Category Archives: Uncategorized

Silly balconies

Everywhere in Australia, I have seen buildings with balconies that overlook busy roads. The view from the balcony often only includes other buildings. These balconies seem useless, because not many people want to sit in the street noise and car exhaust. I have rarely seen anyone on these balconies, and then only moving around for a practical purpose, not enjoying the air and view. Mostly the balconies are used for storing unwanted furniture and sports equipment, or growing potted plants. This makes sense, because even drying laundry over a busy road is problematic – everything gets covered in fine black soot. What does not make sense is adding these balconies to the buildings in the first place. A more practical use of the space would be to close the open parts of the balcony and thus add an extra room to the apartment. It is used as a storage room anyway.

In some cases, the building might have been constructed before the street became too busy or the views blocked by other buildings, but most of the buildings with balconies are new, so this explanation does not apply.

The reason the developers add balconies to their buildings is probably to market the apartments to impractical people. An included balcony makes the apartment sound more luxurious, and usually the view and relaxation opportunities of the balcony are touted in the advertisement. But people inspect the apartment before buying, so they should see the uselessness of the balcony for anything but storage. Inspections are usually scheduled on Saturdays when there is less traffic, and the inspecting buyers don’t sit on the balcony for long enough to become annoyed by the noise and the car exhaust.

There may be rules against the owner of an apartment closing up the balcony to create a room, because this makes the building facade uneven. Coordination problems between apartment owners may prevent them from closing up all the balconies of the building simultaneously.

Defence against bullying

Humans are social animals. For evolutionary reasons, they feel bad when their social group excludes, bullies or opposes them. Physical bullying and theft or vandalism of possessions have real consequences and cannot be countered purely in the mind. However, the real consequences are usually provable to the authorities, which makes it easier to punish the bullies and demand compensation. Psychological reasons may prevent the victim from asking the authorities to help. Verbal bullying has an effect only via psychology, because vibrations of air from the larynx or written symbols cannot hurt a human physically.

One psychological defense is diversification of group memberships. The goal is to prevent exclusion from most of one’s social network. If a person belongs to only one group in society, then losing the support of its members feels very significant. Being part of many circles means that exclusion from one group can be immediately compensated by spending more time in others.

Bullies instinctively understand that their victims can strengthen themselves by diversifying their connections, so bullies try to cut a victim’s other social ties. The beaters of family members forbid their family from having other friends or going to social events. School bullies mock a victim’s friends to drive them away and weaken the victim’s connection to them. Dictators create paranoia against foreigners, accusing them of spying and sabotage.

When a person has already been excluded from most of their social network, joining new groups or lobbying for readmission to old ones may be hard. People prefer to interact with those who display positive emotions. The negative emotions caused by a feeling of abandonment make it difficult to present a happy and fun image to others. Also, if the „admission committee” knows that a candidate to join their group has no other options, then they are likely to be more demanding, in terms of requiring favours or conformity to the group norms. Bargaining power depends on what each side gets when the negotiations break down – the better the outside option, the stronger the bargaining position. It is thus helpful to prepare for potential future exclusion in advance by joining many groups. Diversifying one’s memberships before the alternative groups become necessary is insurance. One should keep one’s options open, which argues for living in a bigger city, exploring different cultures both online and the real world, and not burning bridges with people who at some point excluded or otherwise acted against one.

There may be a case for forgiving bullies if they take enough nice actions to compensate. Apologetic words alone do not cancel actions, as discussed elsewhere (http://sanderheinsalu.com/ajaveeb/?p=556). Forgiving does not mean forgetting, because past behaviour is informative about future actions, and social interactions are a dynamic game. The entire sharing economy (carsharing, home-renting) is made possible by having people’s reputations follow them even if they try to escape the consequences of their past deeds. The difficulty of evading consequences motivates better behaviour. The same holds in social interactions. In the long run, it is better for everyone, except perhaps the worst people, if past deeds are rewarded or punished as they deserve. If bullying is not punished, then the perpetrators learn this and intensify their oppression in the future.

Of course, the bullies may try to punish those who reported them to the authorities. The threat to retaliate against whistleblowers shows fear of punishment, because people who do not care about the consequences would not bother threatening. The whistleblower can in turn threaten the bullies with reporting to the authorities if the bullies punish the original whistleblowing. The bullies can threaten to punish this second report, and the whistleblower threaten to punish the bullies’ second retaliation, etc. The bullying and reporting is a repeated interaction and has multiple equilibria. One equilibrium is that the bullies rule, therefore nobody dares to report them, and due to not being reported, they continue to rule. Another equilibrium is that any bullying is swiftly reported and punished, so the bullies do not even dare to start the bullying-reporting-retaliation cycle. The bullies rationally try to push the interaction towards the equilibrium where they rule. Victims and goodhearted bystanders should realise this and work towards the other equilibrium by immediately reporting any bullying against anyone, not just oneself.

To prevent insults from creating negative emotions, one should remember that the opinion of only a few other people at one point in time contains little information. Feedback is useful for improving oneself, and insults are a kind of feedback, but a more accurate measure of one’s capabilities is usually available. This takes the form of numerical performance indicators at work, studies, sports and various other tests in life. If people’s opinions are taken as feedback, then one should endeavour to survey a statistically meaningful sample of these opinions. The sample should be large and representative of society – the people surveyed should belong to many different groups.

If some people repeatedly insult one, then one should remember that the meaning of sounds or symbols that people produce (called language) is a social norm. If the society agrees on a different meaning for a given sound, then that sound starts to mean what the people agreed. Meaning is endogenous – it depends on how people choose to use language. On an individual level, if a person consistently mispronounces a word, then others learn what that unusual sound from that person means. Small groups can form their own slang, using words to denote meanings differently from the rest of society. Applying this insight to bullying, if others frequently use an insulting word to refer to a person, then that word starts to mean that person, not the negative thing that it originally meant. So one should not interpret an insulting word in a way that makes one feel bad. The actual meaning is neutral, just the „name” of a particular individual in the subgroup of bullies. Of course, in future interactions one should not forget the insulters’ attempt to make one feel bad.

To learn the real meaning of a word, as used by a specific person, one should Bayes update based on the connection of that person’s words and actions. This also helps in understanding politics. If transfers from the rich to the poor are called „help to the needy” by one party and „welfare” by another, then these phrases by the respective parties should be interpreted as „transfers from the rich to the poor”. If a politician frequently says the opposite of the truth, then his or her statements should be flipped (negation inserted) to derive their real meaning. Bayesian updating also explains why verbal apologies are usually nothing compared to actions.

Practicing acting in a drama club helps to understand that words often do not have content. Their effect is just in people’s minds. Mock confrontations in a play will train a person to handle real disputes.

Learning takes time and practice, including learning how to defend against bullying and ignore insults. Successfully resisting will train one to resist better. Dealing with adversity is sometimes called „building character”. To deliberately train oneself to ignore insults, one may organise an insult competition – if the insulted person reacts emotionally, then the insulter wins, otherwise the insulter loses. As with any training and competition, the difficulty level should be adjusted for ability and experience.

The current trend towards protecting children from even verbal bullying, and preventing undergraduate students from hearing statements that may distress them could backfire. If they are not trained to resist bullying and experience it at some point in their life, which seems likely, then they may be depressed for a long time or overreact to trivial insults. The analogy is living in an environment with too few microbes, which does not build immunity and causes allergy. „Safe spaces” and using only mild words are like disinfecting everything.

The bullies themselves are human, thus social animals, and feel negative emotions when excluded or ignored. If there are many victims and few bullies, then the victims should band together and exclude the bullies in turn. One force preventing this is that the victims see the bullies as the „cool kids” (attractive, rich, strong) and want their approval. The victims see other victims as „losers” or „outsiders” and help victimise them, and the other victims respond in kind. The outsiders do not understand that what counts as „cool” is often a social norm. If the majority thinks behaviour, clothing or slang A cool, then A is cool, but if the majority agrees on B, then B is preferred. The outsiders face a coordination game: if they could agree on a new social norm, then their number being larger than the number of insiders would spread the new norm. The outsiders would become the „cool kids” themselves, and the previously cool insiders would become the excluded outsiders.

Finding new friends helps increase the number who spread one’s preferred norms, as well as insuring against future exclusion by any subset of one’s acquaintances.

If there are many people to choose from when forming new connections, then the links should be chosen strategically. People imitate their peers, so choosing those with good habits as one’s friends helps one acquire these habits oneself. Having friends who exercise, study and have a good work ethic increases one’s future fitness, education and professional success. Criminal, smoking, racist friends nudge one towards similar behaviours and values. Choosing friends is thus a game with one’s future self. The goal is to direct the future self to a path preferred by the current self. The future self in turn directs its future selves. It takes time and effort to replace one’s friends, so there is a switching cost in one’s social network choice. A bad decision in the past may have an impact for a long time.

It may be difficult to determine who is a good person and who is not. Forming a social connection and subtly testing a person may be the only way to find out their true face. For example, telling them a fake secret and asking them not to tell anyone, then observing whether the information leaks. One should watch how one’s friends behave towards others, not just oneself. There is a tradeoff between learning about more people and interacting with only good people. The more connections one forms, the greater the likelihood that some are with bad people, but the more one learns. This is strategic experimentation in a dynamic environment.

Conferences and seminars as cargo cults

I wrote about the wastefulness of physically travelling to conferences or to give seminars, because one could give a presentation via a video call over the internet (http://sanderheinsalu.com/ajaveeb/?p=442). Other than habit or tradition, why would scientists organise conferences and seminars with physical attendance? One explanation I offered was that physical presence is a commitment device. Herding is another justification to any tradition. Irrationality is a third, which complements herding.

Holding conferences and seminars may be rational if top researchers are presenting and providing feedback, because there is much to learn from them. Such workshops may not be useful if the participants are not on the research frontier. Nonetheless, the low-achievers may organise such gatherings, because they want to publish like the high-achievers, and they perceive that the high-achievers benefit from the research meetings of large groups. A cargo cult means imitating someone’s behaviour to reach the same goals as them, but without understanding the reason why their actions lead to the results they do. The lack of comprehension of the underlying mechanism leads the imitation subtly astray, so it does not obtain the desired results. The conferences and seminars of low-achievers are a cargo cult if the following hold: only the participation of high-achievers makes research meetups useful, the high-achievers do not attend low-prestige meetups, and the low-achievers do not understand the above. It is difficult to test the usefulness of any action in research, because publication success is noisy, influenced by many factors and with long delays. Thus it is difficult to test whether there is a cargo cult in the less advanced levels of the research community.

Besides improving quality, the feedback of top researchers can increase publication chances by making the research of those lower in the scientific hierarchy conform to the tastes of the top. This is a horizontal differentiation effect – matching idiosyncratic tastes. It is not vertical differentiation (improving quality). If top people as referees and editors favour a certain field of research or ideology, then presenting work to them may uncover their biases and enable an author to pander to them.

Another way that presenting helps with publication is the familiarity effect. When the referee or editor has seen the paper presented before reading it, then the content is familiar and thus easier to understand. The reader may interpret the ease of comprehension as clarity of the paper, not familiarity of the material. Clear writing and well-structured ideas are a positive signal to the referee and increase the publication chances.

If the second-best people imitate the highest-achievers, then the third-best may imitate the second-best, etc. The cargo cults may be multilayered. Such imitation of imitators is called herding. It may sometimes be individually rational, but may lead to socially suboptimal ignoring of later information in favour of imitating the decisions of those who acted based on earlier info. Herding strengthens the effects of mistaken imitation, thus worsening cargo cult effects.

Cargo cults occur widely – any time there is a fad, fashion or bubble, some people jump on the bandwagon because their role models did, without asking why the role models did so. The personal situation of the trailbreakers may make it rational for them to act in a certain way, but the different circumstances of the followers may make imitation counterproductive for them. An example is creating a financial bubble to profit from it (pump-and-dump strategy). The starters profit from the amount invested by the followers. The last people to become followers lose their investment when the bubble bursts. I am not the first to compare the research community to a pyramid scheme – search „Profzi scheme” online.

Remembering the sacrifice

Many times and in many places I have seen a call to remember the sacrifice of the soldiers who died in some past conflict. Often, this call seems an attempt to direct attention away from the misguidedness of the particular conflict or the incompetence and selfish motives of the leadership who decided to enter the war. It tries to make people focus on the noble courage of the soldiers, not the sordid power-hunger of the rulers. The bravery of soldiers is discussed in another post (http://sanderheinsalu.com/ajaveeb/?p=595); here I would like to clarify this sacrifice business.

If the soldiers volunteered under reasonably accurate information about the reasons for the conflict and the chances of success, then indeed they chose to sacrifice themselves for the cause. Then we should remember their sacrifice. If, however, they were conscripted (dictatorships often call this volunteering) using the threat of punishment for them or their family, then they did not make the sacrifice any more than a sacrificial animal sacrifices itself. Others sacrificed the conscripts to further their own ends.

These ends are unlikely to prioritize defeating an evil regime and making the world a better place, although the propaganda claims this was the objective. Mostly the goal of leaders is to preserve and expand their power, whether by defending the country against takeover or conquering additional subjects and wealth. Even if this is acknowledged, current propaganda may point out some good side effect of sacrificing the soldiers, e.g. defeating an old enemy. This is again a distraction attempt. The world is complex and interconnected, so every event, including a mass death, has some beneficial side effects, just like every event has some negative side effects. One should consider the overall consequences of an event, not just one side effect.

If the soldiers genuinely volunteered, but due to being misled by propaganda, then they wanted to sacrifice themselves for one cause, but their leaders sacrificed them for another. Usually volunteers underestimate the length of the war and the probability of dying. Thus even when they know the true goal of the conflict, the sacrifice they are led to is larger than the one they intended to make.

The most clear and direct self-sacrifice is made by suicide bombers. They probably think that their bombing serves a good purpose, but such belief is almost always misguided. Religious indoctrination of the bombers manipulates them into believing in a noble cause, hiding the true goals of the leaders ordering the bombing.

I have not heard many calls to remember the sacrifice of present-day child soldiers. Rather there are calls to pity and save them. The situation of many soldiers in many wars has been similar to children forced to fight – ignorance and fear of punishment. Obeying the conscription order often offers a greater survival probability than refusal.

Instead of remembering the sacrifice of conscripts, we should remember them being sacrificed. Remember with pity. Remember to prevent.

Would a protest influence you?

Help, a politician I don’t like is in power! I should do something about it. But what? I know! I will join a protest – this is something. Now I can feel good about myself for having done something. And post on social media how I opposed evil so effectively. I am a socially conscious, altrustic person.

On a more serious note, one way to evaluate whether a given protest could change the situation is to put yourself in the position of the target audience. If your favourite politician was in power, would this protest change your support for said politician? If you were the politician in power, would you change your policy when many opponents use this protest against it?

Even if the answer is no, a protest may still have some effect, because it may change the preferences of the swing voters. The „no” may come from deeply ideological people, whereas more open-minded folks may conform to the herd. If they see many people opposed to something, they may start to oppose it too.

On the other hand, a protest may have the opposite effect to the one intended. It may harden ideological positions and increase polarisation. If the majority is weakly in favour of a policy, then protests against it may strengthen the support of the majority for it, leading to greater turnout and more yes-votes.

From an economic viewpoint, marching on the street with signs, chanting slogans or commenting on social media has no direct impact on politicians or most voters. The exception is those who are stuck in a traffic jam when a protest closes a street. Rational agents should not pay attention to protests which do not affect them (such activism is „cheap talk” in economic jargon, or at best „money burning”).

Real people may be swayed by the opinion of a large crowd. However, a form of protest that has an objective impact on people’s lives is likely to influence people more, because it affects them via both the opinion of the crowd and the direct impact. Both the belief shift and the hardening of the opposition are probably greater.

There are many illegal means of directly affecting the population, but also some legal forms of protest with objective impact. Economic protest is boycotting certain countries, firms or goods, refusing to work for the regime, and moving elsewhere („voting with one’s feet”), and is usually legal. The objective impact is that if enough intelligent and hardworking people shift their spending and taxpaying elsewhere, then the regime will be in fiscal trouble. If this does not change the policy of the leadership, then at least the lack of money will make the program harder to carry out.

There is a larger personal cost for economic protest than for cheap talk. One has to give up certain goods, or pay more, or experience the hassle of moving residence. This is why most people who threaten to boycott a firm or leave a country do not end up doing so. The threats are just another form of cheap talk, which can be posted on social media to impress other cheap talkers.

Incentivising refereeing

To shorten the refereeing lag and improve report quality in economics, the natural solution is to incentivise academics to do a better and quicker job. Economists respond to incentives, but currently no salary or promotion consequences arise from good or bad refereeing, as far as I know. In http://sanderheinsalu.com/ajaveeb/?p=503, I wrote about incentives for authors not to submit careless papers (in the hope that a refereeing mistake gets them accepted). One such incentive is requiring refereeing for a journal as a precondition for submitting to that journal. If a submitted paper gets n referee reports on average, then before submitting, an author should referee n papers in a timely manner, which should balance the supply and demand of refereeing. This forced refereeing may lead to quick, but sloppy reports.

An additional incentive is needed for quality. Rahman’s 2010 paper on the question „who watches the watchmen” suggests an answer. The editor can insert a deliberate mistake in every paper and see whether a referee finds it. If not, then the refereeing of that person is likely of low quality. The mistake is corrected before publication. Alternatively, the editor can ask each author to insert a mistake and tell the editor about it. The author is not penalised for this mistake and is asked to correct it if the paper is accepted. The referees are again judged on whether they find the mistake.

The above scheme derives refereeing incentives from publication incentives, requiring minimal change to the current system. However, it is somewhat indirect. A more straightforward incentive for refereeing is to reward it directly, either paying for it or basing promotion decisions partly on it. The speed of refereeing is already slightly monetarily incentivised in the American Economic Journal: Microeconomics. If the referee sends the report before a deadline, then she or he is paid 100 dollars. If a good referee report takes about 10 hours, then the amount is certainly not enough to motivate quality provision, but it is a step in one of the right directions. A simple improvement on the binary „before vs after deadline” reward scheme is to reduce the payment gradually as the delay of the referee report increases.

If refereeing is incentivised, then lower-ranked journals need larger incentives to compensate for the fact that refereeing for these has less inherent prestige and the paper one has to read is of lower quality. On the other hand, lower-ranked journals are less able to motivate refereeing with the threat of not accepting submissions from those who have not refereed. There are more lower-ranked journals, and it is less important to get accepted by any particular one of them. Some of the less prestigious journals would find no referees under the system proposed above. This is good, because it removes the „peer reviewed” status of some junk journals and may force them to close. If authors know that quality journals require refereeing before submission, then they draw the obvious conclusion about a journal that does not require it.

On military bravery

All countries and armed groups emphasize the bravery of their soldiers for propaganda purposes. Such claims are made regardless of whether there is any actual valour. Going to a dangerous situation or even certain death is not necessarily courageous, in particular if there is no knowledge of the danger or no choice. Are sheep going into a slaughterhouse brave? They are calmly walking to certain death, after all. But usually this is not ascribed to courage, but to ignorance. Analogously, soldiers used in early tests of the physiological effects of radiation exposure who were marched through an area of a recent nuclear explosion are not considered brave. They did not know the cancer risk.

If there is no choice, which usually means there are only perilous choices, then putting oneself in danger is not usually accounted brave. Jumping out of a burning building offers a higher probability of survival, so people do it despite the substantial risk of falling to death. When a sufferer of a painful terminal disease chooses euthanasia, this early death is commonly not considered brave. Some cultures even believe suicide to be a sign of cowardice. If a military has a well organized system for catching deserters and administering the death penalty to them (and their family in some regimes), then a soldier charging enemy machineguns is merely maximizing his survival probability. The enemy might miss, the firing squad rarely does.

The greater the probability of victory for one’s own side, the less attractive desertion becomes, because being caught is more likely. This explains the propaganda emphasis on own victories and the punishment of “defeatist talk” in wartime. The greater the military advantage of a party in an armed conflict, the less bravery its soldiers need.

Genuine bravery exists, but it is rare. Evolution favours cowardly bullies who attack the weaker (prey) and run from the stronger (predators). People who face no compulsion to fight in a war and know the dangers, yet still join, are brave. Freedom fighters (insurgents from the other side’s viewpoint) against a dictator qualify. With the caveat that only joining the fight initially requires bravery – after that, losing would mean being tortured to death by the dictator, so continuing the war is the safer option. Similarly, volunteering for the military requires some bravery (the more the greater the likelihood of being sent into danger), but once military law applies, desertion is usually more dangerous than the duty.

Military courage is proved for those who start the war as a weaker side against a stronger, if a continuing peace is not a slow death. Peasant revolts were often driven by hunger, meaning the participants may have perceived the probability of death from starvation as higher than the probability of being killed by the aristocrats.

People who have never faced an informed choice between a safe and a dangerous option may be “latently brave”, in the sense that given such a choice, they may exhibit courage. They are not proved brave, however, until they have made the choice. There are likely to be some latently brave people in the world’s militaries and armed groups. Probably a greater percentage than among the general population.

There are some proven brave folks even in the militaries of powerful countries, but the proof requires knowingly choosing a dangerous option when there is no future punishment for cowardice. For example, when nobody would know of the choice.

A topical question is whether suicide terrorists and other fighting religious fanatics are brave. Their behaviour may be driven by the fear of punishment either in the afterlife or by their fellow fanatics. It may also be due to ignorance – believing in an afterlife is like believing that one cannot really die and thus the danger is not real. In both cases, no courage is required for choosing death.

The belief in the impossibility of dying may even be literal – W.E.B. Griffin had a story of a witch doctor convincing the fighters of his tribe that his magic had made them immune to bullets. Great was the fighters’ surprise later… Their charge with spears against guns was not due to bravery, however.

On backpackers and low-spending tourists

Countries encourage tourism to make money. The same goes for local governments, tourism industry associations and tour firms. Some places provide options for low-spending tourists like backpackers, despite not making much money from them. These options may be cheap campsites, backpacker hostels, allowing hitchhiking and work-travel visas. At first sight, any positive revenue from poorer tourists would justify welcoming them. This simple revenue calculation, however, neglects the substitution effect and dynamic demand.

Substitution means that if cheaper travel options are available, then some tourists who would have spent more in the absence of these options now spend less. For example, a person who would stay in a hotel if there was no other accommodation, stays in a backpacker hostel instead. On the other hand, if all options are expensive, then the poorest tourists do not come at all. There is a tradeoff between the number of tourists and the average tourist’s spending. If introducing cheaper options leads to many tourists switching to these, but does not attract many additional low-spending people, then creating these cheaper options reduces total profit.

Dynamic demand means that a person who has toured a particular location once changes his or her likelihood of going there in the future. For example, having seen a tourist site, a person does not visit it again. Or someone going on vacation and liking the location starts going there year after year. If a region encourages young, low-income people to visit as backpackers, then it may increase or decrease future visits by these people when they are older and wealthier. In particular, if people do not tour the same location again (and spend more when older), then encouraging them to visit when young reduces the total profit from them over their lifetime.

The fact that some regions welcome backpackers has several possible explanations. There may not be much substitution, or a visit may increase future visits. The tourism industry may not have thought this through and may be reducing their own profit inadvertently. Or the government may have other objectives than taxes from the tourism industry. For example, allowing people from other countries to visit cheaply may make these people friendly to the host country, which may yield some nonmonetary benefit in international relations.

 

Putting passengers on earlier flights

If the first leg of a multi-hop flight is delayed, then the passengers on it may miss their connection. Then airlines put them on the next flight to the same destination. Or if the next flight is full, then the one after next, etc.

On the other hand, airports recommend that passengers arrive hours before their flight departs, in order to leave time for getting through security and to the gate. If the security line is short, then some people arrive at the departure area before the previous flight to their destination leaves. They would benefit from switching from their original flight to the previous one, because the wait at the airport would be shorter and they would arrive at their destination sooner. Currently, switching to an earlier flight is not allowed. However, the airlines would benefit from putting passengers on an earlier flight (if not full), because this leaves more seats open on the later flight. These seats can then be allocated to the delayed passengers from connecting flights.

The obvious question is, what if the delayed passengers need seats on the earlier flight, not the one from which people were switched to the earlier flight? The switch to a preceding flight can be decided at the departure gate just before this preceding flight leaves. In this case, any delayed passengers would already have been moved to this flight. Any optional switches of early-arriving people would have lower priority and a later decision time, so would not take seats away from any original or delayed passengers.

For the first flight of the day, the delayed people from previous flights are known hours in advance. The passengers booked on the second flight of the day to a given destination may be put on the first flight there, if they arrive before it departs. There is no worry about last-minute arrivals who may need additional seats on the first flight.

Probability of finding true love

The concept of true love has been invented by poets and other exaggerators. Evolutionarily, the optimal strategy is to settle with a good enough partner, not to seek the best in the world. But suppose for the sake of argument that a person A’s true love is another person B who exists somewhere in the world. What is the probability that A meets B?

There is no a priori reason why A and B have to be from the same country, have similar wealth or political views. Isn’t that what poets would have us believe – that love knows no boundaries, blossoms in unlikely places, etc?

Given the 7 billion people in the world, what fraction of them does a given person meet per lifetime? Depends on what is meant by “meets” – seeing each other from a distance, walking past each other on the street, looking at each other, talking casually. Let’s take literally the cliché “love at first sight” and assume that meeting means looking at each other. A person looks at a different number of people per day depending on whether they live in a city or in the countryside. There is also repetition, i.e. seeing the same person multiple times. A guess at an average number of new people a person looks at per day is 100. This times 365 times a 70-year lifespan is 2555000. Divide 7 billion by this and the odds of meeting one’s true love are thus about one in three thousand per lifetime.

Some questionable assumptions went into this conclusion, for example that the true love could be of any gender or age and that the meeting rate is 100 per day. Restricting the set candidates to a particular gender and age group proportionately lowers the number of candidates met and the total number of candidates, so leaves the conclusion unchanged.

Someone on the hunt for a partner may move to a big city, sign up for dating websites and thereby raise the meeting rate (raise number met while keeping total number constant), which would improve the odds. On the other hand, if recognizing one’s true love takes more than looking at them, e.g. a conversation, then the meeting rate could fall to less than one – how many new people per day do you have a conversation with?

Some people claim to have met their true love, at least in the hearing of their current partner. The fraction claiming this is larger than would be expected based on the calculations above. There may be cognitive dissonance at work (reinterpreting the facts so that one’s past decision looks correct). Or perhaps the perfect partner is with high probability from the same ethnic and socioeconomic background and the same high school class (this is called homophily in sociology). Then love blossoms in the most likely places.