The Disposition Effect: Selling Winners and Holding Losers
The disposition effect is the habit of realising gains more readily than losses. Across the Palash decision log, 61 of the 108 positions standing in gain were sold, or 56.5 per cent. Only 23 of the 132 standing in loss were sold, or 17.4 per cent. The ratio is 3.2 to 1. The raw share of sales that were winners, 72.6 per cent, is a much weaker number.
The whole thing rests on a division almost nobody makes when looking at their own record. How many of an investor's sales were winners is not, on its own, a fact about the investor. A winner that is not held cannot be sold, so the share is partly a fact about what happened to be held. Picture a fruit seller at the end of a long day being asked what share of what he sold was mangoes. The answer describes the cart before it describes the seller. Learning something about the seller means asking how much of the mango went and how much of the banana went, and comparing the two. The comparison of those two rates is the whole of the disposition effect. Each count of sales is divided by the positionsA position is one holding of one thing, tracked on its own, with its own cost and its own current value. of that kind that were there to be sold, and what survives the division is a fact about the deciding rather than about the cart. Sales divided by opportunity is the only form of the number that carries information about behaviour.
What is the disposition effect, once it is stated as a measurement?
Shefrin and Statman named the pattern in the Journal of Finance in 1985: a disposition to sell winners too early and to ride losers too long. Naming it was the easier half. The harder half was turning it into something a record could confirm or refuse. Count the sales, see how many were profitable, quote the share. The share of sales that were winners moves for reasons that have nothing to do with the person who made the sales.
Odean supplied the repair in Are Investors Reluctant to Realize Their Losses, in the Journal of Finance in 1998, and the repair is a denominator. Take every position standing in gain and ask what fraction of them was sold. Take every position standing in loss and ask the same. Two realisation ratesSales of one kind divided by the number of positions of that kind that were available to be sold. come out, one for gains and one for losses, and the disposition effect is the ratio between them. Stated as a measurement, the disposition effect is the rate at which gains are realised divided by the rate at which losses are realised, and a number above one is the effect. In the Palash decision log that ratio is 3.2 to 1. The ratio is not a claim that anybody sold too early. Each kind was equally available to sell, and 3.2 counts how differently the two were treated.
Why is the raw share of winning sales the wrong number?
Because it answers a question about the menu while sounding like a question about the diner. In an examination where nine of every ten questions are arithmetic, nine of every ten questions a candidate gets right will be arithmetic, whether arithmetic is that candidate's strength or that candidate's weakness. The share of the correct answers that were arithmetic is a fact about the paper. To learn anything about the candidate, somebody has to ask what share of the arithmetic was answered correctly and what share of the rest, and set the two side by side.
The raw shareThe proportion of the sales that were winners. The raw share rises and falls with what was available to sell, and describes the holding as much as the person. of winning sales in the Palash decision log is 61 of 84, which is 72.6 per cent, and it has exactly that defect. The 72.6 per cent was computed from a document that records sales and nothing else. Nowhere in a list of sales is there any record of what was sitting there unsold, and without that count there is no way to separate a person who reaches for gains from a person who simply held a great many gains. A share of sales is a fact about the holding and a fact about the deciding jammed together, and no amount of care with the sales list will pull them apart. The repair is not a better sales list. The repair is a second document.
What is a realisation rate?
What are the two realisation rates in the Palash decision log?
Now bring in the second document and the arithmetic falls out in one line each. Across the eight quarters the Palash decision log carries 240 open positions. Of those, 108 stood in gain and 132 stood in loss, and 108 plus 132 returns the 240. Of the 84 sales, 61 closed a position that stood in gain and 23 closed one that stood in loss, and 61 plus 23 returns the 84. Every position is therefore in exactly one of four states, and the four states account for all 240.
| What kind of position | Available to sell | Sold | Never sold | Realisation rate |
|---|---|---|---|---|
| Standing in gain | 108 | 61 | 47 | 56.5 per cent |
| Standing in loss | 132 | 23 | 109 | 17.4 per cent |
| All positions | 240 | 84 | 156 | ratio 3.2 to 1 |
The two rate cells carry the whole argument. A gain standing in the log had a 56.5 per cent chance of being closed over the eight quarters; a loss had a 17.4 per cent chance. The first divided by the second is 3.2, and that ratio is the disposition effect stated as a measurement. Gains in the Palash decision log were realised at 3.2 times the rate at which losses were realised, and that sentence survives every change in what the 60 investors happened to be holding. Notice what the table also shows. Only 47 gains were carried on unsold against 109 losses, so the holding fills up with losses, not because anything was chosen but because the gains kept leaving and the losses kept staying.
61 of the 84 sales in the Palash decision log were winners. What does 72.6 per cent establish about behaviour?
What does the ratio survive that the raw share does not?
Here is the test that settles it, and it is worth doing slowly. Freeze the behaviour. Say that whoever is deciding will always close 56.5 per cent of the gains standing in front of them and 17.4 per cent of the losses, no matter what is in front of them. Now change nothing about the person and change only the opportunityHow many positions of each kind were there to be sold. The count is the denominator, and it is set by what happened to be held rather than by any decision. they face.
With 50 of the 240 standing in gain and 190 standing in loss, that unchanged behaviour produces 28.2 gain sales against 33.1 loss sales, and the raw share of winning sales comes out at 46.0 per cent. With 200 in gain and 40 in loss, the same unchanged behaviour produces 113.0 against 7.0, and the raw share comes out at 94.2 per cent. The same two rates produce a raw winners share anywhere from 46.0 per cent to 94.2 per cent, and the person has not changed by so much as a decision. The two rates divided instead give 3.2 to 1 at the first setting, 3.2 to 1 at the second and 3.2 to 1 at the log's own split. A measurement is the number that stops moving when the things it is not about are moved.
Before the control below is moved: can one unchanged pair of realisation rates produce a raw winners share of 46 per cent and also one of 94 per cent?
Move the mix and watch one number swing while the other refuses
One variable moves: how many of the 240 open positions stand in gain, from 20 to 220, with the rest standing in loss. Two things are held fixed by stipulation at every setting: gains are realised at 61 of 108, which is 56.5 per cent, and losses at 23 of 132, which is 17.4 per cent. At the log's own split of 108 and 132 the raw share of winning sales is 72.6 per cent. At 50 and 190 it is 46.0 per cent, and at 200 and 40 it is 94.2 per cent. The ratio of the two rates is 3.2 to 1 wherever the slider is set.
With 108 of the 240 positions standing in gain and 132 standing in loss, the two fixed rates close 61 gains and 23 losses, so 72.6 per cent of the sales are winners and the ratio is 3.2 to 1.
The raw share has just travelled most of the scale. What stayed fixed while it moved?
What is Realisation Utility, and what does it add to the account?
Everything so far has been counting. One idea is not enough to explain why the pattern happens. A second idea is needed. Ask why a loser gets kept and the answer is reasonably well settled: the position is being scored against what it cost, and closing it turns a paper lossA loss on a holding that is still held. The money is just as gone as in a realised loss, but it has not been written into the record yet. into a settled one. The reference point handles that much on its own. Now ask the other question. The winner is still doing exactly what it was bought to do, so why is it sold, and often early? A position above its cost is comfortable to hold, so the reference point has nothing much to say about the selling.
Realisation utilitySatisfaction taken in the act of closing a position at a gain, counted separately from the money the closing produces. is the second idea, set out by Barberis and Xiong in the Journal of Financial Economics in 2012. The idea is that a person takes satisfaction from the act of booking a gain itself, separately from what the money then does. Think of a household that has spent three weekends repainting a room. The pleasure is concentrated in putting the brush down and standing back, not in the paint. Realisation utility puts a second term into the account: one for the position and one for the act of closing it, and only the second explains why a gain gets taken early. Both terms are needed, and the log cannot show how much of the 56.5 per cent belongs to which.
What does realisation utility add that the reference point does not supply on its own?
Why does the reference point alone leave half the pattern unexplained?
Because the pattern has two halves and the reference point is built to explain one of them. A holding standing below its cost sits in the region where taking the chance is preferred to settling, and that is a complete account of a loser being kept. Run the same reasoning upward and it says a holding standing above its cost will be closed rather than risked. The direction is right and the timing is missing. The reference point does not explain why the closing happens now, at a modest gain, in a position nothing has gone wrong with. A satisfaction attached to the act of closing is collected the moment the act happens, and waiting postpones it, so realisation utility supplies the missing timing. They answer different questions, and a reader who collapses them into one loses the ability to say which part of a record is being explained by which.
How does the pattern differ from booking a loss on purpose?
Disposition Effect vs Tax-Loss Harvesting
The disposition effect and tax-loss harvesting look like opposites, and are usually confused in the other direction. Tax-loss harvestingClosing a position that stands at a loss on purpose, so the loss is recorded and can be set against something for tax. The reason is the tax treatment, not the position. is the deliberate closing of a position standing at a loss so that the loss is recorded. Whatever a reader thinks of it, it is a decision taken for a stated reason, and it produces a record that is the mirror image of the disposition effect: losses realised readily, gains left standing. Measured against opportunity in the same way, its ratio would sit below one rather than above.
The difference matters for reading any log, including a reader's own. The disposition effect and tax-loss harvesting produce opposite records from opposite intentions, and neither of them is visible in a return figure. A person doing one and a person doing the other can finish a period with the same number at the bottom of the statement. Only the two realisation rates, counted separately against what was available, tell them apart. And a ratio below one is not proof of careful tax practice either. The measurement identifies the pattern. The measurement never identifies the reason.
Where the tax treatment of a realised loss is settled
How a realised loss may be treated, and what conditions attach, is a matter of the tax law in force and of the disclosure and conduct requirements that apply to a registered intermediary. The Securities and Exchange Board of India at sebi.gov.in is the place to confirm the conduct side, and the tax treatment itself must be confirmed against the law as it stands. Whether realising a loss is worth doing at all turns on a tax position that differs from one person to the next.
Somebody deliberately closes a position standing at a loss, wanting the loss recorded. Which pattern is that?
What did the pattern cost in the case, and what does that figure not prove?
On 12 October Meera Sundaram sold Suvarna Chemicals Limited whole at Rs 4,60,000/-, booking Rs 60,000/- on a cost of Rs 4,00,000/-. The same evening she kept Kesari Logistics Limited, then standing at Rs 1,95,000/- against the Rs 3,00,000/- it had cost, and said she would sell it when it got back to Rs 3,00,000/-. The winner went and the loser stayed.
Reading the pair as a verdict on the sale, and what that reading costs
By the following 31 March, Suvarna Chemicals Limited had risen a further 8.0 per cent, so the Rs 4,60,000/- realised would have been Rs 4,96,800/-, and Rs 36,800/- was forgone. Kesari Logistics Limited had fallen a further 20.0 per cent, from Rs 1,95,000/- to Rs 1,56,000/-, losing another Rs 39,000/-. The pair cost Rs 75,800/-. And in the same breath: one pair of decisions establishes nothing whatever about whether a rule works.
The error is treating Rs 75,800/- as proof that selling the winner was wrong and keeping the loser was wrong. The figure is proof of neither. Reverse the two movements, no less possible on 12 October, and the identical pair of decisions looks shrewd. The error costs the ability to tell a finding from an anecdote. A reader who accepts Rs 75,800/- as evidence has accepted a sample of one, and will accept the next one just as readily, including one pointing the other way.
The Palash decision log does support the rate difference: across 240 open positions, gains were realised at 56.5 per cent and losses at 17.4 per cent. A rate difference is a claim about a pattern across many decisions, and it is the only kind of claim 240 positions can carry. Whether any single sale was sound is not measurable from a log at all.
The 12 October pair cost Rs 75,800/- by the following 31 March. What does that figure establish?
When is selling a winner first exactly the right move?
Often. A rate difference of 3.2 to 1 makes no particular sale wrong. A position that has grown until it takes up far more of a holding than it was ever meant to is being sold because of the position. A holding sold because the reason for buying it has gone is being sold because of the position. Money needed in March is a reason about the money. A sale is the disposition effect when the gain itself is the reason, and not when a winner merely happens to be the thing sold. The test is a question asked before the sale rather than after it, and the honest answer is usually available in about ten seconds: if the position were standing exactly where it was bought, would the sale still be happening today? If yes, the reason is about the position. If the only thing that changed is that it is up, the gain is the reason.
When is selling a winner first the right move?
How does somebody reading a decision log actually use two rates?
What an adviser, an analyst or a person deciding alone does with this on a Tuesday
Devika Rao, the adviser at Palash Advisory Services Private Limited, needs no study to run this. She needs two counts she already has. At the end of a quarter she lists every position that stood in gain and counts how many were closed, then does the same for every position that stood in loss. Two divisions, then one more, and the ratio is written down. The count takes an afternoon and needs no record that does not already exist.
The ratio hands her a question rather than an answer. A ratio near one says gains and losses were closed at similar rates. A ratio well above one says something is selecting for gains, and the next step is to read the written reasons, not to conclude anything. A ratio below one is the opposite pattern, and it might be deliberate tax practice or might not.
A person deciding alone, with no adviser and no committee, runs the identical count on the identical two documents. The measurement is cheap, it needs no new paperwork, and it answers something a turnoverHow much was bought and sold over a period, as a share of what is held. Turnover counts volume and says nothing about which positions moved. figure cannot even ask: not how much went, but which ones. What it never hands anybody is a verdict on a particular sale.
Sources
| Source | Document | Site |
|---|---|---|
| Shefrin and Statman | the paper that named the pattern of realising gains too readily and losses too slowly, Journal of Finance, 1985 | ssrn.com |
| Odean | Are Investors Reluctant to Realize Their Losses, Journal of Finance, 1998, which measured the pattern against opportunity rather than against sales | ssrn.com |
| Barberis and Xiong | the paper setting out realisation utility as a term attaching to the act of closing a position, Journal of Financial Economics, 2012 | ssrn.com |
| Kahneman and Tversky | the 1979 paper setting out prospect theory, Econometrica, named here only to say where the mechanism is treated | nber.org |
| Securities and Exchange Board of India | conduct, suitability and disclosure requirements applying to registered intermediaries, and the place to confirm any tax treatment of a realised loss | sebi.gov.in |
| Association of Mutual Funds in India | investor-facing practice guidance for distributors and registered advisers | amfiindia.com |
Meera Sundaram, Devika Rao, Palash Advisory Services Private Limited, the Palash decision log, the Palash 100 index, the Vindhya index scheme, the Nilgiri mid-cap scheme, Suvarna Chemicals Limited and Kesari Logistics Limited are invented.
Educational material. Not advice on any investment, tax, budget or market position.
