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Disposition Effect in Trading: Track PGR and PLR Before Your Next Exit

October 13, 2026
Disposition Effect in Trading: Track PGR and PLR Before Your Next Exit

The disposition effect is the tendency to sell winning positions too early and hold losing positions too long, and it quietly erodes both returns and tax efficiency. Classic research found retail investors realized far more gains than losses, even though sold winners went on to outperform the losers left in the portfolio. The fix starts with measuring the bias in your own trade history, understanding why it happens, and applying a few concrete process changes.

TL;DR:

  • Audit a year of trades by comparing PGR, realized gains over all gain opportunities, with PLR, realized losses over all loss opportunities; repeat quarterly.
  • An experiment involving 193 professionals found that holding losers can be rational when prices revert toward the mean; prompts improved outcomes when they do not.
  • In taxable accounts, offset gains with losses and avoid buying substantially identical securities within 31 days after a loss sale; select specific lots.
  • Log each entry thesis and set exit rules beforehand; scheduled reviews can then test decisions against the plan, not current profits or losses.
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Table of Contents

What the disposition effect is and how researchers measure it

The disposition effect describes a trader's pull toward locking in profits quickly while letting losing trades ride, a pattern first framed by Shefrin and Statman using prospect theory to explain why gains and losses get treated so differently. Researchers typically quantify it with two ratios drawn from trade history:

  • PGR (proportion of gains realized): realized gains divided by realized gains plus paper gains still open.
  • PLR (proportion of losses realized): realized losses divided by realized losses plus paper losses still open.

Say you closed 10 winning positions out of 15 total winning opportunities, and closed only 4 losing positions out of 20 total losing opportunities. Your PGR would be 0.67 and your PLR would be 0.20. A PGR well above your PLR is the numerical signature of the disposition effect.

Empirical evidence: classic results and recent experiments

The foundational study of this bias analyzed 10,000 discount brokerage accounts from 1987 to 1993 and found investors realized gains at a notably higher rate than losses, with sold winners outperforming the retained losers by roughly 3.4 percentage points over the following year. Practitioner summaries, including a CFA Institute digest connecting disposition patterns to price momentum, have kept this finding central to behavioral finance ever since.

More recent work complicates the picture. A within-subject experiment with 193 professional traders found the disposition effect can actually be rational when a security is mean-reverting, but harmful when it is not, and a simple informational intervention reduced the bias and improved returns specifically in the non-mean-reverting cases.

  • Odean's original finding established PGR consistently exceeding PLR across a large retail sample.
  • The professional-trader experiment shows context, specifically whether an asset tends to revert to a mean, changes whether the same selling pattern helps or hurts.
  • Informational nudges that redirect attention to objective criteria, rather than unrealized profit and loss, measurably shifted trader behavior in the experiment.

Why the disposition effect happens: the psychology behind it

Four mechanisms drive this pattern, and recognizing them in the moment is the first step to interrupting them.

  • Prospect theory: the value function is concave for gains and convex for losses, so traders become risk-averse once ahead and risk-seeking once behind, pushing toward an early exit on winners and a reluctant hold on losers.
  • Loss aversion and regret avoidance: closing a winner confirms you were right, while closing a loser makes the loss final and undeniable, so the mind delays that confirmation.
  • Mental accounting: each position gets treated as its own separate ledger anchored to the original purchase price, rather than as part of one portfolio.
  • Context dependence: a theoretical analysis from NBER shows prospect-theory preferences do not always predict disposition-style behavior, since the prediction depends on expected returns and time horizon, which is why checking the asset's behavior matters before assuming the pattern is a mistake.

We cover the related mechanics of loss aversion in trading in more depth, since it is the single strongest driver of the hold-the-loser half of this bias.

Measurable costs: performance drag and tax inefficiency

The follow-through gap is the clearest cost: winners sold too early kept outperforming the losers that stayed in the account, by about 3.4 percentage points over the next year in the original brokerage-account study. In a taxable account, the damage compounds. Selling winners accelerates tax liability, while holding losers forfeits a deduction you are entitled to take now. The wash-sale rule adds a timing trap of its own, disallowing a loss deduction if you buy a substantially identical security within 31 days of the sale.

  • Realizing gains early triggers tax now instead of later, when a lower rate or offsetting loss might apply.
  • Holding losers past their logical exit point means the deduction sits unused for months or years.
  • Practitioner estimates put the disposition-driven tax drag at a small but noticeable fraction of annual return in taxable accounts, according to tax-focused practitioner summaries of this behavior pattern.

How to check your own PGR and PLR

A PGR/PLR audit takes about 20 minutes with a year of trade history exported from your broker.

  1. Pull every closed trade for the period, separating each into a realized gain or a realized loss.
  2. Pull every open position still showing an unrealized gain or an unrealized loss as of the same date.
  3. Calculate PGR: realized gains divided by (realized gains plus unrealized gains).
  4. Calculate PLR: realized losses divided by (realized losses plus unrealized losses).
  5. Compare the two. A PGR noticeably higher than your PLR, the pattern Odean's data showed across thousands of accounts, signals the disposition effect is active in your decisions.
  6. Repeat the audit quarterly and track whether the gap narrows.

Taxable accounts deserve lot-level attention, since specific-lot selection lets you choose which shares to sell for tax purposes, while retirement accounts remove the tax variable entirely and isolate the pure behavioral pattern.

Pro Tip: Log the thesis that justified each entry, not the current profit or loss, so your exit decision gets compared against your original reasoning instead of today's account balance.

Practical tactics to reduce the disposition effect

Measurement only matters if it leads to a changed process. These tactics map directly to the evidence above.

  • Journal the entry thesis and review on a schedule, not when a position moves against you, so the decision to exit gets compared to your original reasoning rather than your current mood. Our trading journal guide walks through what to log and why it holds up over time.
  • Use paired selling and gain-loss offsetting when closing positions in a taxable account, matching a realized gain against a realized loss in the same tax year to blunt the drag described above.
  • Apply simple informational nudges, the kind of reminder that redirects attention to your plan instead of your open profit, which the professional-trader experiment found measurably improved outcomes.
  • Pre-commit to stop and scale rules before entry, so the exit decision is made once, in a calm moment, rather than repeatedly under pressure.
  • Check whether the asset is mean-reverting before assuming your instinct to hold a loser is wrong. In mean-reverting markets, the same pattern the research criticizes in equities can be the economically sound choice.

Pro Tip: Schedule your portfolio review for a fixed day each week rather than reacting to price moves, since a calendar-driven review removes the emotional trigger that normally prompts an early exit on winners.

How decision intelligence turns these tactics into a routine

A disposition-effect fix only sticks when it becomes a repeatable habit rather than a one-time insight. Decision intelligence tools built for self-directed traders can operationalize the audit and the nudges described above: scoring each setup, flagging when a pattern resembles past disposition-driven exits, and prompting a journal entry at the moment of decision rather than after the fact.

  • Decision scoring that evaluates the setup itself, separate from the unrealized profit or loss sitting in the account.
  • A built-in journaling and trade-review workflow that captures the entry thesis automatically rather than relying on memory.
  • An assistant that surfaces your own historical PGR/PLR pattern instead of a generic market signal.

Readers who prefer a manual version can replicate most of this with a spreadsheet, a calendar reminder, and the quarterly audit outlined above. We detail the mechanics further in our overview of behavioral trading and retail P&L.

Impact on different trading styles

The disposition effect shows up differently depending on how often you trade and how long you intend to hold.

Day traders feel the cost fastest, since dozens of small decisions compound the pattern within a single session: a winning scalp gets closed in seconds while a losing position gets nursed through multiple stop adjustments, turning a planned one percent loss into a much larger one. The short time frame also means there is little room for the mean-reverting exception described earlier, since most day-trading setups are momentum-based rather than mean-reverting, making an early exit on strength and a slow exit on weakness almost always the wrong order of operations.

Swing traders holding positions for days to weeks sit in the middle ground. Here, the mean-reversion question actually matters: a swing trade in a range-bound security might justify patience with an open loss, while the same patience in a trending breakdown compounds the damage.

Long-term investors face a subtler version of the bias, since the temptation is not to day-trade out of a winner but to trim a strong position "to lock in gains" while letting a structurally impaired holding sit untouched for years under the label of a long-term investment. The tax consequences are larger here too, since long-term capital gains rates reward patience with winners precisely when the disposition effect pushes toward selling them.

Across all three styles, the diagnostic stays the same: calculate PGR and PLR for the relevant holding period and compare them, since the ratio reveals the pattern regardless of how fast you trade.

Why individualized bias scoring beats generic advice

Generic behavioral finance content tells you loss aversion exists and recommends you "stick to your plan." That advice is true and almost useless on its own, because it does not tell you which of your specific setups, symbols, or market conditions trigger the pattern most strongly.

Individualized scoring addresses that gap by evaluating your own trade history rather than a textbook example. A trader whose disposition effect concentrates in options positions needs a different intervention than one whose bias shows up only after a losing streak, and only a bias score built from personal trade data can make that distinction. This is also where the mean-reversion caveat from the professional-trader experiment becomes practical rather than theoretical: a scoring system that accounts for the asset class you actually trade can tell you when your instinct to hold is statistically defensible and when it is the disposition effect in disguise.

The six-factor analytical approach behind our decision intelligence platform was built around this distinction, scoring each setup on the behavioral and psychological factors behind the decision rather than issuing a signal or prediction. The goal is not to tell you what to trade next, but to show you the pattern in your own history so you can correct it yourself. That kind of personalized feedback loop is the difference between knowing the disposition effect exists and actually reducing your own PROPER gap over time.

Common behavioral traps tied to the disposition effect

A few recurring traps show up alongside the core bias, and each has a specific countermeasure.

Anchoring to the purchase price is the most common: a stock bought at $50 that falls to $40 gets judged against $50 forever, even after new information has made that reference point irrelevant. The fix is to re-underwrite the position periodically as if you were buying it fresh today, ignoring your cost basis entirely.

Averaging down on a loser to "improve the average" often masks disposition behavior as a risk-management strategy, when it is really a way to delay admitting the original thesis failed. A pre-committed sizing rule, decided before the trade, removes the temptation to add to a loser in the moment.

The December tax-loss flip is a seasonal version of the same trap: practitioner summaries of the original research show investors reverse their usual pattern and finally sell losers in December, purely for tax purposes, which confirms the behavior is driven by tax timing rather than by genuine reassessment of the position. Scheduling loss reviews monthly, rather than waiting for year-end, spreads that decision out and removes the rushed, tax-driven exit.

Finally, treating each position as an isolated bet rather than part of one portfolio, the mental accounting trap, makes it easy to justify holding one specific loser "until it comes back." Reviewing the portfolio as a single unit, with one combined profit-and-loss number, breaks that isolation.

Common behavioral traps tied to the disposition effect — overview diagram

Case examples of behavioral change improving outcomes

Consider a trader running a straightforward audit: pulling a year of closed and open positions, calculating PGR and PLR, and finding a PGR of 0.70 against a PLR of 0.25, a textbook disposition signature. After instituting a weekly scheduled review and a rule requiring a written thesis re-check before closing any winner early, the same trader recalculates PGR and PLR the following quarter and finds the gap has narrowed, with PLR rising as losers get cut closer to the original stop level instead of being held indefinitely.

Initial PGR and PLR show a gap

A second illustrative case involves a swing trader who discovers, after checking the mean-reversion question, that most of the stocks triggering the bias were actually trending breakdowns rather than range-bound names, meaning the instinct to hold had been genuinely costly rather than statistically defensible. Narrowing the "hold through weakness" rule to only range-bound setups, identified through a simple moving-average channel check, removed the disposition effect's influence in every other context while preserving it where it had actually been rational.

These examples illustrate the mechanism, not a guaranteed result: the before-and-after PGR/PLR comparison is a measurement tool, not a promise, and the size of improvement depends on how consistently the review process gets followed.

What matters most if you only fix one thing

The conventional advice on this topic stops at "be aware of your biases," which is close to useless on its own. Awareness without measurement is just a feeling, and feelings are exactly what got you into the disposition effect in the first place. If we had to prioritize one change, it would be the PGR/PLR audit itself, run quarterly, because it turns a vague sense of "I think I sell winners too fast" into a number you can track and argue with.

The tax angle gets underweighted in most popular writing on this topic, treated as an afterthought when it is often the larger dollar cost of the two. A trader who fixes the behavioral pattern but ignores wash-sale timing and lot selection has only solved half the problem.

The mean-reversion caveat is the most overlooked nuance. Not every instance of holding a loser is a mistake, and treating the disposition effect as an absolute rule to fight in every context will cost you money in markets where patience happens to be the rational choice. Check the asset before you fight the instinct.

— Anantha

Try a platform built to flag this pattern in your own trades

A PGR/PLR audit tells you the disposition effect is present, but catching it setup by setup, in real time, is a different job entirely. We built our decision intelligence platform to score each trade setup on the behavioral factors behind it, not on a market forecast, so the pattern shows up before you close the position rather than in a quarterly spreadsheet review.

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FAQ

What does disposition mean in economics?

In behavioral economics, disposition refers to the tendency to sell assets that have gained value while holding onto assets that have lost value, a pattern first framed using prospect theory. The term comes from "the disposition to sell winners too early and ride losers too long," the original phrasing used by Shefrin and Statman.

What is Warren Buffett's 70/30 rule?

This specific rule is not documented in the primary behavioral finance research or regulatory sources we rely on for this article, so we cannot confirm a verified definition. Readers researching portfolio allocation guidance should look to a named, sourced framework rather than an unverified rule attributed informally.

What are the three types of investors?

Investor classifications vary by framework, but a common practical split used in trading psychology is risk-averse, risk-neutral, and risk-seeking, based on how each responds to uncertain outcomes. Behavioral finance adds a fourth lens on top of this: how prone an investor is to biases like the disposition effect, loss aversion, and mental accounting, regardless of their baseline risk preference.

What are the three types of risk preferences?

The three standard risk preferences are risk-averse, risk-neutral, and risk-seeking, describing how a person weighs a certain outcome against an uncertain one of equal expected value. A risk-averse trader prefers the certain outcome, a risk-seeking trader prefers the gamble, and a risk-neutral trader is indifferent between the two when expected values match.

How do I calculate my own disposition effect?

Calculate your proportion of gains realized (PGR) and proportion of losses realized (PLR) from a year of trade history: PGR is realized gains divided by realized gains plus paper gains, and PLR is realized losses divided by realized losses plus paper losses. A PGR meaningfully higher than your PLR indicates the disposition effect is present in your trading.

Sources

Key primary studies and practitioner summaries