Wednesday, June 15, 2005

Good Luck

Good luck can be enticed by accepting opportunity
Men of action are favored by the Goddess of good luck

*) The Richest Man in Babylon

Wednesday, May 25, 2005

The Prisoners' Dilemma

Cooperation is usually analysed in game theory by means of a non-zero-sum game called the "Prisoner's Dilemma" (Axelrod, 1984). The two players in the game can choose between two moves, either "cooperate" or "defect". The idea is that each player gains when both cooperate, but if only one of them cooperates, the other one, who defects, will gain more. If both defect, both lose (or gain very little) but not as much as the "cheated" cooperator whose cooperation is not returned. The whole game situation and its different outcomes can be summarized by table 1, where hypothetical "points" are given as an example of how the differences in result might be quantified.

Action of A\Action of BCooperateDefect
CooperateFairly good [+ 5]Bad [ - 10]
DefectGood [+ 10]Mediocre [0]
Table 1: Outcomes for actor A (in words, and in hypothetical "points") depending on the combination of A's action and B's action, in the "prisoner's dilemma" game situation. A similar scheme applies to the outcomes for B.

The game got its name from the following hypothetical situation: imagine two criminals arrested under the suspicion of having committed a crime together. However, the police does not have sufficient proof in order to have them convicted. The two prisoners are isolated from each other, and the police visit each of them and offer a deal: the one who offers evidence against the other one will be freed. If none of them accepts the offer, they are in fact cooperating against the police, and both of them will get only a small punishment because of lack of proof. They both gain. However, if one of them betrays the other one, by confessing to the police, the defector will gain more, since he is freed; the one who remained silent, on the other hand, will receive the full punishment, since he did not help the police, and there is sufficient proof. If both betray, both will be punished, but less severely than if they had refused to talk. The dilemma resides in the fact that each prisoner has a choice between only two options, but cannot make a good decision without knowing what the other one will do.

Such a distribution of losses and gains seems natural for many situations, since the cooperator whose action is not returned will lose resources to the defector, without either of them being able to collect the additional gain coming from the "synergy" of their cooperation. For simplicity we might consider the Prisoner's dilemma as zero-sum insofar as there is no mutual cooperation: either each gets 0 when both defect, or when one of them cooperates, the defector gets + 10, and the cooperator - 10, in total 0. On the other hand, if both cooperate the resulting synergy creates an additional gain that makes the sum positive: each of them gets 5, in total 10.

The gain for mutual cooperation (5) in the prisoner's dilemma is kept smaller than the gain for one-sided defection (10), so that there would always be a "temptation" to defect. This assumption is not generally valid. For example, it is easy to imagine that two wolves together would be able to kill an animal that is more than twice as large as the largest one each of them might have killed on his own. Even if an altruistic wolf would kill a rabbit and give it to another wolf, and the other wolf would do nothing in return, the selfish wolf would still have less to eat than if he had helped his companion to kill a deer. Yet we will assume that the synergistic effect is smaller than the gains made by defection (i.e. letting someone help you without doing anything in return).

This is realistic if we take into account the fact that the synergy usually only gets its full power after a long term process of mutual cooperation (hunting a deer is a quite time-consuming and complicated business). The prisoner's dilemma is meant to study short term decision-making where the actors do not have any specific expectations about future interactions or collaborations (as is the case in the original situation of the jailed criminals). This is the normal situation during blind-variation-and-selective-retention evolution. Long term cooperations can only evolve after short term ones have been selected: evolution is cumulative, adding small improvements upon small improvements, but without blindly making major jumps.

The problem with the prisoner's dilemma is that if both decision-makers were purely rational, they would never cooperate. Indeed, rational decision-making means that you make the decision which is best for you whatever the other actor chooses. Suppose the other one would defect, then it is rational to defect yourself: you won't gain anything, but if you do not defect you will be stuck with a -10 loss. Suppose the other one would cooperate, then you will gain anyway, but you will gain more if you do not cooperate, so here too the rational choice is to defect. The problem is that if both actors are rational, both will decide to defect, and none of them will gain anything. However, if both would "irrationally" decide to cooperate, both would gain 5 points. This seeming paradox can be formulated more explicitly through the principle of suboptimization.

http://pespmc1.vub.ac.be/PRISDIL.html
http://en.wikipedia.org/wiki/Prisoners_dilemma

Tragedy of the commons

The tragedy of the commons is a metaphor used to illustrate the conflict between individual interests and the common good. The term was popularized by Garrett Hardin in his 1968 Science article "The Tragedy of the Commons."

Hardin uses the example of English Commons, shared plots of grassland used in the past by all livestock farmers in a village. Each farmer keeps adding more livestock to graze on the Commons, because it costs him nothing to do so. In a few years, the soil is depleted by overgrazing, the Commons becomes unusable, and the village perishes.

The cause of any tragedy of the commons is that when individuals use a public good, they do not bear the entire cost of their actions. If each seeks to maximize individual utility, he ignores the costs borne by others. This is an example of an externality. The best (non-cooperative) short-term strategy for an individual is to try to exploit more than his share of public resources. Assuming a majority of individuals follow this strategy, the theory goes, the public resource gets overexploited.

The tragedy of the commons is a source of intense controversy, precisely because it is unclear whether individuals will or will not always follow the overexploitation strategy in any given situation. However, experiments have indicated that individuals do tend to behave in this way

http://en.wikipedia.org/wiki/Tragedy_of_the_commons

Wednesday, December 22, 2004

Mungkin Sekali Saya Sendiri Juga Maling

Oleh Taufiq Ismail

Kita hampir paripurna menjadi bangsa porak-poranda, terbungkuk dibebani hutang dan merayap melata sengsara di dunia. Penganggur 40 juta orang, anak-anak tak bisa bersekolah 11 juta murid, pecandu narkoba 6 juta anak muda, pengungsi perang saudara 1 juta orang, VCD koitus beredar 20 juta keping, kriminalitas merebat di setiap tikungan jalan dan beban hutang
di bahu 1600 trilyun rupiahnya.

Pergelangan tangan dan kaki Indonesia diborgol di ruang tamu Kantor Pegadaian Jagat Raya, dan di punggung kita dicap sablon besar-besar Tahanan IMF dan Penunggak Bank Dunia. Kita sudah jadi bangsa kuli dan babu, menjual tenaga dengan upah paling murah sejagat raya.

Ketika TKW-TKI itu pergi lihatlah mereka bersukacita antri penuh harapan dan angan-angan di pelabuhan dan bandara, ketika pulang lihat mereka berdukacita karena majikan mungkir tidak membayar gaji, banyak yang disiksa malah diperkosa dan pada jam pertama mendarat di negeri sendiri diperas pula.

Negeri kita tidak merdeka lagi, kita sudah jadi negeri jajahan kembali. Selamat datang dalam zaman kolonialisme baru, saudaraku. Dulu penjajah kita satu negara, kini penjajah multi-kolonialis banyak bangsa. Mereka berdasi sutra, ramah-tamah luarbiasa dan banyak senyumnya. Makin banyak kita meminjam uang, makin gembira karena leher kita makin mudah dipatahkannya.

Di negeri kita ini, prospek industri bagus sekali. Berbagai format perindustrian, sangat menjanjikan, begitu laporan penelitian. Nomor satu paling wahid, sangat tinggi dalam evaluasi, dari depannya penuh janji, adalah industri korupsi.

Apalagi di negeri kita lama sudah tidak jelas batas halal dan haram, ibarat membentang benang hitam di hutan kelam jam satu malam.

Bergerak ke kiri ketabrak copet, bergerak ke kanan kesenggol jambret, jalan di depan dikuasai maling, jalan di belakang penuh tukang peras, yang di atas tukang tindas. Untuk bisa bertahan berakal waras saja di Indonesia, sudah untung.

Lihatlah para maling itu kini mencuri secara berjamaah. Mereka bersaf-saf berdiri rapat, teratur berdisiplin dan betapa khusyu’. Begitu rapatnya mereka berdiri susah engkau menembusnya. Begitu sistematiknya prosedurnya tak mungkin engkau menyabotnya. Begitu khusyu’nya, engkau kira mereka beribadah. Kemudian kita bertanya, mungkinkah ada maling
yang istiqamah?

Lihatlah jumlah mereka, berpuluh tahun lamanya, membentang dari depan sampai ke belakang, melimpah dari atas sampai ke bawah, tambah merambah panjang deretan saf jamaah. Jamaah ini lintas agama, lintas suku dan lintas jenis kelamin.

Bagaimana melawan maling yang mencuri secara berjamaah? Bagaimana menangkap maling yang prosedur pencuriannya malah dilindungi dari atas sampai ke bawah? Dan yang melindungi mereka, ternyata, bagian juga dari yang pegang senjata dan yang memerintah.

Bagaimana ini?

Tangan kiri jamaah ini menandatangani disposisi MOU dan MUO (Mark Up Operation), tangan kanannya membuat yayasan beasiswa, asrama yatim piatu dan sekolahan.

Kaki kini jamaah ini mengais-ngais upeti ke sana ke mari, kaki kanannya bersedekah, pergi umrah dan naik haji.

Otak kirinya merancang prosentasi komisi dan pemotongan anggaran, otak kanannya berzakat harta, bertaubat nasuha dan memohon ampunan Tuhan.

Bagaimana caranya melawan maling begini yang mencuri secara berjamaah? Jamaahnya kukuh seperti diding keraton, tak mempan dihantam gempa dan banjir bandang, malahan mereka juru tafsir peraturan dan merancang undang-undang, penegak hukum sekaligus penggoyang hukum, berfungsi bergantian.

Bagaimana caranya memroses hukum maling-maling yang jumlahnya ratusan ribu, barangkali sekitar satu juta orang ini, cukup jadi sebuah negara mini, meliputi mereka yang pegang kendali perintah, eksekutif, legislatif, yudikatif dan dunia bisnis, yang pegang pestol dan mengendalikan meriam, yang berjas dan berdasi. Bagaimana caranya?

Mau diperiksa dan diusut secara hukum?
Mau didudukkan di kursi tertuduh sidang pengadilan?
Mau didatangkan saksi-saksi yang bebas dari ancaman?
Hakim dan jaksa yang bersih dari penyuapan?

Percuma

Seratus tahun pengadilan, setiap hari 8 jam dijadwalkan Insya Allah tak akan terselesaikan.

Jadi, saudaraku, bagaimana caranya? Bagaimana caranya supaya mereka mau dibujuk, dibujuk, dibujuk agar bersedia mengembalikan jarahan yang berpuluh tahun dan turun-temurun sudah mereka kumpulkan. Kita doakan Allah membuka hati mereka, terutama karena terbanyak dari mereka orang yang shalat juga, orang yang berpuasa juga, orang yang berhaji juga.
Kita bujuk baik-baik dan kita doakan mereka.

Celakanya, jika di antara jamaah maling itu ada keluarga kita, ada hubungan darah atau teman sekolah, maka kita cenderung tutup mata, tak sampai hati menegurnya.

Celakanya, bila di antara jamaah maling itu ada orang partai kita, orang seagama atau sedaerah, kita cenderung menutup-nutupi fakta, lalu dimakruh-makruhkan dan diam-diam berharap semoga kita mendapatkan cipratan harta tanpa ketahuan.

Maling-maling ini adalah kawanan anai-anai dan rayap sejati. Dan lihat kini jendela dan pintu rumah Indonesia dimakan rayap. Kayu kosen, tiang, kasau, jeriau rumah Indonesia dimakan anai-anai. Dinding dan langit- langit, lantai rumah Indonesia digerogoti rayap. Tempat tidur dan
lemari, meja kursi dan sofa, televisi rumah Indonesia dijarah anai-anai.
Pagar pekarangan, bahkan fondasi dan atap rumah Indonesia sudah mulai habis dikunyah-kunyah rayap. Rumah Indonesia menunggu waktu, masa rubuhnya yang sempurna.

Aku berdiri di pekarangan, terpana menyaksikannya.
Tiba-tiba datang serombongan anak muda dari kampung sekitar.
“Ini dia rayapnya! Ini dia Anai-anainya!” teriak mereka.
“Bukan. Saya bukan Rayap, bukan!” bantahku.

Mereka berteriak terus dan mendekatiku dengan sikap mengancam.
Aku melarikan diri kencang-kencang.
Mereka mengejarkan lebih kenjang lagi.
Mereka menangkapku.
“Ambil bensin!” teriak seseorang.
“Bakar Rayap,” teriak mereka bersama.
Bensin berserakan dituangkan ke kepala dan badanku.
Seseorang memantik korek API.
Aku dibakar.
Bau kawanan rayap hangus.
Membubung Ke udara.

Monday, November 22, 2004

Taba Naba

Taba naba naba norem
Tugi penai siri
Dinghy e naba we
Miko keimi
Sere re naba we
Taba naba norem

Thursday, October 28, 2004

Understanding experience*

Most internet stores allow you to buy things, but do you go shopping? Shopping is as much about going to the shop, feeling the clothes, being with friends. You can go shopping and never intend to spend money. Shopping is not about an efficient financial transaction, it is an experience.
But experience is a difficult thing to pin down; we understand the idea of good experience, but how do we define it and even more difficult how we design it?

*) cited from Dix's HCI book

Friday, October 22, 2004

Guns, Germs, and Steel*

History followed different courses for different peoples because of differences among peoples' environments, not because of biological differences among peoples themselves

*) a book of Jared Diamond

Thursday, October 14, 2004

will ontology help?

Simple ontologies (taxonomies) provide: *

  • Controlled shared vocabulary (search engines, authors, users, databases, programs/agents all speak same language)
  • Site Organization, Navigation Support, Expectation setting
  • “Umbrella” Upper Level Structures (for extension e.g., UNSPSC)
  • Browsing support (tagged structures such as Yahoo!)
  • Search support (query expansion approaches such as FindUR, e-Cyc)
  • Sense disambiguation (e.g., TAP)
and for more structured ontologies may be used in:
  • Consistency checking
  • Completion
  • Interoperability support
  • Support for validation and verification testing configuration support
  • Structured, “surgical” comparative customized search
  • Generalization/ Specialization
  • Foundation for expansion and leverage

    *) cited from McGuinness' paper