Jason Hartline
@jasonhartline.bsky.social
Professor at Northwestern CS. Economics, by courtesy. Study mechanism design, economics of algorithms, regulation of algorithms, AI and society. https://sites.northwestern.edu/hartline/
Hello @chicagocta.bsky.social, for several days at least, the CTA train tracker is not showing the northbound purple line at Wilson. (These are usually above the red line in the attached screenshot.) www.transitchicago.com/traintracker...
November 6, 2025 at 3:19 PM
Hello @chicagocta.bsky.social, for several days at least, the CTA train tracker is not showing the northbound purple line at Wilson. (These are usually above the red line in the attached screenshot.) www.transitchicago.com/traintracker...
I wasn't expecting this!
October 20, 2025 at 8:30 PM
I wasn't expecting this!
Thanks to Kangning Wang for working with me on this
"A Geometric Analysis of Gains from Trade".
There is a very simple geometric proof that the "random proposer" mechanism gives a 4-approximation to first-best gains from trade. And some calculus gives the state-of-the-art 3.15-approximation.
"A Geometric Analysis of Gains from Trade".
There is a very simple geometric proof that the "random proposer" mechanism gives a 4-approximation to first-best gains from trade. And some calculus gives the state-of-the-art 3.15-approximation.
August 15, 2025 at 11:38 PM
Thanks to Kangning Wang for working with me on this
"A Geometric Analysis of Gains from Trade".
There is a very simple geometric proof that the "random proposer" mechanism gives a 4-approximation to first-best gains from trade. And some calculus gives the state-of-the-art 3.15-approximation.
"A Geometric Analysis of Gains from Trade".
There is a very simple geometric proof that the "random proposer" mechanism gives a 4-approximation to first-best gains from trade. And some calculus gives the state-of-the-art 3.15-approximation.
Congratulations Dr. Paula Kayongo for successfully defending her Ph.D. dissertation!
"Behavioral Information Design for Forecasting Dashboards: Equilibria, Mechanisms, and Calibration"
Thanks to her stellar committee: @jessicahullman.bsky.social, @mjskay.com, and Annie Liang!
"Behavioral Information Design for Forecasting Dashboards: Equilibria, Mechanisms, and Calibration"
Thanks to her stellar committee: @jessicahullman.bsky.social, @mjskay.com, and Annie Liang!
August 1, 2025 at 7:58 PM
Congratulations Dr. Paula Kayongo for successfully defending her Ph.D. dissertation!
"Behavioral Information Design for Forecasting Dashboards: Equilibria, Mechanisms, and Calibration"
Thanks to her stellar committee: @jessicahullman.bsky.social, @mjskay.com, and Annie Liang!
"Behavioral Information Design for Forecasting Dashboards: Equilibria, Mechanisms, and Calibration"
Thanks to her stellar committee: @jessicahullman.bsky.social, @mjskay.com, and Annie Liang!
It was wonderful, but not easy, to try to keep up with the many projects that have gone into your formulation of Trustworthy AI, @yifanwu.bsky.social. Thanks for being patient and teaching me so much!
July 29, 2025 at 7:56 PM
It was wonderful, but not easy, to try to keep up with the many projects that have gone into your formulation of Trustworthy AI, @yifanwu.bsky.social. Thanks for being patient and teaching me so much!
Congratulations to Dr. @yifanwu.bsky.social for successfully defending her Ph.D. dissertation!
"Trustworthy AI: Foundations from Proper Scoring Rules"
Thanks to her committee: @jessicahullman.bsky.social, Bobby Kleinberg, and Annie Liang.
"Trustworthy AI: Foundations from Proper Scoring Rules"
Thanks to her committee: @jessicahullman.bsky.social, Bobby Kleinberg, and Annie Liang.
July 29, 2025 at 7:49 PM
Congratulations to Dr. @yifanwu.bsky.social for successfully defending her Ph.D. dissertation!
"Trustworthy AI: Foundations from Proper Scoring Rules"
Thanks to her committee: @jessicahullman.bsky.social, Bobby Kleinberg, and Annie Liang.
"Trustworthy AI: Foundations from Proper Scoring Rules"
Thanks to her committee: @jessicahullman.bsky.social, Bobby Kleinberg, and Annie Liang.
Dashboards are visualizations of uncertainty. We compared:
1. allocation rules (probability of winning as function of bid).
2. (hypothetical) utility curves (for selected values, as function of bid).
3. heatmap (showing utility on a grid of bid,value pairs).
Each are depicted in this figure.
1. allocation rules (probability of winning as function of bid).
2. (hypothetical) utility curves (for selected values, as function of bid).
3. heatmap (showing utility on a grid of bid,value pairs).
Each are depicted in this figure.
July 29, 2025 at 1:04 PM
Dashboards are visualizations of uncertainty. We compared:
1. allocation rules (probability of winning as function of bid).
2. (hypothetical) utility curves (for selected values, as function of bid).
3. heatmap (showing utility on a grid of bid,value pairs).
Each are depicted in this figure.
1. allocation rules (probability of winning as function of bid).
2. (hypothetical) utility curves (for selected values, as function of bid).
3. heatmap (showing utility on a grid of bid,value pairs).
Each are depicted in this figure.
The Serpentine at Chefs Special Cocktail Bar in Chicago is one of the best cocktails in the city. Got my grades in. Hello summer!
June 17, 2025 at 3:53 AM
The Serpentine at Chefs Special Cocktail Bar in Chicago is one of the best cocktails in the city. Got my grades in. Hello summer!
America is DEI. #NoKingsDay, Chicago.
June 14, 2025 at 10:34 PM
America is DEI. #NoKingsDay, Chicago.
Once upon a time, five years ago, before BlueSky, I wrote the LaTeX code to to make a one-line Beamer block. Reposting.
www.overleaf.com/read/whygfgw...
www.overleaf.com/read/whygfgw...
June 11, 2025 at 7:42 PM
Once upon a time, five years ago, before BlueSky, I wrote the LaTeX code to to make a one-line Beamer block. Reposting.
www.overleaf.com/read/whygfgw...
www.overleaf.com/read/whygfgw...
Here is my receipt for a Divvy scooter ride where I parked right next to a full station. Why is it costing me 50% more when a Divvy station is full? That's the wrong incentive for me and for Divvy (to keep the stations free).
June 9, 2025 at 2:35 PM
Here is my receipt for a Divvy scooter ride where I parked right next to a full station. Why is it costing me 50% more when a Divvy station is full? That's the wrong incentive for me and for Divvy (to keep the stations free).
Here is an essay titled "Frustrated with Oranges" by CharGPT. For the best experience, click the link and have ChatGPT read it out loud. chatgpt.com/share/67a8ef...
February 9, 2025 at 6:14 PM
Here is an essay titled "Frustrated with Oranges" by CharGPT. For the best experience, click the link and have ChatGPT read it out loud. chatgpt.com/share/67a8ef...
A bonus from visiting Morocco in January is surfing! (When the technical program allows.)
February 4, 2025 at 10:26 PM
A bonus from visiting Morocco in January is surfing! (When the technical program allows.)
Had a great visit to @mcgt-um6p.bsky.social this January. Co-organizing a winter school on "Data Economics". Teaching half of my PhD "Mechanism Design" class to their first cohort of PhD students. Closed out the visit with this seminar on "Regulation of Algorithmic Collusion" (video below).
February 4, 2025 at 10:23 PM
Had a great visit to @mcgt-um6p.bsky.social this January. Co-organizing a winter school on "Data Economics". Teaching half of my PhD "Mechanism Design" class to their first cohort of PhD students. Closed out the visit with this seminar on "Regulation of Algorithmic Collusion" (video below).
Last Friday at @mcgt-um6p.bsky.social's Winter School on Data Economics!!
January 29, 2025 at 5:10 PM
Last Friday at @mcgt-um6p.bsky.social's Winter School on Data Economics!!
Thursday at @mcgt-um6p.bsky.social's winter school on Data Economics!
January 27, 2025 at 5:48 PM
Thursday at @mcgt-um6p.bsky.social's winter school on Data Economics!
Wednesday at @mcgt-um6p.bsky.social's winter school on Data Economics!
January 25, 2025 at 7:03 PM
Wednesday at @mcgt-um6p.bsky.social's winter school on Data Economics!
Tea to the left of me,
Coffee to the right,
Here I am, stuck on a peer review.
Coffee to the right,
Here I am, stuck on a peer review.
January 2, 2025 at 10:36 AM
Tea to the left of me,
Coffee to the right,
Here I am, stuck on a peer review.
Coffee to the right,
Here I am, stuck on a peer review.
Recently reminded of this Stephen Hawking quote about the quest for the grand unified theory. I used to teach it in the first lecture of my CS 101 class. Conveniently, my copy of "A Brief History of Time" opens to the page (12).
"Now, if you believe that the universe is not arbitrary, but ..."
"Now, if you believe that the universe is not arbitrary, but ..."
December 14, 2024 at 4:31 PM
Recently reminded of this Stephen Hawking quote about the quest for the grand unified theory. I used to teach it in the first lecture of my CS 101 class. Conveniently, my copy of "A Brief History of Time" opens to the page (12).
"Now, if you believe that the universe is not arbitrary, but ..."
"Now, if you believe that the universe is not arbitrary, but ..."
"less busy than usual" or "closed for thanksgiving"?
November 29, 2024 at 4:09 AM
"less busy than usual" or "closed for thanksgiving"?
Here Google Maps, let me ChatGPT that for you?
December 3, 2023 at 8:36 PM
Here Google Maps, let me ChatGPT that for you?
I love these suggestions for how I should reply to the automated message that my flight is ready to board. I'm so excited!
December 3, 2023 at 7:30 PM
I love these suggestions for how I should reply to the automated message that my flight is ready to board. I'm so excited!
It's easier to earn elbow patches than it is to install them.
November 26, 2023 at 8:08 PM
It's easier to earn elbow patches than it is to install them.