now a doctor!
Thank you to @robfordmancs.bsky.social and @jonmellon.bsky.social for being great supervisors for 4 years
And thanks to @sarahobolt.bsky.social and Ed Fieldhouse for their interesting feedback and discussion
Last week, I defended my PhD thesis and am now a doctor!
Thank you to @robfordmancs.bsky.social and @jonmellon.bsky.social for being great supervisors for 4 years
And thanks to @sarahobolt.bsky.social and Ed Fieldhouse for their interesting feedback and discussion
Reposted by Jon Mellon
Rex W. Douglas PhD Applied Scientist (Remote/Austin)
Looking for full time and freelance projects.
Hoping for somewhere stable. I've never been more productive in my life, but mass layoffs and funding collapses have been endemic.
Looking for full time and freelance projects.
Hoping for somewhere stable. I've never been more productive in my life, but mass layoffs and funding collapses have been endemic.
September 24, 2025 at 4:29 PM
Rex W. Douglas PhD Applied Scientist (Remote/Austin)
Looking for full time and freelance projects.
Hoping for somewhere stable. I've never been more productive in my life, but mass layoffs and funding collapses have been endemic.
Looking for full time and freelance projects.
Hoping for somewhere stable. I've never been more productive in my life, but mass layoffs and funding collapses have been endemic.
Reposted by Jon Mellon
Help! ─ 𝗔𝗽𝗽𝗹𝗶𝗲𝗱 𝗦𝗰𝗶𝗲𝗻𝘁𝗶𝘀𝘁 open to work ─ Remote/Austin → www.rexdouglass.com
With new tools, I've been cooking:
▸ Machine-vision pipelines — RIOS Intelligent Machines
▸ Information-extraction pipelines — Microsoft
▸ Interactive SMS surveys — Pantheon Insights
With new tools, I've been cooking:
▸ Machine-vision pipelines — RIOS Intelligent Machines
▸ Information-extraction pipelines — Microsoft
▸ Interactive SMS surveys — Pantheon Insights
September 24, 2025 at 4:28 PM
Help! ─ 𝗔𝗽𝗽𝗹𝗶𝗲𝗱 𝗦𝗰𝗶𝗲𝗻𝘁𝗶𝘀𝘁 open to work ─ Remote/Austin → www.rexdouglass.com
With new tools, I've been cooking:
▸ Machine-vision pipelines — RIOS Intelligent Machines
▸ Information-extraction pipelines — Microsoft
▸ Interactive SMS surveys — Pantheon Insights
With new tools, I've been cooking:
▸ Machine-vision pipelines — RIOS Intelligent Machines
▸ Information-extraction pipelines — Microsoft
▸ Interactive SMS surveys — Pantheon Insights
Reposted by Jon Mellon
I remember around 1995 a woman knocked on the door, doing a survey about air fresheners. I never bought any so it didn't last long but I was quite excited that someone was asking my opinion about a product or service. At last! Finally, Gen X was being consulted!
Social scientists often bemoan falling survey response rates. A big part of the story has to be the proliferation of survey requests.
I took every survey I was invited to in an 8 day period and took 27 surveys totaling 33 minutes.
I took every survey I was invited to in an 8 day period and took 27 surveys totaling 33 minutes.
September 24, 2025 at 3:46 PM
I remember around 1995 a woman knocked on the door, doing a survey about air fresheners. I never bought any so it didn't last long but I was quite excited that someone was asking my opinion about a product or service. At last! Finally, Gen X was being consulted!
Social scientists often bemoan falling survey response rates. A big part of the story has to be the proliferation of survey requests.
I took every survey I was invited to in an 8 day period and took 27 surveys totaling 33 minutes.
I took every survey I was invited to in an 8 day period and took 27 surveys totaling 33 minutes.
September 24, 2025 at 1:49 PM
Social scientists often bemoan falling survey response rates. A big part of the story has to be the proliferation of survey requests.
I took every survey I was invited to in an 8 day period and took 27 surveys totaling 33 minutes.
I took every survey I was invited to in an 8 day period and took 27 surveys totaling 33 minutes.
I would argue this is actually about Bayesian inference
September 21, 2025 at 12:35 AM
I would argue this is actually about Bayesian inference
Come see our work on using LLMs to track political science research methods at APSA at 4pm today!
We find the latest LLMs beat graduate student RAs at extracting information from academic papers
We find the latest LLMs beat graduate student RAs at extracting information from academic papers
September 13, 2025 at 8:02 PM
Come see our work on using LLMs to track political science research methods at APSA at 4pm today!
We find the latest LLMs beat graduate student RAs at extracting information from academic papers
We find the latest LLMs beat graduate student RAs at extracting information from academic papers
Reposted by Jon Mellon
🚨DATA RELEASE 🚨
The BES team are pleased to announce the release of Wave 30 of the British Election Study Internet Panel.
Please follow the link below, and we look forward to seeing your research!
www.britishelectionstudy.com/bes-resource...
The BES team are pleased to announce the release of Wave 30 of the British Election Study Internet Panel.
Please follow the link below, and we look forward to seeing your research!
www.britishelectionstudy.com/bes-resource...
Release Note: British Election Study Internet Panel Wave 30 - The British Election Study
www.britishelectionstudy.com
September 6, 2025 at 1:21 PM
🚨DATA RELEASE 🚨
The BES team are pleased to announce the release of Wave 30 of the British Election Study Internet Panel.
Please follow the link below, and we look forward to seeing your research!
www.britishelectionstudy.com/bes-resource...
The BES team are pleased to announce the release of Wave 30 of the British Election Study Internet Panel.
Please follow the link below, and we look forward to seeing your research!
www.britishelectionstudy.com/bes-resource...
Reposted by Jon Mellon
Now elsevier have been harassing me personally to pay the invoice (several thousand dollars).
September 4, 2025 at 11:44 PM
Now elsevier have been harassing me personally to pay the invoice (several thousand dollars).
Has anyone else had experience with being harassed by @elsevierconnect.bsky.social over open access payments?
September 4, 2025 at 11:44 PM
Has anyone else had experience with being harassed by @elsevierconnect.bsky.social over open access payments?
Reposted by Jon Mellon
The lovely people @britishelectionstudy.com released the random probaility data which means we can begin to unravel some unanswered questions about turnout in 2024.
A substack to follow but a starter of social class and vote/non-vote. Which party represents the working class? None of the above.
A substack to follow but a starter of social class and vote/non-vote. Which party represents the working class? None of the above.
August 29, 2025 at 4:45 PM
The lovely people @britishelectionstudy.com released the random probaility data which means we can begin to unravel some unanswered questions about turnout in 2024.
A substack to follow but a starter of social class and vote/non-vote. Which party represents the working class? None of the above.
A substack to follow but a starter of social class and vote/non-vote. Which party represents the working class? None of the above.
Reposted by Jon Mellon
5. Today I read a paper by @sabinaleonelli.bsky.social and Alexander Mussgnug that I think illustrates this point perfectly.
philsci-archive.pitt.edu/24891/1/Phil...
philsci-archive.pitt.edu/24891/1/Phil...
August 19, 2025 at 5:11 AM
5. Today I read a paper by @sabinaleonelli.bsky.social and Alexander Mussgnug that I think illustrates this point perfectly.
philsci-archive.pitt.edu/24891/1/Phil...
philsci-archive.pitt.edu/24891/1/Phil...
Does anyone have a good reference for the theory that the polls overestimated remain in 2016 because of a lack of education weighting? I've heard this theory but not sure if anyone ever fleshed it out in writing
August 14, 2025 at 1:44 PM
Does anyone have a good reference for the theory that the polls overestimated remain in 2016 because of a lack of education weighting? I've heard this theory but not sure if anyone ever fleshed it out in writing
can anyone see a downside to the plan of ordering this desktop specifically for the narrow set of workflows where I have really high RAM requirements and using a modern Macbook pro for every thing else?
August 14, 2025 at 12:51 AM
can anyone see a downside to the plan of ordering this desktop specifically for the narrow set of workflows where I have really high RAM requirements and using a modern Macbook pro for every thing else?
Has anyone written a paper on the ideology/partisanship of pollsters?
August 13, 2025 at 4:04 PM
Has anyone written a paper on the ideology/partisanship of pollsters?
Reposted by Jon Mellon
I’ve never really understood why they don’t force separate tokens for digits. Unlike words, the individual characters of numbers are always meaningful in a consistent way
August 8, 2025 at 6:42 PM
I’ve never really understood why they don’t force separate tokens for digits. Unlike words, the individual characters of numbers are always meaningful in a consistent way
Yes! I recommend validating LLMs against a task you're actually interested in rather than trying to guess whether these failure modes indicate that it will or won't be capable.
So much this. Letter counting and state names are gimmicks, not primary use cases. Frontier models are already remarkably capable for many quite difficult tasks despite still, of course, failing in important ways. We should be able to recognize this fact without uncritically accepting industry hype.
One of the really cursed things about AI discourse is that people try to argue it isn’t USEFUL FOR CERTAIN TASKS and then pretend that’s the same as arguing it’s all smoke and mirrors. A screwdriver is more useful for many things than a jet plane, but a jet plane is an impressive piece of tech.
August 8, 2025 at 1:54 PM
Yes! I recommend validating LLMs against a task you're actually interested in rather than trying to guess whether these failure modes indicate that it will or won't be capable.
The one grammar rule I refuse to follow is putting a full stop within a quotation rather than after it. It just feels like misquoting the original source (it changes the meaning of the original by implying the sentence ended there).
August 6, 2025 at 12:03 PM
The one grammar rule I refuse to follow is putting a full stop within a quotation rather than after it. It just feels like misquoting the original source (it changes the meaning of the original by implying the sentence ended there).
Reposted by Jon Mellon
PSA: Just trotting out the aphorism that “all models are wrong, but some are useful” doesn’t mean *your* model is among the latter…
July 31, 2025 at 4:33 PM
PSA: Just trotting out the aphorism that “all models are wrong, but some are useful” doesn’t mean *your* model is among the latter…
Reposted by Jon Mellon
If researchers find Cohen’s d = 8, no they didn’t.
(probably.)
Thoughts on the distribution of Cohen's d values in psychology and why we should think about their plausibility when reading articles.
(probably.)
Thoughts on the distribution of Cohen's d values in psychology and why we should think about their plausibility when reading articles.
If researchers find Cohen's d = 8, no they didn't
I’ve spent a lot of time thinking about the plausibility of standardized effect sizes in the last year. From a trustworthiness assessment perspective, (standardized) effect sizes have a great combinat...
mmmdata.io
July 26, 2025 at 1:36 PM
If researchers find Cohen’s d = 8, no they didn’t.
(probably.)
Thoughts on the distribution of Cohen's d values in psychology and why we should think about their plausibility when reading articles.
(probably.)
Thoughts on the distribution of Cohen's d values in psychology and why we should think about their plausibility when reading articles.
Reposted by Jon Mellon
Extreme heat during the growing season increases the number of undernourished households in the following year, measured by calories, iron, and other nutrients in rural India, from Paul Stainier, Manisha Shah, and Alan Barreca https://www.nber.org/papers/w34047
July 24, 2025 at 1:00 PM
Extreme heat during the growing season increases the number of undernourished households in the following year, measured by calories, iron, and other nutrients in rural India, from Paul Stainier, Manisha Shah, and Alan Barreca https://www.nber.org/papers/w34047