Lightnews — Scholar-powered news

Max Ghenis @maxghenis.bsky.social · 2d

I have some free time Thursday and Friday afternoons - shoot me a message if you'd like to connect in LA. And you can RSVP to the event here:
forms.zohopublic.com/imaginela1/f...

RSVP for Benefit Navigator Convening/Amplifi Launch Event

Date: Friday, October 24, 2025 8:45am-12pm Location: Ebell of Los Angeles, 743 S Lucerne Blvd, Los Angeles, CA 90005, Dining Hall

forms.zohopublic.com

Max Ghenis @maxghenis.bsky.social · 2d

Heading to LA this week for Benefit Navigator's event.

Their platform helps families and case managers navigate public benefits and tax credits - powered by the @us.policyengine.org API for tax and benefit calculations. Excited to see tech and policy come together to expand access.

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Max Ghenis @maxghenis.bsky.social · 4d

Tomorrow evening I'll be celebrating the 13th anniversary of the @opengovhub.bsky.social, @us.policyengine.org's new home in DC. I'll also give a short talk on our work to promote open governance and transparency, the mission of the space and our neighbor organizations. Tickets still available!

13th Anniversary Celebration of the Open Gov Hub

Celebrate 13 years of Open Gov Hub!

www.eventbrite.com

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Max Ghenis @maxghenis.bsky.social · 13d

ChatGPT estimates the anti-Israel boycott against Shouk increased their risk of closure by 40% this year.

Links:
instagram.com/p/DHWA8BWJHl6
washingtonsocialist.mdcdsa.org/ws-articles/...
instagram.com/p/DPUllyAjkxb
chatgpt.com/share/68e223...

Max Ghenis @maxghenis.bsky.social · 13d

Disappointed that the plant-based Shouk, my favorite fast-casual place in DC, has closed. Anti-Israel groups targeted it because an Israeli immigrant owned it, and are now cheering their victory.

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Max Ghenis @maxghenis.bsky.social · 13d

Agentic AI coding tools continue to inspire us to turn everything into software.

Join us at our new home in downtown DC, the @opengovhub.bsky.social, for a celebratory happy hour on Oct 22: luma.com/lnrzph2h

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Max Ghenis @maxghenis.bsky.social · 18d

Alaska's Fairbanks region has the highest second-lowest-cost silver plan (a key PTC ingredient) for older residents.

As a result, a married couple, each 64 years old earning $83k, would gain $57,292 in 2026 if the enhanced subsidies are extended. They'd get some PTC with up to $756k income.

Max Ghenis @maxghenis.bsky.social · 18d

Our new ACA calculator shows how extending the enhanced premium tax credits would affect households.

An extreme case: A 64-year-old in Fairbanks, AK would gain $655 in 2026 if they earn $61k, but gain $26,861 if they earn $62k.

Try it here: policyengine.org/us/aca-calc

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Max Ghenis @maxghenis.bsky.social · 18d

Come by tonight if you're in London!

PolicyEngine UK @uk.policyengine.org · 19d

Economic policy drinks tomorrow in London 🍺

Thursday 6-8pm at The Sherlock Holmes (Northumberland St, near Embankment)

Light bites + first round on PolicyEngine. Come meet economists & policy analysts working on UK tax/benefits/public finance.
luma.com/oz1qt2ec

Economic policy happy hour · Luma

Drinks and discussion for the UK economic policy community. PolicyEngine is hosting an informal happy hour for economists, researchers, and policy analysts…

luma.com

Max Ghenis @maxghenis.bsky.social · 18d

The Prenatal-to-3 Policy Impact Center just launched their new Policy Impact Calculator, which uses @us.policyengine.org for federal and state tax modeling. Great example of research infrastructure enabling better policy decisions for young children and families.
pn3policy.org/policy-impac...

2025 Policy Impact Calculator - Prenatal-to-3 Policy Impact Center

Explore our new interactive calculator to see how wages, paid leave, nutrition programs, child care subsidies, and tax credits shape the financial resources available to families with young children—s...

pn3policy.org

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Max Ghenis @maxghenis.bsky.social · Sep 18

Enjoyed my conversation with the SVIC Podcast about how
@policyengine.org uses Claude Code to democratize economic policy analysis. Watch here: youtu.be/4apWdJR9-iY?...

How A Google Engineer Uses Claude Code At His Startup - Max Ghenis Founder of Policy Engine

YouTube video by SVIC Podcast

youtu.be

Max Ghenis @maxghenis.bsky.social · Sep 13

Can't wait for our first live event in London! If you're in the area and interested in policy simulation, I think you'll discover major new possibilities our new app and research will offer.

See you there: eventbrite.co.uk/e/policyengi...

Max Ghenis @maxghenis.bsky.social · Sep 10

We constructed fully synthetic firm microdata to conduct this analysis. I was struck how calibrating to a large range of coarse aggregates could result in microdata that reveals sharp responses to cliff effects.

You could run a bunching study on this synthetic data! (And we will.)

Max Ghenis @maxghenis.bsky.social · Sep 5

This partnership exemplifies why we built PolicyEngine: policy analysis tools should be open, accessible, and sustainable.

Honored that NBER trusts us to ensure TAXSIM—the foundation of tax research for decades—continues serving researchers while evolving for modern needs.

PolicyEngine US @us.policyengine.org · Sep 5

🤝 Big news: PolicyEngine and @nber.org
have signed an MOU to ensure researchers worldwide continue accessing critical tax microsimulation tools.

We're building an open-source TAXSIM emulator, combining NBER's 50+ years of tax expertise with modern open-source infrastructure.

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Max Ghenis @maxghenis.bsky.social · Aug 30

Here I also used LLMs to check my intuition on how readers might interpret articles (all four I tested interpreted the Telegraph's statement the way I thought the public might; that is, incorrectly).

Max Ghenis @maxghenis.bsky.social · Aug 30

HMRC projected last year that raising the VAT threshold to £90k would increase revenues in 2028-29. Looks weird until you realize that would represent a tax hike by then, since it'd otherwise be £92k!

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Max Ghenis @maxghenis.bsky.social · Aug 30

Today, @telegraphnews.bsky.social suggested that raising the UK VAT registration threshold would increase revenues in the long run. This misread (poorly documented) government projections, which reflected inflation adjustments in the baseline. My latest:
substack.com/home/post/p-...

VAT thresholds, revenues, and the role of counterfactuals

No, the OBR has not projected that raising the VAT threshold would increase tax revenues.

substack.com

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Max Ghenis @maxghenis.bsky.social · Aug 29

Yep github.com/PolicyEngine...

policyengine-us/.claude at master · PolicyEngine/policyengine-us

The PolicyEngine US Python package contains a rules engine of the US tax-benefit system, and microdata generation for microsimulation analysis. - PolicyEngine/policyengine-us

github.com

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Max Ghenis @maxghenis.bsky.social · Aug 28

We have a suite of subsequent checks (separate agents) after test-creator and rules-engineer complete. If they misalign that gives more to interrogate.

We'd like to test our hypothesis here with a controlled experiment, but my guess is that our approach reduces cascading errors.

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Max Ghenis @maxghenis.bsky.social · Aug 28

Tests can be wrong! This way we get two interpretations of the specifications (statutes, regs, manuals), coming from different perspectives. If the agent misinterprets the spec in constructing the test, it's more likely to make the same error at the encoding stage--less so if they're starting fresh.

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Max Ghenis @maxghenis.bsky.social · Aug 28

I see this as the next iteration of test-driven development, free from the biases you can have by writing the code after you've already conceptualized its logic by writing tests. We expect separating the work to improve quality.

Full video here (I started at 4:46): youtu.be/vss_slgfzIg?...

Modeling Texas LIHEAP with AI Sub-Agents | PolicyEngine Demo

YouTube video by PolicyEngine

youtu.be

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Max Ghenis @maxghenis.bsky.social · Aug 28

I've been using Claude Code a LOT lately ($5,800+ in tokens last month on my $200 Claude Max plan), and now experimenting with custom slash commands and subagents. Here's an example: using parallel subagents to independently write integration tests and encode policies for @us.policyengine.org.

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Reposted by Max Ghenis

PolicyEngine US @us.policyengine.org · Aug 22

🎉 PolicyEngine has been awarded a $300,000 Phase I POSE grant from NSF (Award No. 2518372) to expand our open-source platform, build sustainable governance, and grow our contributor community! https://policyengine.org/us/research/nsf-pose-phase-1-grant

National Science Foundation awards PolicyEngine $300,000 grant | PolicyEngine US

NSF's Pathways to Enable Open-Source Ecosystems program will support PolicyEngine's work to expand access to policy analysis tools.

policyengine.org

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Max Ghenis @maxghenis.bsky.social · May 16

Bumping the cap to $62k/124k would benefit 22% of US residents in the top income decile and 1.2% of those in the bottom 90%.

Max Ghenis @maxghenis.bsky.social · May 14

The SALT cap would raise taxes on 22% of Americans in the top income decile, and 3% of Americans in the bottom nine deciles.

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