The disposition effect describes investors' tendency to realize gains while holding losing positions. Alex Imas links the pattern to the emotional reward of discussing profitable sales and the discomfort of admitting losses, with some investors buying more merely to break even.

Investors disproportionately realize gains.
Losing positions are often retained in hope of recovery.
Social and emotional rewards influence sale decisions.
Doubling down can be motivated by a desire to reach the purchase price.

“So it's this tendency to realize your gains and hold on to your losses.”
Alex Imas · 34:04

“cutting your flowers and watering your weeds.”
Barry Ritholtz · 34:09

#disposition effect#loss aversion#investing

Myth Buster42:08

The Foundational Behavioral Anomalies Still Replicate

Thaler and Imas reran classic experiments on a new online population and reviewed decades of external-validity evidence. They report that foundational effects such as loss aversion, the endowment effect, and the conjunction fallacy continue to appear beyond their original college-lab settings.

Classic experiments were directly replicated on Prolific.
Replication materials were published for others to rerun.
The effects extend beyond low-stakes student samples.
The equity premium puzzle remained broadly stable over four additional decades.

“Basically, everything works. Everything works,”
Alex Imas · 43:20

“people aren't learning the psychology is the same.”
Alex Imas · 44:22

#replication#loss aversion#research methods

Hot Take· 1

Hot Take52:40

Biases That Aided Survival Can Misfire in Modern Finance

Human psychology evolved for subsistence, social cooperation, and immediate physical risks rather than portfolio management or decades-long retirement planning. Loss aversion may once have protected survival while creating unhelpful reactions in modern financial settings.

Evolution does not guarantee that present behavior is optimal.
Loss aversion can be adaptive near subsistence.
Portfolio management has no long evolutionary history.
Long retirements create historically new planning demands.

“we evolved on the savannah.”
Richard Thaler · 52:54

“there's no evolutionary history of how to manage a portfolio,”
Richard Thaler · 53:59

#evolution#loss aversion#retirement

Explainer· 5

Explainer01:42

Behavioral Economics Began With Predictable Model Errors

Richard Thaler explains that behavioral economics is not merely the observation that people make mistakes. Its useful contribution is identifying systematic, directional deviations from economic models, which can generate testable predictions.

Traditional models described abstract agents rather than realistic people.
Kahneman and Tversky showed that deviations were predictable.
Directional errors are more actionable than simply declaring a model wrong.

“What they showed was that behavior is predictably different from the model that economists use.”
Richard Thaler · 02:51

“It's fine to say stock prices are wrong. That's fine, but useless.”
Richard Thaler · 03:26

#behavioral economics#economic models#prediction

Explainer07:14

Why News Coverage Distorts Our Perception of Risk

The availability heuristic makes events feel more likely when examples come readily to mind. Heavy reporting on homicide, terrorism, and shark attacks can therefore crowd out more common but quieter risks such as suicide and chronic disease.

Ease of recall is often mistaken for probability.
Media attention is not proportional to real-world prevalence.
Quiet, common harms can be systematically underestimated.

“if it's easier to think of examples of something, it's more likely.”
Richard Thaler · 07:27

“notice this is a predictable mistake.”
Richard Thaler · 08:00

#availability bias#risk#media

Explainer16:11

Where Money Sits Changes How People Spend It

Economic models often combine every asset into one measure of wealth, but people maintain separate mental accounts. A rise in home value, a cash payment for acquired stock, and a lottery win can produce very different spending responses even when each increases net worth.

People do not treat all dollars as perfectly fungible.
Housing wealth produces little immediate spending in the example discussed.
Liquid windfalls are more likely to be spent.
Labels and account boundaries influence consumption.

“So where the money sits has a big effect on how much of it you spend.”
Richard Thaler · 17:34

“All dollars are fungible.”
Barry Ritholtz · 18:45

#mental accounting#wealth effect#spending

Explainer45:49

Basic Priming Is Robust; Elaborate Behavioral Priming Often Is Not

Alex Imas distinguishes basic cognitive priming from elaborate studies that infer large behavioral consequences from indirect cues. Richard Thaler adds that selecting large, established effects made the anomalies he covered more likely to survive replication.

Basic memory priming remains robust.
Indirect priming studies can give researchers excessive analytical freedom.
Small, clever effects are more vulnerable to replication failure.
Large effect sizes provide a stronger foundation for reusable findings.

“Basic priming is very robust.”
Alex Imas · 45:49

“I picked big effect sizes”
Richard Thaler · 47:39

#priming#replication#psychology

Explainer49:49

The Ultimatum Game Shows That People Pay to Reject Unfairness

In the ultimatum game, a responder can reject an unfair division and leave both parties with nothing. Contrary to a money-only model, low offers are often rejected because people care about fair treatment as well as financial payoff.

A purely monetary model predicts acceptance of any positive amount.
Offers below roughly twenty percent are commonly rejected.
Most proposers offer approximately half.
The result challenges narrow assumptions about preferences, not game theory itself.

“If he says no, you both get nothing.”
Richard Thaler · 50:19

“It was challenging the idea that the agents only care about money and don't care about being treated fairly.”
Richard Thaler · 51:43

#fairness#ultimatum game#social preferences

Story· 1

Story1:01:42

NFL Teams Pay Huge Premiums for a Tiny Forecasting Edge

Thaler's NFL draft research found that expensive early selections can deliver less value than packages of lower picks. Teams have only a slight ability to identify which adjacent player at the same position will perform better, yet confidence in top prospects remains high.

Top picks carry high salary and opportunity costs.
Trading down can produce more total value.
Earlier players beat the next-ranked player only slightly more often than chance.
Quarterback importance does not eliminate selection uncertainty.

“if you trade the first pick for lower picks, you get more.”
Richard Thaler · 1:02:39

“there's only a fifty three percent chance that he's better than the next one.”
Richard Thaler · 1:06:05

#nfl draft#overconfidence#forecasting

Takeaway· 4

Takeaway35:49

Familiarity Can Double Your Exposure to the Same Risk

Home bias concentrates portfolios in an investor's country, region, industry, or employer. Employee stock is especially dangerous because a company failure can simultaneously destroy employment income and retirement savings.

Investors overweight familiar domestic companies.
Regional familiarity can create sector concentration.
Employer stock compounds human-capital and portfolio risk.
Home bias appears even in small countries with access to global markets.

“You already have a bunch of ron stock in your four one k. You shouldn't be taking your discretionary spending and buying more and ron…”
Alex Imas · 37:56

“They were putting most of their money in Swedish stocks.”
Richard Thaler · 38:38

#home bias#diversification#portfolio risk

Takeaway1:12:49

If Experts Cannot Beat the Betting Market, Keep Your Stakes Small

Thaler cautions that sports-betting apps and gamified investment products exploit attention and make odds difficult to assess. Because prohibition is unlikely to work, he favors better disclosure and limiting speculative activity to money the user can afford to lose.

Gamified platforms can turn behavioral knowledge against users.
Even sophisticated gamblers may struggle to make money.
Short-dated options can resemble gambling more than investing.
Speculation should never endanger essential savings.

“if Nate can't make money doing this, chances are you can't.”
Richard Thaler · 1:14:48

“if you really think you doing this, do it on a small scale.”
Richard Thaler · 1:14:58

#gamification#sports betting#options#risk

Takeaway1:17:12

Modern Behavioral Finance Requires Coding and Messy-Data Experience

Alex Imas advises aspiring behavioral economists to combine economics and finance knowledge with coding, machine learning, and AI skills. Thaler adds that practical experience cleaning noisy real-world data cannot be learned solely from textbooks.

Learn to code rather than relying only on prompting tools.
Take computer-science courses alongside economics and finance.
Field data sets require sophisticated analysis.
Cleaning noisy data is a practical skill learned through experience.

“I think you still got to learn to code.”
Alex Imas · 1:17:33

“learning how to clean up a data set. You got to learn that through experience.”
Richard Thaler · 1:18:59

#career advice#coding#data science

Takeaway1:23:10

Study the Population That Matters, Not Just the Data You Can Find

Imas argues that behavioral finance advances when researchers obtain data from consequential populations such as institutional investors. Repeatedly analyzing one convenient historical retail data set limits what the field can credibly say about modern finance.

Available data can trap research under the proverbial streetlight.
Retail-trader findings do not automatically generalize to institutions.
High-impact research often requires difficult data acquisition.
The target population should determine the data, not the reverse.

“you can't have a field evolve looking at three years of retail traders with ten thousand dollars portfolios.”
Alex Imas · 1:24:37

“It's the power of getting data sets and running analyzes on on populations that are important for the economy and for finance.”
Alex Imas · 1:24:50

#research design#institutional investors#data

Frameworks in this episode

Default-Based Choice Architecture

Predict the Mistake, Not the Outcome

Symmetric Buy-Sell Decision Process

Winner's Curse Bid Adjustment

Insights & moments

⚡Myth Buster· 2

Investors Sell Winners and Keep Losers for Emotional Reasons