Istvan Hajnal
@istvanhajnal.bsky.social
Statistics, data science, market research, Elvis Costello, bass,
Ipsos, media research, audience measurement.
Boutersem-Amsterdam
Ipsos, media research, audience measurement.
Boutersem-Amsterdam
Reposted by Istvan Hajnal
Epstein files merch out now!
December 21, 2025 at 12:18 PM
Epstein files merch out now!
Reposted by Istvan Hajnal
How did people in 1913 see the world? Scientists trained LLMs exclusively on pre-1913 texts—no Wikipedia, no 20/20. The model literally doesn't know of WWI. And it reflects spirit of the times without guardrails reflecting modern-day sensitivities.
This is a terrific research application of LLMs.
This is a terrific research application of LLMs.
GitHub - DGoettlich/history-llms: Information hub for our project training the largest possible historical LLMs.
Information hub for our project training the largest possible historical LLMs. - DGoettlich/history-llms
github.com
December 19, 2025 at 8:59 PM
How did people in 1913 see the world? Scientists trained LLMs exclusively on pre-1913 texts—no Wikipedia, no 20/20. The model literally doesn't know of WWI. And it reflects spirit of the times without guardrails reflecting modern-day sensitivities.
This is a terrific research application of LLMs.
This is a terrific research application of LLMs.
December 17, 2025 at 9:19 AM
Reposted by Istvan Hajnal
🚨 SynthNet is out 🚨
Researchers propose new constructs and measures faster than anyone can track. We (@anniria.bsky.social @ruben.the100.ci) built a search engine to check what already exists and help identify redundancies; indexing 74,000 scales from ~31,500 instruments in APA PsycTests. 🧵1/3
Researchers propose new constructs and measures faster than anyone can track. We (@anniria.bsky.social @ruben.the100.ci) built a search engine to check what already exists and help identify redundancies; indexing 74,000 scales from ~31,500 instruments in APA PsycTests. 🧵1/3
November 26, 2025 at 11:42 AM
🚨 SynthNet is out 🚨
Researchers propose new constructs and measures faster than anyone can track. We (@anniria.bsky.social @ruben.the100.ci) built a search engine to check what already exists and help identify redundancies; indexing 74,000 scales from ~31,500 instruments in APA PsycTests. 🧵1/3
Researchers propose new constructs and measures faster than anyone can track. We (@anniria.bsky.social @ruben.the100.ci) built a search engine to check what already exists and help identify redundancies; indexing 74,000 scales from ~31,500 instruments in APA PsycTests. 🧵1/3
Reposted by Istvan Hajnal
#rstats
It is with profound sadness I heard that my long-time friend and colleague, John Fox passed away this week.
He was the author of {car}, {effects}, {Rcmdr}, ... and numerous influential books. I will miss him greatly.
www.john-fox.ca
It is with profound sadness I heard that my long-time friend and colleague, John Fox passed away this week.
He was the author of {car}, {effects}, {Rcmdr}, ... and numerous influential books. I will miss him greatly.
www.john-fox.ca
John Fox: Books and Software
www.john-fox.ca
November 28, 2025 at 3:26 PM
#rstats
It is with profound sadness I heard that my long-time friend and colleague, John Fox passed away this week.
He was the author of {car}, {effects}, {Rcmdr}, ... and numerous influential books. I will miss him greatly.
www.john-fox.ca
It is with profound sadness I heard that my long-time friend and colleague, John Fox passed away this week.
He was the author of {car}, {effects}, {Rcmdr}, ... and numerous influential books. I will miss him greatly.
www.john-fox.ca
Reposted by Istvan Hajnal
When I worked for Obama, I advised him on how to talk to Russian leaders. I never gave the Kremlin advice on how to talk to Obama (and I talked to Ushakov many times!).
November 26, 2025 at 5:33 PM
When I worked for Obama, I advised him on how to talk to Russian leaders. I never gave the Kremlin advice on how to talk to Obama (and I talked to Ushakov many times!).
Reposted by Istvan Hajnal
Because @laurewynants.bsky.social and @benvancalster.bsky.social do no get on here much #DataScience #MachineLearning #MissingData #Imputation #Rstats #Python #AI journals.plos.org/plosone/arti...
November 23, 2025 at 2:08 PM
Because @laurewynants.bsky.social and @benvancalster.bsky.social do no get on here much #DataScience #MachineLearning #MissingData #Imputation #Rstats #Python #AI journals.plos.org/plosone/arti...
Reposted by Istvan Hajnal
Het verbaast me dat journalisten en academici Raoul Hedebouw hiermee gewoon laten wegkomen. In @deafspraaktv mocht Hedebouw, beweren dat “we” twee tot zes keer meer uitgeven aan wapens dan de Russen (zie fragment [link.mp4]) #RaoulHedebouw #PVDA #deafspraak #deafspraakopvrijdag #Rusland /1
November 16, 2025 at 12:09 PM
Het verbaast me dat journalisten en academici Raoul Hedebouw hiermee gewoon laten wegkomen. In @deafspraaktv mocht Hedebouw, beweren dat “we” twee tot zes keer meer uitgeven aan wapens dan de Russen (zie fragment [link.mp4]) #RaoulHedebouw #PVDA #deafspraak #deafspraakopvrijdag #Rusland /1
Het verbaast me dat journalisten en academici Raoul Hedebouw hiermee gewoon laten wegkomen. In @deafspraaktv mocht Hedebouw, beweren dat “we” twee tot zes keer meer uitgeven aan wapens dan de Russen (zie fragment [link.mp4]) #RaoulHedebouw #PVDA #deafspraak #deafspraakopvrijdag #Rusland /1
November 16, 2025 at 12:09 PM
Het verbaast me dat journalisten en academici Raoul Hedebouw hiermee gewoon laten wegkomen. In @deafspraaktv mocht Hedebouw, beweren dat “we” twee tot zes keer meer uitgeven aan wapens dan de Russen (zie fragment [link.mp4]) #RaoulHedebouw #PVDA #deafspraak #deafspraakopvrijdag #Rusland /1
Reposted by Istvan Hajnal
Woo, the post is on Data Elixir! It's a really great data science newsletter if you are looking for one!
dataelixir.com
dataelixir.com
November 12, 2025 at 9:58 PM
Woo, the post is on Data Elixir! It's a really great data science newsletter if you are looking for one!
dataelixir.com
dataelixir.com
I wrote a blogpost on clustering respondents within households, and how you can derive a simple rule of thumb for estimating the effect that has on standard errors.
open.substack.com/pub/istvanha...
#DataScience #Statistics #Survey #Methodology
open.substack.com/pub/istvanha...
#DataScience #Statistics #Survey #Methodology
A Back-of-the-Envelope Calculation of the Effect of Clustering Respondents Within Households on Standard Errors
Imagine you’re in a meeting and need to quickly explain how clustering respondents within households affects the length of a confidence interval, but you don’t have a computer handy.
open.substack.com
November 7, 2025 at 2:31 PM
I wrote a blogpost on clustering respondents within households, and how you can derive a simple rule of thumb for estimating the effect that has on standard errors.
open.substack.com/pub/istvanha...
#DataScience #Statistics #Survey #Methodology
open.substack.com/pub/istvanha...
#DataScience #Statistics #Survey #Methodology
Reposted by Istvan Hajnal
I wrote a short LinkedIn article about the Law of Truely Large Numbers (not to be confused with the law of large numbers), Bart De Wever and Ordinal variables.
Enjoy!
lnkd.in/ehKjiFmS
#DataScience #Politics #BDW #Belgium
Enjoy!
lnkd.in/ehKjiFmS
#DataScience #Politics #BDW #Belgium
October 29, 2025 at 2:31 PM
I wrote a short LinkedIn article about the Law of Truely Large Numbers (not to be confused with the law of large numbers), Bart De Wever and Ordinal variables.
Enjoy!
lnkd.in/ehKjiFmS
#DataScience #Politics #BDW #Belgium
Enjoy!
lnkd.in/ehKjiFmS
#DataScience #Politics #BDW #Belgium
I wrote a short LinkedIn article about the Law of Truely Large Numbers (not to be confused with the law of large numbers), Bart De Wever and Ordinal variables.
Enjoy!
lnkd.in/ehKjiFmS
#DataScience #Politics #BDW #Belgium
Enjoy!
lnkd.in/ehKjiFmS
#DataScience #Politics #BDW #Belgium
October 29, 2025 at 2:31 PM
I wrote a short LinkedIn article about the Law of Truely Large Numbers (not to be confused with the law of large numbers), Bart De Wever and Ordinal variables.
Enjoy!
lnkd.in/ehKjiFmS
#DataScience #Politics #BDW #Belgium
Enjoy!
lnkd.in/ehKjiFmS
#DataScience #Politics #BDW #Belgium
Reposted by Istvan Hajnal
#TodayinHistory #dataviz #OTD 📊
💀Oct 25, 1914 Wilhelm Lexis died in Gottingen, Germany 🇩🇪
1875: The Lexis diagram, showing relations among age (cohort), calendar time, and life spans of individuals simultaneously.
Revolutionized demography, making key variables visible
💀Oct 25, 1914 Wilhelm Lexis died in Gottingen, Germany 🇩🇪
1875: The Lexis diagram, showing relations among age (cohort), calendar time, and life spans of individuals simultaneously.
Revolutionized demography, making key variables visible
October 26, 2025 at 1:36 AM
#TodayinHistory #dataviz #OTD 📊
💀Oct 25, 1914 Wilhelm Lexis died in Gottingen, Germany 🇩🇪
1875: The Lexis diagram, showing relations among age (cohort), calendar time, and life spans of individuals simultaneously.
Revolutionized demography, making key variables visible
💀Oct 25, 1914 Wilhelm Lexis died in Gottingen, Germany 🇩🇪
1875: The Lexis diagram, showing relations among age (cohort), calendar time, and life spans of individuals simultaneously.
Revolutionized demography, making key variables visible
Niet echt verrassend, al maakt deze visualisatie het wel heel zichtbaar: het electoraat van #Ecolo-#Groen en #VlaamsBelang is op leeftijd, inkomensdeciel, cultureel en economisch links-rechts bijna elkaars spiegelbeeld.
#DeStemming #DS2025 #WorkInProgress
#DeStemming #DS2025 #WorkInProgress
October 5, 2025 at 1:16 PM
Niet echt verrassend, al maakt deze visualisatie het wel heel zichtbaar: het electoraat van #Ecolo-#Groen en #VlaamsBelang is op leeftijd, inkomensdeciel, cultureel en economisch links-rechts bijna elkaars spiegelbeeld.
#DeStemming #DS2025 #WorkInProgress
#DeStemming #DS2025 #WorkInProgress
There seems to be no effect of age on perceived suitability of Bart De Wever as Prime Minister in function of age, until about 50, after that there's a strong positive effect (this is a 0-10 point scale).
#DeStemming #BartDeWever #DataScience #WorkInProgress
#DeStemming #BartDeWever #DataScience #WorkInProgress
October 4, 2025 at 3:43 PM
There seems to be no effect of age on perceived suitability of Bart De Wever as Prime Minister in function of age, until about 50, after that there's a strong positive effect (this is a 0-10 point scale).
#DeStemming #BartDeWever #DataScience #WorkInProgress
#DeStemming #BartDeWever #DataScience #WorkInProgress
Reposted by Istvan Hajnal
I have lived and worked in and around Chicago for 27 years and I have been assaulted less often than Sen Paul has been in his own back yard.
September 28, 2025 at 8:26 PM
I have lived and worked in and around Chicago for 27 years and I have been assaulted less often than Sen Paul has been in his own back yard.
Ben geen grote fan van De Wever, maar een zwak leider is hij allerminst. Mijn sympathie voor hem stijgt zowaar.
#DeWever #Netanyahu #Israel #Gaza
#DeWever #Netanyahu #Israel #Gaza
September 3, 2025 at 3:20 PM
Ben geen grote fan van De Wever, maar een zwak leider is hij allerminst. Mijn sympathie voor hem stijgt zowaar.
#DeWever #Netanyahu #Israel #Gaza
#DeWever #Netanyahu #Israel #Gaza
Reposted by Istvan Hajnal
I have a slide about an unusual data request I once got: can we show that song choruses are appearing earlier due to the economics of streaming (gotta hook people in early to get paid)? I joked that it's not as if anyone's got a database of song structures. But it turns out that someone has...
August 17, 2025 at 1:37 PM
I have a slide about an unusual data request I once got: can we show that song choruses are appearing earlier due to the economics of streaming (gotta hook people in early to get paid)? I joked that it's not as if anyone's got a database of song structures. But it turns out that someone has...
1/
An optimist and a pessimist walk into a bar... and get roped into a 3-question quiz by a statistician. Closest guesses to the truth win.
#datascience #statistics #rstats #mrx #stein #shrinkage
An optimist and a pessimist walk into a bar... and get roped into a 3-question quiz by a statistician. Closest guesses to the truth win.
#datascience #statistics #rstats #mrx #stein #shrinkage
July 28, 2025 at 10:41 AM
1/
An optimist and a pessimist walk into a bar... and get roped into a 3-question quiz by a statistician. Closest guesses to the truth win.
#datascience #statistics #rstats #mrx #stein #shrinkage
An optimist and a pessimist walk into a bar... and get roped into a 3-question quiz by a statistician. Closest guesses to the truth win.
#datascience #statistics #rstats #mrx #stein #shrinkage
Reposted by Istvan Hajnal
1/
Een optimist en een pessimist gaan naar een café ... en worden door een statisticus uitgenodigd voor een 3 vragen tellende quiz. Wie het dichtst bij het juiste antwoord zit, wint.
#datascience #statistiek
Een optimist en een pessimist gaan naar een café ... en worden door een statisticus uitgenodigd voor een 3 vragen tellende quiz. Wie het dichtst bij het juiste antwoord zit, wint.
#datascience #statistiek
July 25, 2025 at 2:11 PM
1/
Een optimist en een pessimist gaan naar een café ... en worden door een statisticus uitgenodigd voor een 3 vragen tellende quiz. Wie het dichtst bij het juiste antwoord zit, wint.
#datascience #statistiek
Een optimist en een pessimist gaan naar een café ... en worden door een statisticus uitgenodigd voor een 3 vragen tellende quiz. Wie het dichtst bij het juiste antwoord zit, wint.
#datascience #statistiek
1/
Een optimist en een pessimist gaan naar een café ... en worden door een statisticus uitgenodigd voor een 3 vragen tellende quiz. Wie het dichtst bij het juiste antwoord zit, wint.
#datascience #statistiek
Een optimist en een pessimist gaan naar een café ... en worden door een statisticus uitgenodigd voor een 3 vragen tellende quiz. Wie het dichtst bij het juiste antwoord zit, wint.
#datascience #statistiek
July 25, 2025 at 2:11 PM
1/
Een optimist en een pessimist gaan naar een café ... en worden door een statisticus uitgenodigd voor een 3 vragen tellende quiz. Wie het dichtst bij het juiste antwoord zit, wint.
#datascience #statistiek
Een optimist en een pessimist gaan naar een café ... en worden door een statisticus uitgenodigd voor een 3 vragen tellende quiz. Wie het dichtst bij het juiste antwoord zit, wint.
#datascience #statistiek
Reposted by Istvan Hajnal
My latest blogpost on #substack: istvanhajnal.substack.com/p/the-kalman...
#datascience #mrx #kalmanfilters #statistics #rstats
#datascience #mrx #kalmanfilters #statistics #rstats
The Kalman Filter, Lizards, and Market Research
Imagine you’re a biologist studying the movement of desert lizards.
istvanhajnal.substack.com
July 19, 2025 at 6:35 PM
My latest blogpost on #substack: istvanhajnal.substack.com/p/the-kalman...
#datascience #mrx #kalmanfilters #statistics #rstats
#datascience #mrx #kalmanfilters #statistics #rstats