@tommijohnsen.bsky.social
Financial sentiment models don’t fail because they lack confidence.
They fail because confidence can’t detect attribution errors.
The most dangerous mistakes happen when models are most sure.
Target-aware sentiment, structure-first reasoning:
open.substack.com/pub/tommijoh...
They fail because confidence can’t detect attribution errors.
The most dangerous mistakes happen when models are most sure.
Target-aware sentiment, structure-first reasoning:
open.substack.com/pub/tommijoh...
January 29, 2026 at 11:51 AM
Financial sentiment models don’t fail because they lack confidence.
They fail because confidence can’t detect attribution errors.
The most dangerous mistakes happen when models are most sure.
Target-aware sentiment, structure-first reasoning:
open.substack.com/pub/tommijoh...
They fail because confidence can’t detect attribution errors.
The most dangerous mistakes happen when models are most sure.
Target-aware sentiment, structure-first reasoning:
open.substack.com/pub/tommijoh...
A concept I can’t stop thinking about: dimensional arbitrage.
The edge isn’t inside the model’s box — it’s in what the dominant systems underweight (fat tails, breaks, discontinuities).
open.substack.com/pub/tommijoh...
The edge isn’t inside the model’s box — it’s in what the dominant systems underweight (fat tails, breaks, discontinuities).
open.substack.com/pub/tommijoh...
The Age of AI Attractor Markets: One Possible Trajectory
Coauthor: Svetlana Shasharina, PhD
open.substack.com
January 24, 2026 at 1:14 PM
A concept I can’t stop thinking about: dimensional arbitrage.
The edge isn’t inside the model’s box — it’s in what the dominant systems underweight (fat tails, breaks, discontinuities).
open.substack.com/pub/tommijoh...
The edge isn’t inside the model’s box — it’s in what the dominant systems underweight (fat tails, breaks, discontinuities).
open.substack.com/pub/tommijoh...
AI is no longer “experimental” in finance — it’s reading filings, calls, headlines, and social chatter at scale.
This isn’t theory — it’s how markets are actually moving now.
open.substack.com/pub/tommijoh...
This isn’t theory — it’s how markets are actually moving now.
open.substack.com/pub/tommijoh...
AI is no longer an experimental “tool” in finance.
Co-author: Svetlana Shasharina, PhD
open.substack.com
January 20, 2026 at 11:07 AM
AI is no longer “experimental” in finance — it’s reading filings, calls, headlines, and social chatter at scale.
This isn’t theory — it’s how markets are actually moving now.
open.substack.com/pub/tommijoh...
This isn’t theory — it’s how markets are actually moving now.
open.substack.com/pub/tommijoh...
Sentiment analysis is everywhere in investing, but it rests on a quiet assumption: that models correctly attribute sentiment to the target company.
I tested that assumption with an adversarial NVIDIA experiment.
The results were not encouraging.
Full write-up:
open.substack.com/pub/tommijoh...
I tested that assumption with an adversarial NVIDIA experiment.
The results were not encouraging.
Full write-up:
open.substack.com/pub/tommijoh...
What Investors Should Know About Common Sentiment Models: Tone Isn’t Attribution
Sentiment analysis has become a foundational tool in modern investing.
open.substack.com
January 14, 2026 at 2:05 PM
Sentiment analysis is everywhere in investing, but it rests on a quiet assumption: that models correctly attribute sentiment to the target company.
I tested that assumption with an adversarial NVIDIA experiment.
The results were not encouraging.
Full write-up:
open.substack.com/pub/tommijoh...
I tested that assumption with an adversarial NVIDIA experiment.
The results were not encouraging.
Full write-up:
open.substack.com/pub/tommijoh...
Two people hear Jerome Powell speak.
One writes a story.
One updates a model.
The second one moves markets.
👉 open.substack.com/pub/tommijoh...
One writes a story.
One updates a model.
The second one moves markets.
👉 open.substack.com/pub/tommijoh...
Two Ways of Hearing Chairman Jerome Powell: Human News and AI News
And Why I’m Thinking About This Now
open.substack.com
January 7, 2026 at 12:03 PM
Two people hear Jerome Powell speak.
One writes a story.
One updates a model.
The second one moves markets.
👉 open.substack.com/pub/tommijoh...
One writes a story.
One updates a model.
The second one moves markets.
👉 open.substack.com/pub/tommijoh...
New research: traditional sentiment models read tone, not targeted investment intent. Synthetic data shows where models actually break 👇
🔗 open.substack.com/pub/tommijoh...
🔗 open.substack.com/pub/tommijoh...
Dissecting Sentiment into Targeted Financial Signals
What synthetic data reveals about real behavior of common sentiment models
open.substack.com
December 29, 2025 at 12:56 PM
New research: traditional sentiment models read tone, not targeted investment intent. Synthetic data shows where models actually break 👇
🔗 open.substack.com/pub/tommijoh...
🔗 open.substack.com/pub/tommijoh...
AI doesn’t know the future.
It notices tone shifts before prices finish reacting.
open.substack.com/pub/tommijoh...
It notices tone shifts before prices finish reacting.
open.substack.com/pub/tommijoh...
Gen-AI’s Predictive Edge (Or: How Machines Learned to Read What We Can’t)
Coauthored by Tommi Johnsen and Sveta Shasharina
open.substack.com
December 24, 2025 at 2:47 PM
AI doesn’t know the future.
It notices tone shifts before prices finish reacting.
open.substack.com/pub/tommijoh...
It notices tone shifts before prices finish reacting.
open.substack.com/pub/tommijoh...
Markets price narratives faster than humans can read them.
The question isn’t if sentiment matters it’s how to measure it correctly.
🔗https://open.substack.com/pub/tommijohnsen/p/th-market-reads-the-news-do-you?r=5jnw1h&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true
The question isn’t if sentiment matters it’s how to measure it correctly.
🔗https://open.substack.com/pub/tommijohnsen/p/th-market-reads-the-news-do-you?r=5jnw1h&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true
December 16, 2025 at 1:17 PM
Markets price narratives faster than humans can read them.
The question isn’t if sentiment matters it’s how to measure it correctly.
🔗https://open.substack.com/pub/tommijohnsen/p/th-market-reads-the-news-do-you?r=5jnw1h&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true
The question isn’t if sentiment matters it’s how to measure it correctly.
🔗https://open.substack.com/pub/tommijohnsen/p/th-market-reads-the-news-do-you?r=5jnw1h&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true
The real risk right now isn’t inflation it’s complacency about the labor market
Headline payrolls mask weakening trends, rising layoff chatter and slowing momentum beneath the surface
That’s why the Fed’s post-December path is far from clear
open.substack.com/pub/tommijoh...
Headline payrolls mask weakening trends, rising layoff chatter and slowing momentum beneath the surface
That’s why the Fed’s post-December path is far from clear
open.substack.com/pub/tommijoh...
December 13, 2025 at 12:20 PM
The real risk right now isn’t inflation it’s complacency about the labor market
Headline payrolls mask weakening trends, rising layoff chatter and slowing momentum beneath the surface
That’s why the Fed’s post-December path is far from clear
open.substack.com/pub/tommijoh...
Headline payrolls mask weakening trends, rising layoff chatter and slowing momentum beneath the surface
That’s why the Fed’s post-December path is far from clear
open.substack.com/pub/tommijoh...
The December Fed rate cut isn’t a prediction — it’s basically a spoiler.
Cooling labor + no incoming data = decision made.
Full breakdown → open.substack.com/pub/tommijoh...
Cooling labor + no incoming data = decision made.
Full breakdown → open.substack.com/pub/tommijoh...
Will the Fed cut rates in December?
Yes. I think it’s baked in.Thanks for reading!
open.substack.com
December 2, 2025 at 2:42 PM
The December Fed rate cut isn’t a prediction — it’s basically a spoiler.
Cooling labor + no incoming data = decision made.
Full breakdown → open.substack.com/pub/tommijoh...
Cooling labor + no incoming data = decision made.
Full breakdown → open.substack.com/pub/tommijoh...
Hot take: The real AI bubble isn’t Nvidia.
It’s the Application layer no one is paying attention to.
Receipts inside → tommijohnsen.substack.com/p/applicatio...
It’s the Application layer no one is paying attention to.
Receipts inside → tommijohnsen.substack.com/p/applicatio...
Applications firms harvest AI from Platforms into an end-user value.
But are they overpriced?
tommijohnsen.substack.com
November 21, 2025 at 9:30 PM
Hot take: The real AI bubble isn’t Nvidia.
It’s the Application layer no one is paying attention to.
Receipts inside → tommijohnsen.substack.com/p/applicatio...
It’s the Application layer no one is paying attention to.
Receipts inside → tommijohnsen.substack.com/p/applicatio...
AI’s platform layer might already be overpriced — some shockingly so. Heatmap + odds here 👉 open.substack.com/pub/tommijoh...
Analyzing the Platforms!
If we accept that the muscle of AI is Infrastructure, then the Platform layer must be the brain and the most likely place for the next AI winner to emerge: model developers, data clouds, and orchestra...
open.substack.com
November 17, 2025 at 8:08 PM
AI’s platform layer might already be overpriced — some shockingly so. Heatmap + odds here 👉 open.substack.com/pub/tommijoh...
AI isn’t a monolith. It’s a layered economy.
Cash starts in infrastructure, then moves up the stack.
My latest post shows where value is landing & includes a heatmap of AI infra names that may be pricing in too much optimism.
Read here: open.substack.com/pub/tommijoh...
Cash starts in infrastructure, then moves up the stack.
My latest post shows where value is landing & includes a heatmap of AI infra names that may be pricing in too much optimism.
Read here: open.substack.com/pub/tommijoh...
Analyzing AI firms
Why Think in Layers?
open.substack.com
November 14, 2025 at 5:19 PM
AI isn’t a monolith. It’s a layered economy.
Cash starts in infrastructure, then moves up the stack.
My latest post shows where value is landing & includes a heatmap of AI infra names that may be pricing in too much optimism.
Read here: open.substack.com/pub/tommijoh...
Cash starts in infrastructure, then moves up the stack.
My latest post shows where value is landing & includes a heatmap of AI infra names that may be pricing in too much optimism.
Read here: open.substack.com/pub/tommijoh...
The AI market is 3 stories tall: Infrastructure → Platform → Application.
I map leaders, risks (power + leverage), and where value flows next.
Full guide: open.substack.com/pub/tommijoh...
I map leaders, risks (power + leverage), and where value flows next.
Full guide: open.substack.com/pub/tommijoh...
November 3, 2025 at 7:09 PM
The AI market is 3 stories tall: Infrastructure → Platform → Application.
I map leaders, risks (power + leverage), and where value flows next.
Full guide: open.substack.com/pub/tommijoh...
I map leaders, risks (power + leverage), and where value flows next.
Full guide: open.substack.com/pub/tommijoh...
AI: Boom or Bubble?
Goldman Sachs says we’re not in bubble territory—yet.
But private vs. public valuations are diverging, firms are investing in each other, and leverage is through the roof.
Innovation—or inflation by another name?
👉 Read my breakdown: open.substack.com/pub/tommijoh...
Goldman Sachs says we’re not in bubble territory—yet.
But private vs. public valuations are diverging, firms are investing in each other, and leverage is through the roof.
Innovation—or inflation by another name?
👉 Read my breakdown: open.substack.com/pub/tommijoh...
AI: Is it an Overheated Bubble, the Beginning of a Boom, or Both?
The answer is unsatisfying (Goldman Sachs, Oct 22, 2025) as most analysts stop short of the bubble label.
open.substack.com
October 29, 2025 at 12:32 PM
AI: Boom or Bubble?
Goldman Sachs says we’re not in bubble territory—yet.
But private vs. public valuations are diverging, firms are investing in each other, and leverage is through the roof.
Innovation—or inflation by another name?
👉 Read my breakdown: open.substack.com/pub/tommijoh...
Goldman Sachs says we’re not in bubble territory—yet.
But private vs. public valuations are diverging, firms are investing in each other, and leverage is through the roof.
Innovation—or inflation by another name?
👉 Read my breakdown: open.substack.com/pub/tommijoh...
Rare earths aren’t rare — just hard to find in useful form.
These 17 metals power our modern world—from magnets in phones to turbines and EVs. Few understand their history or why they became so geopolitically charged.
My latest Substack:
🔗 open.substack.com/pub/tommijoh...
These 17 metals power our modern world—from magnets in phones to turbines and EVs. Few understand their history or why they became so geopolitically charged.
My latest Substack:
🔗 open.substack.com/pub/tommijoh...
What Exactly Are Rare Earth Elements Anyway?
The term “rare earth” is a misnomer, held over from an era when chemists laboriously extracted tiny amounts from exotic ores.
open.substack.com
October 22, 2025 at 12:46 PM
Rare earths aren’t rare — just hard to find in useful form.
These 17 metals power our modern world—from magnets in phones to turbines and EVs. Few understand their history or why they became so geopolitically charged.
My latest Substack:
🔗 open.substack.com/pub/tommijoh...
These 17 metals power our modern world—from magnets in phones to turbines and EVs. Few understand their history or why they became so geopolitically charged.
My latest Substack:
🔗 open.substack.com/pub/tommijoh...
“The price is the prediction.”
A new era of finance is emerging powered by blockchain, stablecoins, and crowd intelligence.
The Wisdom of Crowds, Rebooted → open.substack.com/pub/tommijoh...
A new era of finance is emerging powered by blockchain, stablecoins, and crowd intelligence.
The Wisdom of Crowds, Rebooted → open.substack.com/pub/tommijoh...
The Wisdom of Crowds, Rebooted as Prediction Markets
Markets have always priced risk.
open.substack.com
October 13, 2025 at 12:44 PM
“The price is the prediction.”
A new era of finance is emerging powered by blockchain, stablecoins, and crowd intelligence.
The Wisdom of Crowds, Rebooted → open.substack.com/pub/tommijoh...
A new era of finance is emerging powered by blockchain, stablecoins, and crowd intelligence.
The Wisdom of Crowds, Rebooted → open.substack.com/pub/tommijoh...
How long will the shutdown last?
Markets: 85% odds ≥10 days; ~50/50 beyond Oct 15.
Here’s how it could skew CPI/BLS data and what to watch next:https://open.substack.com/pub/tommijohnsen/p/how-long-will-the-government-shutdown?r=5jnw1h&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true
Markets: 85% odds ≥10 days; ~50/50 beyond Oct 15.
Here’s how it could skew CPI/BLS data and what to watch next:https://open.substack.com/pub/tommijohnsen/p/how-long-will-the-government-shutdown?r=5jnw1h&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true
October 8, 2025 at 3:15 PM
How long will the shutdown last?
Markets: 85% odds ≥10 days; ~50/50 beyond Oct 15.
Here’s how it could skew CPI/BLS data and what to watch next:https://open.substack.com/pub/tommijohnsen/p/how-long-will-the-government-shutdown?r=5jnw1h&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true
Markets: 85% odds ≥10 days; ~50/50 beyond Oct 15.
Here’s how it could skew CPI/BLS data and what to watch next:https://open.substack.com/pub/tommijohnsen/p/how-long-will-the-government-shutdown?r=5jnw1h&utm_campaign=post&utm_medium=web&showWelcomeOnShare=true
🚨 900,000 jobs—gone. Overnight.
Not a recession. Not outsourcing.
A statistical error.
If our economic data is this fragile, what else don’t we know?
👉 open.substack.com/pub/tommijoh...
Not a recession. Not outsourcing.
A statistical error.
If our economic data is this fragile, what else don’t we know?
👉 open.substack.com/pub/tommijoh...
When 900,000 Jobs Vanish Overnight
The U.S.
open.substack.com
October 3, 2025 at 3:33 PM
🚨 900,000 jobs—gone. Overnight.
Not a recession. Not outsourcing.
A statistical error.
If our economic data is this fragile, what else don’t we know?
👉 open.substack.com/pub/tommijoh...
Not a recession. Not outsourcing.
A statistical error.
If our economic data is this fragile, what else don’t we know?
👉 open.substack.com/pub/tommijoh...
Shutdown headlines scream crisis. Markets usually shrug. Bonds sink, stocks recover, dollar stays weak. Will 2025 be the exception? open.substack.com/pub/tommijoh...
How Government Shutdowns Affect Financial Markets
Government shutdowns regularly capture headlines, but their market impact has historically been limited.
open.substack.com
October 1, 2025 at 2:14 PM
Shutdown headlines scream crisis. Markets usually shrug. Bonds sink, stocks recover, dollar stays weak. Will 2025 be the exception? open.substack.com/pub/tommijoh...
Rate cuts aren’t always the relief investors hope for.
Historically, they’ve arrived after markets peak—right before recessions in most cycles.
Exceptions are rare.
Full analysis + strategy playbook here: open.substack.com/pub/tommijoh...
Historically, they’ve arrived after markets peak—right before recessions in most cycles.
Exceptions are rare.
Full analysis + strategy playbook here: open.substack.com/pub/tommijoh...
Late-Cycle Signals: How Fed Timing and Market Peaks Align
Looking at past Federal Reserve cycles, rate cuts have typically come late in the game.
open.substack.com
September 24, 2025 at 12:30 PM
Rate cuts aren’t always the relief investors hope for.
Historically, they’ve arrived after markets peak—right before recessions in most cycles.
Exceptions are rare.
Full analysis + strategy playbook here: open.substack.com/pub/tommijoh...
Historically, they’ve arrived after markets peak—right before recessions in most cycles.
Exceptions are rare.
Full analysis + strategy playbook here: open.substack.com/pub/tommijoh...
Ever wonder if factor investing has a seasonal rhythm?
Turns out it does — Value shines in January, Growth pops in June, Quality closes the year strong. Timing these beats standing still.
I unpack the patterns + heatmap here:
👉 open.substack.com/pub/tommijoh...
Turns out it does — Value shines in January, Growth pops in June, Quality closes the year strong. Timing these beats standing still.
I unpack the patterns + heatmap here:
👉 open.substack.com/pub/tommijoh...
Factor Seasonality Unpacked: Timing factors beats standing still
Most investors know about the “January Effect”.
open.substack.com
September 11, 2025 at 12:27 PM
Ever wonder if factor investing has a seasonal rhythm?
Turns out it does — Value shines in January, Growth pops in June, Quality closes the year strong. Timing these beats standing still.
I unpack the patterns + heatmap here:
👉 open.substack.com/pub/tommijoh...
Turns out it does — Value shines in January, Growth pops in June, Quality closes the year strong. Timing these beats standing still.
I unpack the patterns + heatmap here:
👉 open.substack.com/pub/tommijoh...
The GenAI Divide is widening.
Winners? Firms using AI that adapts, integrates into workflows, & proves ROI.
Losers? Those chasing flashy demos without financial outcomes.
MIT’s State of AI in Business 2025 explains what investors should really watch: open.substack.com/pub/tommijoh...
Winners? Firms using AI that adapts, integrates into workflows, & proves ROI.
Losers? Those chasing flashy demos without financial outcomes.
MIT’s State of AI in Business 2025 explains what investors should really watch: open.substack.com/pub/tommijoh...
September 5, 2025 at 1:12 PM
The GenAI Divide is widening.
Winners? Firms using AI that adapts, integrates into workflows, & proves ROI.
Losers? Those chasing flashy demos without financial outcomes.
MIT’s State of AI in Business 2025 explains what investors should really watch: open.substack.com/pub/tommijoh...
Winners? Firms using AI that adapts, integrates into workflows, & proves ROI.
Losers? Those chasing flashy demos without financial outcomes.
MIT’s State of AI in Business 2025 explains what investors should really watch: open.substack.com/pub/tommijoh...
What if the Fed Chair could actually be fired by the White House?
Fed independence has kept inflation low & markets steady since 1913. Legal challenges now put that at risk.
More here 👉 tommijohnsen.substack.com/p/imagine-th...
Fed independence has kept inflation low & markets steady since 1913. Legal challenges now put that at risk.
More here 👉 tommijohnsen.substack.com/p/imagine-th...
Imagine the chair of the U.S. Federal Reserve getting a pink slip from the White House!
Fed independence is under fire. Does it matter? Oh yeah.
tommijohnsen.substack.com
August 27, 2025 at 10:21 PM
What if the Fed Chair could actually be fired by the White House?
Fed independence has kept inflation low & markets steady since 1913. Legal challenges now put that at risk.
More here 👉 tommijohnsen.substack.com/p/imagine-th...
Fed independence has kept inflation low & markets steady since 1913. Legal challenges now put that at risk.
More here 👉 tommijohnsen.substack.com/p/imagine-th...
Wall Street rallies. Main Street struggles. The Fed is the missing link.
Read how monetary policy fuels stocks:
👉 tommijohnsen.substack.com/p/from-free-...
Read how monetary policy fuels stocks:
👉 tommijohnsen.substack.com/p/from-free-...
From Free Markets to Fed Markets: How monetary easing (lowering interest rates) lifts stocks
In the past decade, central banks especially the U.S.
tommijohnsen.substack.com
August 19, 2025 at 12:09 PM
Wall Street rallies. Main Street struggles. The Fed is the missing link.
Read how monetary policy fuels stocks:
👉 tommijohnsen.substack.com/p/from-free-...
Read how monetary policy fuels stocks:
👉 tommijohnsen.substack.com/p/from-free-...