2008년 6월 27일 금요일

Amartya Sen, "Poverty: An Ordinal Approach to Measurement", Econometrica, Vol. 44, No. 2 (Mar., 1976), pp. 219-231

The primary aim of this paper is to propose a new measure of poverty, which should avoid some of the shortcomings of the measures currently in use. An axiomatic approach is used to derive the measure. The conception of welfare in the axiom set is ordinal. The information requirement for the new measure is quite limited, permitting practical use.

WALTER BOSSERT, CONCHITA D'AMBROSIO, VITO PERAGINE (2007) Deprivation and Social Exclusion

Social exclusion manifests itself in the persistent relative lack of an individual's access to functionings compared with other members of society, and we model it as being in a state of deprivation over time. We view deprivation as having two basic determinants: the lack of identification with other members of society, and the aggregate alienation experienced by an agent with respect to those having fewer functioning failures. Using an axiomatic approach, we characterize new individual and aggregate measures of deprivation and social exclusion. The aggregate measures are then applied to EU data for the period 1994–2001.

Walter Bossert and Conchita D'Ambrosio (2007) "Dynamic Measures of Individual Deprivation", Social Choice and Welfare Vol.28: 77-88

We introduce a one-parameter class of individual deprivation measures. Motivated by a suggestion of Runciman, we modify Yitzhaki’s index by multiplying it by a function that is interpreted as measuring the part of deprivation generated by an agent’s observation that others in his reference group move on to a higher level of income than himself. The parameter reflects the relative weight given to these dynamic considerations, and the standard Yitzhaki index is obtained as a special case. In addition, we characterize more general classes of measures that pay attention to this important dynamic aspect of deprivation.

Satya R. Chakravarty, Conchita D'Ambrosio (2006) THE MEASUREMENT OF SOCIAL EXCLUSION

This paper develops an axiomatic approach to the measurement of social exclusion. At the individual level, social exclusion is viewed in terms of deprivation of the person concerned with respect to different functionings in the society. At the aggregate level we treat social exclusion as a function of individual exclusions. The class of subgroup decomposable social exclusion measures using a set of independent axioms is identified. We then look at the problem of ranking exclusion profiles by the exclusion dominance principle under certain restrictions. Finally, applications of decomposable and non-decomposable measures suggested in the paper using European Union and Italian data are also considered.

2008년 6월 22일 일요일

Memos after 2008 SSCW Meeting

The two-stage rules for multi-issue allocation situations

Silvia María Lorenzo Freire Universidade da Coruña, slorenzo@udc.es
Gustavo Bergantiños Universidade de Vigo, gbergant@uvigo.es
Leticia Lorenzo Universidade de Vigo, leticiap@uvigo.es

In a bankruptcy problem, there is an estate to be divided among a number of claimants, whose total claim exceeds the estate available. The multi-issue allocation situations are used to model bankruptcy-like problems in which the estate is divided not on the basis of a single claim for each agent, but several claims resulting from so-called issues. We consider extensions of well-known bankruptcy rules such as the proportional rule, the constrained equal awards rule, and the constrained equal losses rule. These extensions are obtained by means of a procedure in two stages where first the estate is divided among the issues and then the quantity obtained for each issue is divided among the agents. We study these rules from an axiomatic point of view. In this way, we introduce suitable properties in this context and characterize some of the two-stage rules with them. Although these extensions have been studied previously (see Lorenzo-Freire et al. (2005), for example), we pursue a more ambitious program, surveying it from most of the perspectives that have found to be fruitful in previous literature on standard bankruptcy problems.

  • This paper related with my paper with Eiichi and Toyo. They may need our paper since they are not aware of it.
Limited rights and social choice rules

Maurice Salles Universite de Caen, maurice.salles@unicaen.fr

In 1970 Sen introduced within social choice theory the notion of minimal liberty and proved an impossibility result concerning social decision functions. In the present paper, Sen''s condition of (minimal) liberty is weakened within the framework of social choice rules. It is then shown that the same kind of impossibility obtains for social choice functions.

  • With his weakening of Sen's minimal liberalism, extended Pareto rule satisfies all axioms imposed in Sen's theorem. But is there other rules? Isn't the Pareto rule the only rule satisfying them? I asked this question and the author seems does not know the answer.


Implementation via code of rights

Semih Koray Bilkent University, ksemih@bilkent.edu.tr
Kemal Yildiz Bilkent University, kemaly@bilkent.edu.tr

Implementation of a social choice rule can be thought of as a design of power(re)distribution in the society such that the society''s "equilibrium outcomes" coincide with the alternatives chosen by the social choice rule at any preference profile of the society. In this paper, we introduce a new societal framework for implementation which takes the power distribution in the society, represented by a code of rights, as its point of departure. We examine and identify how implementation via code of rights (referred to as gamma implementation) is related to classical Nash implementation via a mechanism. We characterize gamma implementability when the state space on which the rights structure is to be specified consists of the alternatives from which a social choice is to be made. We show that a social choice rule is gamma implementable if it satisfies pivotal oligarchic monotonicity - a notion introduced in this study. Moreover, pivotal oligarchic monotonicity conjoined with Pareto optimality turns out to be sufficient for a non-empty valued social choice rule to be gamma implementable. Finally we revisit "liberal''s paradox" of A.K. Sen, which turns out to fit very well into the gamma implementation framework.
  • Seems related with my paper on individual powers and social consent.

Arthur C. Clarke, 2001: A Space Odyssey (1968)

2001: A Space Odyssey (1968) is a science fiction novel by Arthur C. Clarke. It was developed concurrently with Stanley Kubrick's film version and published after the release of the film. The story is based in part on various short stories by Clarke, most notably "The Sentinel" (written in 1948 for a BBC competition but first published in 1951 under the title "Sentinel of Eternity"). For an elaboration of Clark and Kubrick's collaborative work on this project, see The Lost Worlds of 2001, Arthur C. Clarke, Signet., 1972.
The first part of the novel (in which aliens nudge the primitive human ancestors) is similar to the plot of an earlier Clarke story, "Encounter at Dawn".
Aliens keeping a watch on development of intelligent beings everywhere and helping where they can is an idea this novel shares with "Rescue Party", Clarke's first published story.
The opening of another Clarke story, "Transience", is set in the same period of human history as the first part of this novel; but the two stories are unrelated.

Plot summary

In the background to the story in the book, an ancient and unseen alien race uses a mechanism with the appearance of a large crystal Monolith to investigate worlds all across the galaxy and, if possible, to encourage the development of intelligent life. The book shows one such monolith appearing in ancient Africa, three million years B.C., where it inspires a starving group of the hominid ancestors of human beings to conceive of tools. The ape-men use their tools to kill animals and eat meat, ending their starvation. They then use the tools to kill a leopard that had been preying on them; the next day, the main ape character, Moon-Watcher, uses a club to kill the leader of a rival tribe. Moon-Watcher reflects that he is now master of the universe, but is unsure of what to do—but he'll think of something. The book suggests that the monolith was instrumental in awakening intelligence, and enabling the transition of the ape-men to a higher order, with the ability to fashion crude tools and thereby be able to hunt and forage for food in much more efficient fashion.
The book then leaps eons to the year 2001, detailing Dr. Heywood Floyd's travel to Clavius Base on the Moon. Upon his arrival, Floyd attends a meeting. A lead scientist explains that they have found a magnetic disturbance in Tycho, one of the Moon's craters, designated Tycho Magnetic Anomaly-One (TMA-1). An excavation of the area has revealed a large black slab; it is precisely fashioned to a ratio of exactly 1:4:9, or 1²:2²:3² (that is to say the thickness of the slab is exactly 1/4th the width and 1/9th the height). Such a construction rules out any naturally-occurring phenomena, and at three million years of age, it was not crafted by human hands. It is the first evidence for the existence of extraterrestrial intelligent life. Floyd and a team of scientists drive across the moon to actually view TMA-1. They arrive just as sunlight hits upon it for the first time in three million years. It then sends a piercing radio transmission to the far reaches of the solar system.
The book then leaps forward 18 months to the Discovery One mission to Saturn. David Bowman and Frank Poole are the only conscious human beings aboard Discovery One spaceship. Three of their colleagues are in a state of suspended animation, to be awakened when they near Saturn. The HAL 9000, an artificially intelligent computer, maintains the ship and is a vital part of life aboard.
While Poole is receiving a birthday message from his family back home, HAL tells him that the AE-35 unit of the ship is going to malfunction. Poole takes one of the extra-vehicular pods and swaps the AE-35 unit, which is critical for sustaining communication with Earth. Bowman conducts tests on the AE-35 unit that has been replaced and determines that there was never anything wrong with it. Later, HAL claims that the replacement AE-35 unit will fail. Apprehensive, Poole and Bowman radio back to Earth; they are told that something is wrong with HAL and are given orders to disconnect him. These instructions are interrupted as the signal is broken. HAL informs them that the AE-35 unit has malfunctioned.
Poole takes a pod outside the ship to bring in the failed AE-35 unit. As he is removing the unit, the pod, which he had left further from the ship, begins moving toward him. He is powerless to move out of the way in time and is killed by the impact; his spacesuit is ripped open. Bowman is shocked by Poole's death and is deeply distressed. He is unsure whether HAL, a computer, really could have killed Poole. He decides that he will need to wake up the other three astronauts. He has a long argument with HAL, with HAL refusing to obey his orders, insisting that Bowman is incapacitated. Bowman threatens to disconnect him if his orders are not obeyed, and HAL relents, giving him manual control to wake the sleeping scientists.
As Bowman begins to awaken his colleagues, he feels a cold chill; HAL has opened the inner and outer airlock doors to space, venting the ship’s atmosphere. The pressure on board is rapidly dropping as the ship is equalizing with the vacuum of space. Bowman makes his way into a sealed emergency shelter which has an isolated oxygen supply and spare spacesuit. He then puts on the spacesuit and re-enters the ship, knowing that HAL has killed the three hibernating astronauts. Bowman then laboriously disconnects the computer, puts the ship back in order and manually re-establishes contact with Earth. He then learns that the true purpose of the mission is to explore Japetus (the third-largest moon of Saturn), in the hope of contacting the society that buried the monolith on the Moon.
Bowman learns that HAL had begun to feel guilty and conflicted about keeping the purpose of the mission from him and Poole, which ran contrary to his stated mission of gathering information and reporting it fully. This conflict had started to manifest itself in little errors. Given time, HAL might have been able to resolve this crisis peacefully, but when he was threatened with disconnection, he defended himself, believing his very existence to be at stake.
Bowman spends months on the ship, alone, slowly approaching Japetus. A return to Earth is out of the question, as HAL's sudden decompression of Discovery severely damaged the ship's air filtration system, leaving Bowman with far less breathable air than either returning to Earth or waiting for a rescue ship would require. Hibernation is impossible without HAL to monitor it. During his long approach, he gradually notices a small black spot on the surface of Japetus. When he gets closer, he realizes that this is an immense black monolith, identical to TMA-1, only much larger, which the scientists back on Earth name "TMA-2", which is a misnomer because it gives off no magnetic force whatsoever.
He decides to go out in one of the extra-vehicular pods and investigate the monolith. Inert for aeons, the monolith reveals its true purpose as a stargate when it opens and pulls in Bowman's pod. Before he vanishes, Mission control hears him proclaim: "The thing's hollow — it goes on forever — and — oh my God! — It's full of stars!"
Bowman is transported via the monolith to a star system far outside our galaxy. During this journey, he goes through a large interstellar switching station, and sees other species' spaceships going on other routes, calling it in likeness to the 'Grand Central Station' of the universe. (This is rather different from the film, which portrayed the entire journey as surreal.)
He is brought to what appears to be a nice hotel suite, carefully constructed from monitored television transmissions, to make him feel at ease. Bowman goes to sleep. As he sleeps, his mind and memories are drained from his body. David Bowman is made into a new immortal entity that can live and travel in space; a Star Child. The Star Child then returns to our Solar System and to Earth. After slightly testing his newfound powers by setting off what can be assumed, several megatons of nuclear energy, Bowman reflects that he is now master of his universe, but is uncertain of what to do—but hopefully he'll think of something.