Who discriminates whom?

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In social networks with multiple races, ethnic or religious groups involved it is generally the case that there are fewer links between groups and more within groups than would be expected from uniform random matching. One piece of research exploring this is Currarini, Jackson, Pin (2009).

When observing fewer intergroup links than equal-probability matching predicts, the natural question is who discriminates whom. If group A and group B don’t form links, then is it because group A does not want to link to B or because B does not link to A? If we observe more couples where the man is white and the woman is Asian than expected from uniform random matching, is this due to the `yellow fever’ of white men or a preference of Asian women for white men? It could also be caused by white men and Asian women meeting more frequently than other groups, but this particular kind of biased matching seems unlikely.

Assume both sides’ consent is needed for a link to form. Then the probability that a member of A and a member of B form a link is the product of the probabilities of A accepting B and B accepting A. We can interpret these probabilities as the preference of A for B and B for A and say that if the preference of A for A is stronger than the preference of A for B, then A discriminates against B. From data on undirected links alone, only the product of the probabilities can be calculated, not the separate probabilities. So based only on this data it is impossible to tell who discriminates whom.

If there are more than two groups in the society, then for each pair of groups the same problem occurs. Under the additional assumption that a person treats all other groups the same, only his own group possibly differently from the other groups, the preference of each group for each group can be calculated. This assumption is unlikely to hold in practice though.

If only one side’s consent is needed for a link to form, then from data on these directed links, the preference of each group for each group can again be calculated. The preference of A for B is just the fraction of A’s links that are to B, divided by the fraction of B in the population.

With additional data on who initiated a link or how much effort each side is putting into a link, the preference parameters may be identifiable. The online dating website OKCupid has some statistics on how likely each race is to initiate contact with each other race and how likely each race is to respond to an initial message by another race. If these statistics covered the whole population, then it would be easy to calculate who discriminates whom. In the case of a dating website however, the set of people using it is unlikely to be a representative sample of the population. This may change the results in a major way.

If the average attractiveness of group A in just the dating website (not in the whole population) is higher than that of other groups, then group A is likely to receive more initial contact attempts just because they are attractive. They can also afford to respond to fewer contact attempts since, being attractive, they can be pickier and make less effort to form links. If we disregard the nonrepresentative sample problem and just calculate the preferences of all groups for all other groups, then all groups will be found discriminating in favour of group A, and group A will be found discriminating against all others. But in the general population this may not be the case.

The attractiveness of group A in the dating website can differ from their average attractiveness if the website is more popular with group A and there is adverse selection into using the website. Adverse selection here means that only the people sufficiently unattractive to find a match by chance during their everyday life make the extra effort of starting to use the website to look for matches. So the average attractiveness of all groups using the website is lower than the population’s average attractiveness.

If a larger fraction of group A prefers to use the website and the users from all groups are drawn from the bottom end of the attractiveness distribution, then the website is relatively more popular with attractive members of A than with attractive members of other groups. Therefore the average attractiveness of those members of A using the website is higher than the average attractiveness of those members of other groups using the website. The higher preference of group A for using the website must be exogeneous, i.e. due to something other than A’s lower average attractiveness, otherwise this preference does not cause A’s attractiveness on the website to rise. It could be that members of A are more familiar with the internet, so have a lower effort cost of using any website. Or there may be a social stigma against using online dating sites, which could be smaller in group A than in other groups.

If statistics from a nonrandom sample show discrimination, there may or may not be actual discrimination in the population, depending on the bias of the sample. It could also be that the actual discrimination is larger than the sample shows, if the sample bias goes in the opposite direction from the one described above.

Trust of tourists and the tragedy of commons

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The tragedy of commons is a situation where a common resource has many users whose property rights are not precisely defined. Each user benefits from taking more of the resource, but all other users lose if one takes more. At the equilibrium level of resource use, if one user takes more, then the combined loss of the other users exceeds the gain of the one user.

The trust of tourists is like a common resource for the tourism businesses in one area. Each firm can use aggressive business practices that yield higher immediate profits, but leave tourists with a bad experience. This erodes the goodwill of tourists towards all firms in the area, so all other firms suffer because one firm cheats tourists. The cheating firm’s future profits will also be lower, but usually not by enough to deter cheating at present.

It may be an equilibrium for all firms to get as much immediate profit as they can and for tourists not to trust any firm in that area. The sum of the firms’ profits is then probably lower than in the case where they all follow good practices and the tourists trust them.

If the firms agree to use good practices and this agreement is enforceable, for example via a trade association, everyone might win. The tourists get better quality, better value for money, and the firms get higher profits. On the other hand, if the firms can agree on one thing, they can agree on another, for example a cartel. This will further increase firm profits, but will lower value for money of tourists. The overall effect of an agreement among firms on the benefit tourists get is uncertain.

Why politics is as it is and how to change it

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Politics in all democratic countries is dishonest, propagandistic, riven by special interests etc. From time to time politicians who promise to change this arise. Mostly these politicians fall into the old ways and create no change but sometimes they turn their countries into dictatorships.

It is very difficult to change the way politics is done because there is a reason why politics is the way it is. Not many people set out to lie and cheat their way to the top. Mostly they start with good intentions but gradually adopt the tactics generally used.

The reason for dishonesty is that politics is an evolutionary process (mutation, selection, reproduction). People invent new ways to manipulate others all the time (mutation). Those who use the kind of tactics generally used in modern politics are likely to get elected (selection). Their tactics are then copied by the next generation of politicians (reproduction). The end result is a thoroughly dishonest political class because lying and cheating work as ways to get to the top. There is no lack of idealists trying to do honest politics but mostly they won’t get elected because their restriction to honest methods severely limits the crowd-manipulation tools available to them. If they do get elected, they will be outnumbered by the dishonest ones.

 

Proposed method of change

Trying to get enough honest politicians elected to change the system just won’t work because honesty limits their tools of making people elect them. Politicians use dishonesty because it works and gets them power.

In a democracy the power ultimately rests with the people. If all people or even just a bare majority were rational and perfectly informed, there would be no room for manipulation and dishonesty. The present political situation is only possible because people are stupid enough to be manipulated into electing the people who create such a political situation. Every nation deserves its leaders.

The way to lessen dishonesty in politics is to make people recognize and dislike it. Most people are not clever enough to see through the manipulation themselves, so the media and perhaps scientists should help them.

When televising speeches of politicians the news agencies could place a running commentary on the speech in the subtitles, pointing out logically or factually wrong statements, demagogy and meaningless phrases, giving examples of the politician’s possible motives for saying certain things, pointing out the interest group to whom a promise is aimed.

The news agencies could keep a file on every politician of sufficient influence. The file should contain their earlier promises, statements, voting record and press releases. Every time the news agency runs a story containing that politician the online version of the story should have a link to that politician’s file. If the politician contradicts his or her earlier talk, it should be pointed out by the news agency and a link to the appropriate place in that politician’s file placed next to the reference.

People could be educated in basic mathematical logic so they could notice some logically false statements (one can never teach most people enough to make them recognize factually wrong claims, that is what the politician’s file would be for).

In countries where a certain number of citizens can initiate laws, those interested in honest politics could campaign for a law recalling a politician who has lied. Then a referendum can be organized to pass that law because politicians themselves certainly would not do it. Lying would need to be clearly defined in the law so that uncertain statements and slips of the tongue would not empty all government institutions. In some cases, however, it can certainly be proved that what the politician said contradicts the facts or is logically false.

Suggested questions for admitted graduate students

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For people admitted to PhD programs in economics, here are some suggested questions to get answers to before choosing the program.

Answers from online search and other sources

What is the ratio of faculty members to students?

How many faculty members does the department have in the field you are interested in? Count only those whose primary field that is, not the ones who once wrote one paper in it or who hang out at the seminars for the free food.

How many years and how many hours a week are students expected to TA during their program?

What is the ratio of students on the job market to the size of the incoming class?  Equivalently how many students were mysteriously lost in the grad school process? Average across multiple years if possible.

Answers from faculty members

How many hours a week do you spend advising graduate students (reading their work, talking to them about their research)?

How many hours a week are graduate students expected to spend on TAing?

Answers from graduate students

How many hours per week or month do faculty members advise you (read your work, talk to you about your research)? Use the number of graduate students (perhaps exclude first and second years) and faculty members in the department to compare answers to this question from faculty members and graduate students.

How many hours per week are you supposed to spend on TAing and how many do you actually spend? Compare the student answer to the faculty answer.

What is the average number of years students take to reach the job market? What is the length of the stipend? How hard is it to get campus jobs (TAing, RAing) that pay for living costs after the stipend ends?

How many students are kicked out after the first year? How many in each year leave without a PhD after passing the first year exams? Divide by the average size of the incoming class for cross-university comparison.

How much time do star faculty actually spend in the department? Some professors are on the faculty at multiple universities (Dekel, Phillips) and may spend between two weeks to six months per year at any one place.

General comments

You can ask a question and look stupid, or not ask a question and be stupid.

Take into account that the graduate students who come to the visit day events and talk to admitted students are a biased sample – those who care the most about the department and those who have the most extreme opinions to share.

The field of interest may change during the graduate program, but for most people it does not.

Ask the same question from multiple people and compare answers. This gives an indication of honesty, or at least preparation and coordination of lying.

The PhD comics, especially the earlier ones, are a very accurate description of the lives of graduate students. Note the absence of smileys in this sentence.

The questions admitted graduate students should be asking have been discussed in academia.stackexchange and in urch.com forums.

Automating Facebook conversations

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Facebook makes it easy to remember people’s birthdays, it just displays an automatic reminder. Other calendar programs like Outlook can also be made to do that. Every time someone receives a reminder of an acquaintance’s birthday, they send a birthday greeting – it is almost automatic. So why not make it fully automatic by writing a program to check Facebook every day and send a happy birthday message to anyone whose birthday is on that day?

The person receiving a birthday greeting usually replies with a thank-you note, which is also a repetitive action on a computer and can therefore be automated. Continuing this way, Facebook conversations can be made fully automatic without any human input whatsoever, apart from the initial writing of programs. But Facebook accounts could come with these programs built in, so anyone creating an account will automatically start participating in these computerized conversations. This takes the idea of virtual friendships to its logical limit.

The same virtual conversations can be created using other email and calendar programs – if the calendar displays someone’s birthday, an automatic email is sent with a greeting, and the recipient’s email program sends an automated reply.