Pandora's Box Problem with Order Constraints

The Pandora's Box Problem, originally formalized by Weitzman in 1979, models selection from set of random, alternative options, when evaluation is costly. This includes, for example, the problem of hiring a skilled worker, where only one hire can be made, but the evaluation of each candidate is an expensive procedure. Weitzman showed that the Pandora's Box Problem admits an elegant, simple solution, where the options are considered in decreasing order of reservation value,i.e., the value that reduces to zero the expected marginal gain for opening the box. We study for the first time this problem when order - or precedence - constraints are imposed between the boxes. We show that, despite the difficulty of defining reservation values for the boxes which take into account both in-depth and in-breath exploration of the various options, greedy optimal strategies exist and can be efficiently computed for tree-like order constraints. We also prove that finding approximately optimal adaptive search strategies is NP-hard when certain matroid constraints are used to further restrict the set of boxes which may be opened, or when the order constraints are given as reachability constraints on a DAG. We complement the above result by giving approximate adaptive search strategies based on a connection between optimal adaptive strategies and non-adaptive strategies with bounded adaptivity gap for a carefully relaxed version of the problem

Terrorism and Universal Jurisdiction: Opening a Pandora\u27s Box?

The relationship between terrorism and international criminal law has provoked a good deal of discussion in the wake of the terrorist attacks of September 11, 2001 in New York City and at the Pentagon in Washington, D.C. A particularly challenging issue pertains to whether terrorism is an international crime or a transnational crime, and if and in what context offenders and offenses, to which we affix the label of terrorist and terrorism, should or can be subject to the limited jurisdiction of the International Criminal Court (ICC) and other international and national criminal tribunals

Terrorism and Universal Jurisdiction: Opening a Pandora\u27s Box?

The relationship between terrorism and international criminal law has provoked a good deal of discussion in the wake of the terrorist attacks of September 11, 2001 in New York City and at the Pentagon in Washington, D.C. A particularly challenging issue pertains to whether terrorism is an international crime or a transnational crime, and if and in what context offenders and offenses, to which we affix the label of terrorist and terrorism, should or can be subject to the limited jurisdiction of the International Criminal Court (ICC) and other international and national criminal tribunals

The perception of three-dimensionality across continuous surfaces

The apparent three-dimensionality of a viewed surface presumably corresponds to several internal preceptual quantities, such as surface curvature, local surface orientation, and depth. These quantities are mathematically related for points within the silhouette bounds of a smooth, continuous surface. For instance, surface curvature is related to the rate of change of local surface orientation, and surface orientation is related to the local gradient of distance. It is not clear to what extent these 3D quantities are determined directly from image information rather than indirectly from mathematically related forms, by differentiation or by integration within boundary constraints. An open empirical question, for example, is to what extent surface curvature is perceived directly, and to what extent it is quantitative rather than qualitative. In addition to surface orientation and curvature, one derives an impression of depth, i.e., variations in apparent egocentric distance. A static orthographic image is essentially devoid of depth information, and any quantitative depth impression must be inferred from surface orientation and other sources. Such conversion of orientation to depth does appear to occur, and even to prevail over stereoscopic depth information under some circumstances

Pandora\u27s Box: The Liberation of Welfare Mothers

Excerpt from the full-text article: The non- misandrist mainstream of the women\u27s movement has suggested that, more than women being liberated from male oppression, both sexes need to be liberated from the tyranny of culturally determined sex roles, the last bastion of ascribed status. If all social roles were androgynous they could be based on more relevant criteria. For example, children would be encouraged to develop skills and talents without regard for their appropriateness to gender, the male-female ratio in the work force and in nearly all specific occupations would be virtually equal, pay would be equal, and the number of female breadwinners would not only equal male breadwinners, but the number of housewives would not greatly exceed the number of househusbands. It is the contention of this paper that there is no group of women in America more desperately in need of such a sex role revolution than welfare mothers and none less likely to share in one. This is drawn from a review of the literature in answer to these questions: Who are the welfare mothers? How would a sex role revolution affect welfare? Why are welfare mothers especially in need of liberation from sex roles? And what are the factors militating against such liberation