AUG · ISSUE 35 · August 29, 2026

CONCEPT

Recency bias

Your brain assumes whatever just happened will keep happening. In markets, that shortcut costs money.

WHAT IT IS

A shortcut

an automatic one

WHAT IT DOES

Extrapolates

the recent past

THE COST

Buy high

sell low

THE IDEA

Yesterday ≠ Tomorrow

the recent past is not a promise

Recency bias is the tendency to give more weight to what just happened than to all the history before it. If the market has been rising quietly for weeks, your mind assumes it will keep going, exactly when doubt serves you best.

AUG · ISSUE 35

THE EFFECT

Yesterday weighs more

2x

more weight on the recent than on the historical average

The brain overvalues what it just lived through. That is why a short streak feels like a permanent trend. An illustrative figure for the effect, not an exact measure.

Realizing you overweight the recent is the first step to not letting one month decide a strategy built for years.

OVERWEIGHT
To give a data point more importance than it deserves.
HISTORICAL AVERAGE
Long-run typical behavior, not this week's move.

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PRINCIPLE

Calm deceives

The greatest risk tends to arrive once everyone has decided there is no risk left.
Investing principle · Market wisdom

When volatility has been low for a while, recency bias convinces you it will stay low: precisely the moment to stay alert.

VOLATILITY
How much an asset moves: more movement, more uncertainty.
COMPLACENCY
Excess calm that often precedes surprises.

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HOW IT LOOKS

Where the bias catches you

You extrapolate hereYou extrapolate here
CalmRiseEuphoriaTurn

After a quiet climb, the bias makes you buy high, sure it will continue. The reversal arrives when you felt most certain. An illustration of the concept, not real data.

The point of peak optimism, where you extrapolate the calm, is usually the point of peak risk.

REVERSION
A price returning toward its average after moving far from it.
EXTREME
A zone of euphoria or panic where the bias hits hardest.

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SIGNS

Four traps of recency bias

  1. Buying at the top

    After weeks of gains you believe it cannot fall, and you buy exactly when risk is highest.

  2. Selling at the bottom

    After a drop you assume it will keep falling, and you sell exactly at the worst moment.

  3. Chasing past returns

    You pick the fund that rose most last year, ignoring that the past does not guarantee the future.

  4. Forgetting mean reversion

    You assume the expensive keeps rising and the cheap keeps falling, when both tend back toward their average.

Spotting these four traps is what separates a considered decision from an emotional reaction to the latest headline.

MEAN REVERSION
The tendency of prices to return to their average over time.
PAST RETURN
What an asset earned before: it does not predict what it will earn next.

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YOUR MIND

What you focus on when deciding

What just happened: 60%All prior history: 25%Cool analysis of today: 15%WEIGHTskewed
What just happened60%
All prior history25%
Cool analysis of today15%

Under recency bias, the recent eats most of your attention and crowds out calm analysis. An illustrative split of the concept.

If the recent takes 60% of your decision, you are not investing: you are reacting to the last move.

ANCHORING
Fixating on a reference figure that hijacks your judgment.
PROCESS
Deciding by rules and data, not by the emotion of the moment.

AUG · ISSUE 35

EXAMPLE

Same bias, different assets

Broad index~600 recent calmIllustrative: after rising, it is assumed to continue
Technology~500 hot streakIllustrative: chasing what rose most
Gold~4,600 pullbackIllustrative: after falling, it is assumed to continue
Long bond~90 high yieldsIllustrative: extrapolating the rate backdrop

The bias does not care about the asset: it works the same in stocks, gold or bonds. Rounded prices, for illustration only.

BROAD INDEX
A basket representing a whole market, not a single stock.
ILLUSTRATIVE
A teaching example: not a recommendation or a real price.

AUG · ISSUE 35

RONFY

Think in processes, not streaks

The antidote to recency bias is a plan written down before the emotion arrives.

Every weekend, one concept to invest with your head instead of the latest headline.

Follow us · @ronfy_official

Daily briefing · Mon-Fri 16:00 ET

PLAN
Rules set in advance so you do not improvise under pressure.
DISCIPLINE
Following the process even when emotion pushes the other way.

Sources: 🧠 Psychology · 📘 Core concept

Editorial content. Not financial advice.

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