16,447 research outputs found
Quilting Stochastic Kronecker Product Graphs to Generate Multiplicative Attribute Graphs
We describe the first sub-quadratic sampling algorithm for the Multiplicative
Attribute Graph Model (MAGM) of Kim and Leskovec (2010). We exploit the close
connection between MAGM and the Kronecker Product Graph Model (KPGM) of
Leskovec et al. (2010), and show that to sample a graph from a MAGM it suffices
to sample small number of KPGM graphs and \emph{quilt} them together. Under a
restricted set of technical conditions our algorithm runs in time, where is the number of nodes and is the number of edges
in the sampled graph. We demonstrate the scalability of our algorithm via
extensive empirical evaluation; we can sample a MAGM graph with 8 million nodes
and 20 billion edges in under 6 hours
Model-Independent Measurement of the Primordial Power Spectrum
In inflationary models with minimal amount of gravity waves, the primordial
power spectrum of density fluctuations, , together with the basic
cosmological parameters, completely specify the predictions for the cosmic
microwave background (CMB) anisotropy and large scale structure. Here we show
how we can strongly constrain both and the cosmological parameters
by combining the data from the Microwave Anisotropy Probe (MAP) and the galaxy
redshift survey from the Sloan Digital Sky Survey (SDSS). We allow
to be a free function, and thus probe features in the primordial power spectrum
on all scales. MAP and SDSS have scale-dependent measurement errors that
decrease in opposite directions on astrophysically interesting scales; they
complement each other and allow the measurement of the primordial power
spectrum independent of inflationary models, giving us valuable information on
physics in the early Universe, and providing clues to the correct inflationary
model.Comment: 4 pages including 4 figures. To appear in "Particle Physics and the
Early Universe (COSMO-98)", editor David O. Caldwell (American Institute of
Physics
A Note on Poverty in Kosovo
Kosovo is a war-torn corner of the former Yugoslavia, where a civil war between ethnic Albanians and ethnic Serbs raged during most of the 1990s. We examine the incidence and depth of poverty and some of its correlates in post-conflict Kosovo using the Living Standards Measurement Survey.http://deepblue.lib.umich.edu/bitstream/2027.42/40193/3/wp807.pd
Distributed Stochastic Optimization of the Regularized Risk
Many machine learning algorithms minimize a regularized risk, and stochastic
optimization is widely used for this task. When working with massive data, it
is desirable to perform stochastic optimization in parallel. Unfortunately,
many existing stochastic optimization algorithms cannot be parallelized
efficiently. In this paper we show that one can rewrite the regularized risk
minimization problem as an equivalent saddle-point problem, and propose an
efficient distributed stochastic optimization (DSO) algorithm. We prove the
algorithm's rate of convergence; remarkably, our analysis shows that the
algorithm scales almost linearly with the number of processors. We also verify
with empirical evaluations that the proposed algorithm is competitive with
other parallel, general purpose stochastic and batch optimization algorithms
for regularized risk minimization
Was the Mandal Commission Right? Living Standard Differences between Backward Classes and Other Social Groups in India
Affirmative action has been at the heart of public policies towards the socially disadvantaged in India. Compensatory discrimination policies which have been adopted for the Scheduled Castes (SC) and Scheduled Tribes (ST) since independence were recommended for Other Backward Classes (OBC) by the Mandal Commission established by the Indian government in 1979. We examine why OBC have lower living standards, as measured by per capita household consumption expenditures, relative to the mainstream population, and whether these reasons are similar to those observed for SC and ST. We find that while the causes of the living standard gap for the OBC are broadly similar to those for the SC and ST, the role of educational attainment in explaining the gap is higher in importance for the OBC.living standards, caste, reservation policy, decomposition
Was the Mandal Commission Right? Living Standard Differences between Backward Classes and Other Social Groups in India
Affirmative action has been at the heart of public policies towards the socially disadvantaged in India. Compensatory discrimination policies which have been adopted for the Scheduled Castes (SC) and Scheduled Tribes (ST) since independence were recommended for Other Backward Classes (OBC) by the Mandal Commission established by the Indian government in 1979. We examine why OBC have lower living standards, as measured by per capita household consumption expenditures, relative to the mainstream population, and whether these reasons are similar to those observed for SC and ST. We find that while the causes of the living standard gap for the OBC are broadly similar to those for the SC and ST, the role of educational attainment in explaining the gap is higher in imporatnce for the OBC.
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