Feature Selection for Linear SVM with Provable Guarantees

We give two provably accurate feature-selection techniques for the linear SVM. The algorithms run in deterministic and randomized time respectively. Our algorithms can be used in an unsupervised or supervised setting. The supervised approach is based on sampling features from support vectors. We prove that the margin in the feature space is preserved to within $\epsilon$-relative error of the margin in the full feature space in the worst-case. In the unsupervised setting, we also provide worst-case guarantees of the radius of the minimum enclosing ball, thereby ensuring comparable generalization as in the full feature space and resolving an open problem posed in Dasgupta et al. We present extensive experiments on real-world datasets to support our theory and to demonstrate that our method is competitive and often better than prior state-of-the-art, for which there are no known provable guarantees.Comment: Appearing in Proceedings of 18th AISTATS, JMLR W&CP, vol 38, 201

Rehabilitating agriculture and promoting food security following the 2010 Pakistan floods: Insights from South Asian experience

The recent floods in Pakistan have had a devastating effect on the Pakistani population. The Office for the Coordination of Humanitarian Affairs (OCHA 2010) estimates that, as of early September 2010, more than 20 million people had been displaced by the flood and by some estimates the damage to crops, housing, other buildings, roads, and irrigation infrastructure now reaches $6.5 billion (OCHA 2010).* Recovery experiences from previous natural disasters in Pakistan and throughout South Asia, especially the 2005 earthquake in Pakistan and the 1998 flood in Bangladesh, suggest lessons in four broad areas that are relevant for recovery efforts following the 2010 Pakistan flood. First, market and trade policies should be clear, transparent, and consistent, maintaining adequate price incentives so that private trade and imports can contribute to postdisaster recovery. Restoration of private trade (and even promotion of expansion of trade) can enhance both price stability and food security more effectively and at far less cost than otherwise, particularly in the rehabilitation phase. Recovery experiences from previous natural disasters in Pakistan and throughout South Asia, especially the 2005 earthquake in Pakistan and the 1998 flood in Bangladesh, suggest lessons in four broad areas that are relevant for recovery efforts following the 2010 Pakistan flood. Second, there is a need for a strong institutional framework to coordinate the large-scale disaster response. Long-term and short-term goals need to be accounted for and integrated into a comprehensive postdisaster response framework. Involvement of all affected stakeholders in the policy formulation is important to ensure representation and participation. Third, recovery efforts should also include support for livelihood security and restoration and ensure inclusion of the stakeholders. In the immediate aftermath of the floods, a provision of compensation based on loss of livelihoods might be necessary to assist affected groups. Alternative strategies for the poor to cope with the loss of income need to be examined (including credit provision) so as to avoid high and unsustainable household indebtedness. Fourth, evaluation of previously implemented projects suggests that focus on not only restoring infrastructure facilities but also upgrading them can lead to enhanced flood resistance as well as a reduction in future disaster loss. In addition, the resumption of normal agricultural activities as soon as possible is vital for the country's recovery. The provision of inputs to affected smallholders is necessary for the resumption of normal livelihood activities. The 2010 Pakistan National Disaster Response Plan incorporates some of these lessons learned from earlier disasters. However, despite the establishment of national and sub-national disaster management authorities, significant challenges to the functioning of this system still remain. Two alternative institutions present themselves as possible vehicles for the delivery of poverty-alleviating interventions and resources—the Pakistan Poverty Alleviation Fund (PPAF) and the Benazir Income Support Programme (BISP). PPAF uses a participatory and community-based model and comprises a network of more than 130,000 community organizations and groups in 127 districts covering 30,000 villages. This large and established network puts PPAF in a convenient position to reach affected communities in a timely and efficient manner. BISP has a partnership with the National Database and Registration Authority (NADRA) that is being used to provide necessary financial support to flood victims throughout the country. However, there are several obstacles to the successful disbursement of funds through BISP. In particular, because a large percentage of displaced people do not possess computerized national identity cards, these people could be excluded from the income support programs unless a new comprehensive listing is done. Finally, it is important to establish and strengthen disaster response capability so that the country can better respond to recurring natural disasters. Emergency early warning system mechanisms have the potential to substantially reduce casualties and economic losses from disasters, and they need to be strengthened. Likewise, the lessons learned from the relief and rehabilitation response to the 2010 floods should be incorporated in contingency plans for future natural disasters.floods, lessons learned, postdisaster recovery and rehabilitation,

A Survey of the History of the Death Penalty in the United States

Since the founding of Jamestown Colony in 1607, few topics in American life and culture have generated as much controversy, both in terms of persistence and volatility, as the death penalty. Foreign policy, economic recessions, and social movements come to the forefront of national discussion in their own respective ebbs and flows. Capital punishment, however, has been a staple of the American criminal justice system since the early inhabiting of the continent, and has remained a permanent vehicle through which we can enact retribution on the most heinous criminal offenders in our society, ridding ourselves of the worst among us

Evolutionary models of cold and low-mass planets: Cooling curves, magnitudes, and detectability

Future instruments like NIRCam and MIRI on JWST or METIS at the ELT will be able to image exoplanets that are too faint for current direct imaging instruments. Evolutionary models predicting the planetary intrinsic luminosity as a function of time have traditionally concentrated on gas-dominated giant planets. We extend these cooling curves to Saturnian and Neptunian planets. We simulate the cooling of isolated core-dominated and gas giant planets with masses of 5 Earthmasses to 2 Jupitermasses. The luminosity includes the contribution from the cooling and contraction of the core and of the H/He envelope, as well as radiogenic decay. For the atmosphere we use grey, AMES-Cond, petitCODE, and HELIOS models. We consider solar and non-solar metallicities as well as cloud-free and cloudy atmospheres. The most important initial conditions, namely the core-to-envelope ratio and the initial luminosity are taken from planet formation simulations based on the core accretion paradigm. We first compare our cooling curves for Uranus, Neptune, Jupiter, Saturn, GJ 436b, and a 5 Earthmass-planet with a 1% H/He envelope with other evolutionary models. We then present the temporal evolution of planets with masses between 5 Earthmasses and 2 Jupitermasses in terms of their luminosity, effective temperature, radius, and entropy. We discuss the impact of different post formation entropies. For the different atmosphere types and initial conditions magnitudes in various filter bands between 0.9 and 30 micrometer wavelength are provided. Using black body fluxes and non-grey spectra, we estimate the detectability of such planets with JWST. It is found that a 20 (100) Earthmass-planet can be detected with JWST in the background limit up to an age of about 10 (100) Myr with NIRCam and MIRI, respectively.Comment: Language corrected version and improved arrangements of figures, online data at: http://www.space.unibe.ch/research/research_groups/planets_in_time/numerical_data/index_eng.htm

Rehabilitating Agriculture and Promoting Food Security After the 2010 Pakistan Floods: Insights from the South Asian Experience

The 2010 floods in Pakistan had a devastating effect on the Pakistani population. This paper summarises recovery experiences from previous natural disasters in South Asia, including the 2005 earthquake in Pakistan and the 1998 flood in Bangladesh, and suggests several lessons relevant for recovery efforts following the 2010 Pakistan flood. First, market and trade policies should maintain adequate price incentives so that private trade and imports can contribute to postdisaster recovery. Second, a strong institutional framework is needed to coordinate the large-scale disaster response. Third, recovery efforts should also include support for livelihood security and restoration, ensuring inclusion of the stakeholders. Fourth, restoring and upgrading infrastructure facilities can lead to enhanced flood resistance as well as a reduction in future disaster loss. Two alternative institutions may be possible vehicles for poverty-alleviation—the Pakistan Poverty Alleviation Fund (PPAF) and the Benazir Income Support Programme (BISP). To address future disasters, however, it is important to establish and strengthen disaster response capability, including applying lessons learned from the relief and rehabilitation response to the 2010 floods