Tag Archives: incentives

Equilibrium response to reduced material use for plastic bags

Probably to save material on the manufacture of the free plastic shopping bags in the US, these bags are small and thin compared to the ones in Estonia (which used to be free, but are now priced at significantly above production cost due to EU regulations on disposable plastic products). The equilibrium response of cashiers and customers to thin flimsy bags is to double-bag groceries, a practice unheard of in Estonia. After all, if one bag is sturdy enough, almost nobody will use two inside each other. I have successfully carried 10 kg in an Estonian plastic bag.

The equilibrium response to small bags is to distribute the groceries among many bags, especially the heavy or bulky items, for example to put each milk canister or large salad sack into a separate bag. Both double-bagging and the one-item-per-bag distribution lead to more bags being used in response to manufacturing each bag out of less material. It is an empirical question whether thinner, smaller bags result in less or more plastic waste overall. To incentivise reducing the one-time use of plastic bags and to encourage reuse, customers should have to pay for these, like in the EU.

One form of plastic bag reuse is as garbage bags (although it is only a one-time reuse, it is better than nothing). However, the flimsy free bags in the US come in bulk packs with the bottoms of the bags stuck together, so separating one from the stack often results in holes in its bottom an inch wide or more. The holes discourage many forms of reuse, including as trash bags, because small items (dust, crumbs, scraps) fall out. Partly the holes are due to the flimsiness of the material, partly to the way the bags are glued together to make a bulk pack.

Fund management fee paid explicitly to nudge consumers to choose better funds

Mutual funds with lower management fees have higher future before-fee returns (Gil-Bazo and Ruiz-Verdu 2009). Nonetheless, the high-fee funds have not gone out of business, so there must exist a sizable number of silly customers who accept low returns without switching to competitors. When asked explicitly, all fund investors prefer more money to less. Their hourly wage is not large enough to explain their non-switching with the time and hassle costs of comparing fund returns and choosing a new one. Similarly, many Estonians keep their retirement savings in badly performing high-fee pension funds despite the availability of dominating options (Tuleva and LHV index tracking funds). This is costing the customers over one percent of their retirement wealth per year.

By contrast, people with chronic or expensive diseases in the US often pick the health insurance plan that maximises their wealth (coverage minus premiums). This dynamic optimisation involves switching to a different plan when their illness changes. People without costly medical conditions tend not to switch their insurance even when cheaper plans with higher coverage are available.

Both the pension and the insurance plan decisions are complex, but matter greatly for wealth. Why do people pay attention to the financial consequences of their insurance choice when sick, but ignore better options among pension funds (and when healthy, also among insurance plans)? One possibility is that insurance is more salient to the sick, and the greater attention leads to better decisions. Specifically, the premiums and out of pocket payments for medical procedures frequently remind patients of the financial consequences of their insurance, but the missing returns on one’s retirement assets are not observed without explicit comparison to the stock market or competing funds. Most people do not compare their pension plan to the market, so even in retirement may not know what their (counterfactual) wealth would have been had they chosen a better fund .

If it is lack of attention that causes the bad choice of mutual and pension funds, then one solution (proposed by my friend Hongyu Zhang) is to make the management fees more salient by requiring their explicit payment. For example, every month the customer has to transfer the amount of the management fee from their bank account to the fund. Financially, this is equivalent to the fee being deducted from the retirement assets like now (assuming these assets are eventually taxed the same as income, otherwise the transferred fee can be adjusted to make it financially equivalent to the deduction). The attention required is however greater for an explicit payment than for doing nothing following a lack of capital gains. Similarly, requiring customers to pay the difference between the return of their fund and the market return into the fund every two weeks would nudge them towards greater attention to their retirement account.

In practice, such a nudge is unfortunately politically infeasible. Not only would the fund industry lobby against it, but voters would irrationally perceive the required explicit payments as increased taxes. This would make the transition to transferring fees to funds from customers’ bank accounts very unpopular. If people understood the equivalence between low returns on their assets and explicit payments required of them, then they would be financially literate enough to choose low-fee, high-return index funds in the first place. Thus the problem of low-performing pension funds would be absent. To sum up, the fool and his money are soon separated, and it is difficult to protect people from their own bad decisions.

Why research with more authors gets cited more

Empirically, articles with more authors are cited more, according to Wuchty et al. (2007). The reasons may be good or bad. A good reason is that coauthored papers may have higher quality, e.g. due to division of labour increasing the efficiency of knowledge production. I propose the following bad reasons, independent of potential quality differences between coauthored and solo articles. Suppose that researchers cite the works of their friends more frequently than warranted. A given scientist is more likely to have a friend among the authors of an article with a greater number of collaborators, which increases its probability of getting a „friendly citation”.

Another reason is defensive citing, i.e. including relatively unrelated papers in the reference list before submitting to a journal, in case the referees happen to be the authors of those works. The reason for adding these unnecessary citations is the belief, warranted or not, that a referee is more likely to recommend acceptance of a paper if it cites the referee’s publications. The probability that the set of referees overlaps with the set of authors of a given prior work increases in the number of authors of that work. Thus defensive citing is more effective when targeted to collaborative instead of solo papers.

The referees may also directly ask the author to cite certain papers in the revision (I have had this experience). If the referees are more likely to request citations to their own or their coauthors’ work, then articles with more authors are again referenced more.

Valderas et al. (2007) offer some additional explanations. One is measurement error. Suppose that letters to the editor, annual reports of the learned society, its presidential inaugural addresses, and other non-research in scientific journals are counted as publications. These have both fewer authors and citations than regular research articles, which creates a positive correlation between the popularity of a piece of writing and its number of authors.

If self-citations are not excluded and researchers cite their own work more frequently than that of others, then papers with more authors get cited more.

Articles with more collaborators are presented more frequently, thus their existence is more widely known. Awareness of a work is a prerequisite of citing it, so the wider circulation of multi-author publications gives them a greater likelihood of being referenced, independent of quality.

Pill testing, placebos and illegal market efficiency

Testing illegal drugs for the active ingredient differs from testing for poisonous adulterants. Both tests have opposite effects on drug use before and after buying. After the pill has been purchased, testing reduces use, because sometimes the drug fails the test, whether correctly or not, and is discarded. Before purchase, the option to test for and avoid adulterated or inactive drugs reduces the buyer’s risk, thus increases use.

In the longer term, testing benefits the dealers of purer, more predictable and less toxic drugs, putting some suppliers of fakes out of business. Pill predictability reduces overdoses – a health effect similar to lower toxicity. If old drugs can be tested, but new ones not, then buyers experiment less and the incentive to invent new narcotics decreases.

The avoidance of poisonous adulterants is good for public health, but purer pills not necessarily so. Inactive drugs undermine consumer confidence in the illegal market, reducing use, prices and casual purchases. Trust then requires a long-running relationship with the seller, which has multiple benefits. It motivates dealers to care about the health of their loyal customers, simplifies policing and gives researchers and social workers better long-term access to the at-risk population.

One claimed benefit of party drugs is that they reduce anxiety, increase the user’s confidence and social interaction, thus improving mental health. Evidence from psychiatric medicines suggests that many such benefits are due to the placebo effect. Users are quite inaccurate in estimating the purity of ingested drugs, and factors like price and place of purchase strongly influence their perception of purity. The price per pure gram is negatively related to purity in some markets, further supporting the placebo interpretation. If inactive pills boost confidence similarly to illegal drugs, then there is a clear case for flooding the market with harmless placebos. The availability of pill tests for the active ingredient reduces this opportunity to make the illegal market inefficient. Tests for toxic adulterants, however, actually favour harmless placebos.

Recording speaking time to prevent meetings from running over

To prevent meetings from running over because some people like to listen to their own voice, one way is to publish how much of others’ time each participant took. Measuring the talking time and making the results public helps participants with low self-awareness realise how long they talked, and creates social disapproval of those who go on for too long, potentially motivating them to be more concise.

A related method to prevent time overruns using current meeting rules, e.g. Robert’s Rules, is to allocate each speaker a fixed amount of time in advance. The problem with this method is the lax enforcement both during and after the meeting. If a speaker goes over and does not respond to requests to stop, then the moderator or chairperson usually does not shut the speaker up (turn off the microphone, forcefully remove the waffler from the stage, clamp a hand over their mouth). After the meeting, the possible sanctions (e.g. not inviting the speaker to future meetings, monetary fine, opposing the speaker’s proposed policy) are also infrequent or weak. Of course this enforcement problem also arises when talk time is recorded and published. However, the clear measurement removes one excuse of the speakers going over, namely their flat denial that they took more time than allocated, or more than others.

Public time-recording is especially helpful in less formal meetings that have no moderator or chairperson keeping time and notifying speakers to stop, and in meetings where a speaker is powerful enough that other participants are reluctant to interrupt with reminders of the time limit. A timekeeper is not needed to record the duration of a speech nowadays, because smartphones can identify a person based on their voice and calculate the time for which each voice spoke. There is a business opportunity in developing an app that identifies the number and timing of the speakers. The resulting data could also be used for research into social dynamics, e.g. whether some age, gender or race groups speak less, whether people in positions of power talk and interrupt more.

A smartphone app can also play a notification sound when a speaker’s time is up, eliminating the problem that the less powerful participants do not remind an important speaker to stop. In large meetings with a microphone, a computer keeping track of speech durations can force a speaker to stop by cutting power to the microphone when the time is up. A computer may be attached to other means to stop a speaker from unreasonably taking others’ time, e.g. it may draw the stage curtain, turn off the stage lights or start noise-cancelling the speech.

Spam deterrence by boycotting

The obvious reason for spam of any kind (emails, texts, phone calls, unsolicited mail) is that it is profitable. Thus spam must raise the probability that its target buys or otherwise complies with the spammer’s wishes, e.g. leaves a review. To deter spam, the incentive for it must be reversed – the targeted people should not give in to spammers, but do the opposite (not buy, not leave a review when receiving a „reminder”). I try to follow this strategy. If I remember that a business spammed me, then I try to boycott it, unless it is by far the best option (usually not, spammers are typically shady businesses and bottom-feeders).

Incentives are created by the difference in payoffs, not their level. Thus to deter spam, the buying probability should be lower for a spamming business than for a non-spamming competitor. To create this payoff difference for non-monetary actions, e.g. reviewinig, I leave a review with positive probability when not asked to do so, but certainly avoid reviewing when spammed with reminders.

If the whole society followed the strategy of boycotting spammers, then one possible concern is that spammers would start to use reverse psychology. They would spam in the name of their competitors to make them look like spammers. If customers start boycotting the competitors as a result, then demand shifts to the spammer, which is profitable.

The reverse psychology is unlikely to become a serious problem, because there are typically many competitors and the spammer would have to make most of them look bad to increase its demand significantly. Also, the law usually punishes the use of a fake name more harshly than unsolicited contacting. The competitors whose reputation is tarnished by spam under their name have a stronger incentive to sue its source than consumers just annoyed by the spam.

Pre-selected health insurance plans for visitors

A half-year visit to a US university under a J1 visa requires US health insurance. In the University of Pennsylvania, the website of the International Students’ and Scholars’ Office says that they have pre-selected some health insurance plans. According to their cover description and comparison websites, these plans offer significantly less cover than similarly-priced plans not pre-selected by U Penn. My spreadsheet comparing the health insurance options is public. Possibly I have missed some aspects of insurance that justify the price difference. Another explanation is that the pre-selection was done by people who do not themselves use these insurance plans (because they are not visitors to the US) and have little incentive to make an effort to choose the best plan. A more negative and less likely interpretation is that the insurance company is providing incentives (such as kickbacks) for the selectors at U Penn to direct visitors to expensive low-cover plans that are profitable for the insurer.

Avoiding an animal on the road

When a bike or car heads towards a squirrel, the squirrel first dodges to one side and then runs away in the other direction. Birds fly directly away from the oncoming vehicle, so stay in front of the vehicle for a few seconds. These behaviours are presumably evolutionary adaptations to avoid predators. For example, the squirrel’s dodge probably misleads a predator to alter course in the direction of the dodge. The larger predator then has more difficulty than a small agile squirrel in switching direction to the opposite side of the dodge.
In avoiding vehicles, these escape patterns are counterproductive. A predator tries to collide with the prey, but a vehicle tries to avoid collision. A squirrel’s dodge confuses the driver or cyclist, who then tries to pass the animal on the opposite side of the initial feint, which is exactly the direction the animal ends up running in. The best way to avoid collision may be to just keep going in a straight line and let the animal dodge out of the way. A constant direction and speed is easy to predict, which lets the animal avoid being in the same place at the same time as the vehicle. Keeping one’s course and speed also avoids accident-prone sharp turns and sudden stopping.
If a predator was smart and knew about the dodging behaviour, then it would go opposite the initial dodge. But then the squirrel would benefit from not switching direction. In response to the squirrel just running in one direction, the predator should run in the direction of the squirrel’s initial movement, etc. This game only has a mixed strategy equilibrium where the squirrel randomises its direction and whether it dodges or not, and the predator randomises its response to the squirrel’s initial movement direction. Dodging takes more energy than just running to one side, so the dodge must have a benefit that outweighs the energy cost, which means that the predator must be less successful when the squirrel dodges. Some factor must make it difficult for the predator to swerve opposite the squirrel’s initial direction. For example, if most prey keep running in one direction instead of feinting, then the predator may be on average more successful when following the initial movement of the prey. The cognitive cost of distinguishing squirrels from other prey must be too large to develop a different strategy for chasing squirrels.
The same game describes dribbling in soccer to avoid a defender. It would be interesting to look at data on what proportion of the time the attacker feints to one side and then moves to the other, as opposed to just trying to pass around the defender in the initial movement direction. It is more difficult for both players to switch than to keep moving in one direction, but presumably the player with the ball finds it relatively more complicated than the defender. In this case, to keep the other player indifferent, each player only has to switch direction less than half of the time, but the defender relatively less frequently. If the attacker feints and the defender does not switch direction, then the defender looks clumsy and the attacker a good dribbler. Reputation concerns of soccer players (who are after all entertainers) may make them switch direction more often than a pure winning motive would dictate.
Similarly, soccer players may use flashy moves like scissor kicks more often than is optimal for winning, because the flashiness makes the player popular with fans.

Neighbourhood coordinating to keep houses small and prices high

If apartment buildings are built in a neighbourhood of detached houses, then the house prices fall, especially next to the new apartment buildings. There is less privacy in the garden if many windows overlook it, and there is more congestion and crime if more people live nearby. The neighbourhood’s common interest may be to block the development of large buildings in it. However, an individual homeowner finds it profitable to sell to a property developer who will replace the detached house with a large apartment building, because the cost of reduced house prices is borne by the neighbours, not by the seller.
One way that neighbourhoods try to prevent this tragedy of the commons is to require all homeowners to join an association and agree to be bound by the rule that the association can prohibit new buildings or expansions. Such rule-based solutions are usually vulnerable to legal loopholes and changes in government policy that invalidate the restrictions. Game theory offers a solution without requiring any external enforcement: if one homeowner extends her house or replaces it with a bigger building, or sells to someone who will, then the neighbours respond by building apartment buildings around the property of the first breaker of the social norm of non-expansion. Then the view from the first expanded building is only the walls of the others, which makes the expansion unprofitable and deters enlargement in the first place.
The punishment for the first extension has to be certain enough to deter it. In particular, the homeowners next to the violator of the norm must be incentivised to build even at a loss. This incentive can be provided by requiring the neighbours of the homeowners next to the violator to punish those who do not punish the violator. This punishment can again be the development of large buildings next to their property. Those who refuse to punish the non-punishers can be punished the same way, etc, in concentric circles around the original violator.
The incentives provided by dynamic games such as this one may seem strange, but can be easily coordinated by a homeowners’ association without any legal power. The association simply publishes the rule that (a) enlargement of current buildings or the construction of new ones is forbidden and (b) if someone breaks the rule, then any new construction in a specified radius around the first rule-breaker is allowed. If one enlargement or new building is profitable, then typically a few extensions next to it are also profitable. The fewer neighbours of the first rule-breaker that build bigger houses as punishment, the more profitable an extension is for any neighbour. So some neighbours will punish the first violator. This will make the house prices of other neighbours fall, which reduces the cost to them of selling their houses to property developers for apartment building construction, i.e. reduces the cost of punishing the original rule-breaker.

Buildings replaced quickly, so built badly

In a fast-growing city, many buildings will be replaced by larger ones in a decade or two. Property developers probably take this into account, thus do not hesitate to build low-quality non-durable housing. If the city growth stops at some point and buildings are no longer quickly replaced, then the owners of such housing will get an unpleasant surprise.
People buying or building detached houses do not seem to take city growth into account, because at least in Canberra, I see the erection of large expensive mansions in districts where the house will in 20-30 years be surrounded by high apartment buildings. Tall structures around a mansion tend to reduce its value, and certainly make the garden less private. The investment in fancy gardens, backyard swimming pools, etc, seems a bit short-sighted in locations close to the centre of a growing city.
The mansions also fill most of the plot of land on which they stand, so from an energy efficiency point of view, they might as well join walls with neighbours, as I have written before.