1,099 research outputs found
United States v. Maynard and Enforcement of United States Drug Trafficking Laws on the High Seas: How Far Does United States Jurisdiction Really Reach?
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Three Essays on Development and the Political Economy of South Asia
This dissertation consists of three essays on various aspects of development and the political economy of developing countries. The first two chapters share a focus on issues of political economy in South Asia, the first examining the influence of politics over public goods allocations, and the second the effects of ethno-religious politics on voter behavior, violence, and policy outcomes. The third chapter shares with the first two its geographic setting, being located in South Asia, but focuses on education, employing an RCT design to evaluate the efficacy of public-private partnerships in delivering high-quality primary education to remote communities. The first chapter examines the role of political parties in India's national government in shaping public goods allocations. Party preference is often regarded as important for shaping policy outcomes, but the empirical literature has yielded mixed results, with some research finding substantial party effects, and other research little to none. The discrepancies in estimated party effects are likely due to a combination of heterogeneous party characteristics and institutional context, as well as the the nature of political competition itself, with parties facing a trade-off in the promotion of their most preferred policies against the electoral incentive to cater to the median voter. To generate random random variation in party identity, I make use of the assassination of the Congress party leader, Rajiv Gandhi, in the midst of India's 1991 national elections, which had the effect of dramatically increasing the probability of Congress victory for a subset of constituencies. Using this variation, I find that representation by the ruling Congress party leads to a substantial increase in the provision of public goods favored by the poor, consistent with the party's expressed populist agenda. Among the salient changes are increases in the availability of drinking water and declines in infrastructure such as productive electrification and paved roads. I also estimate party effects using a regression discontinuity identification strategy, which generates variation in party identity for closely contested elections. Here I find little effect of Congress representation on public goods allocations. I argue that the reason for the differences between the results estimated with the two identification strategies is the importance of both the identity of the winning party, as well as the margin of victory. The second chapter examines the role of ethno-religious propaganda in generating support for political parties espousing ideologies of ethno-religious nationalism. A significant literature has shown the effects of political campaigns and media bias in influencing voter behavior. Ethnic identity often figures prominently in campaigns of voter mobilization, particularly in developing countries, where ethnic identities tend to be more salient, and state resources more subject to capture through power over the state. A large body of research has shown the ways in which, not only does ethnic diversity create an environment conducive to the ethnicization of political competition, but political competition itself contributes to the increased salience of ethnic identity.Prior to India's 1991 national elections, the leader of the Hindu-nationalist BJP political party toured northern India on a "pilgrimage" to the city of Ayodhya, holding numerous rallies along the way to promote the construction of a Hindu temple there. Causal identification of the campaign's effects comes through the incidental exposure of localities due to their lying along the road joining the cities which were the ultimate destinations of the campaign. The main result is that the campaign increased the BJP's vote share by 5-9 percentage points in visited constituencies, which translated to a 10-20 percentage points increase in the probability of victory. I also find that the campaign significantly increased the probability of riots, which were 9 percentage points more likely to occur in constituencies through which the campaign passed; and that the riots associated with the campaign increased the party's vote share by 3.5 percentage points. There is also evidence that the campaign increased the availability of local public goods, with the sub-district through which the campaign directly passed showing a 3-6 percentage points increase in a variety of public goods, such as electrification, drinking water, and primary schools. The third chapter, which is jointly authored with Leigh Linden, Felipe Barrera-Osorio, Dhushyanth Raju, and Matthew Hoover, examines the efficacy of public-private partnerships for delivering high-quality primary education to remote, and underserved, communities. Private entrepreneurs were enlisted to establish and operate primary schools throughout rural Sindh province in Pakistan, for which they were paid a per-child subsidy, with all local children between the ages of 5 and 9 allowed tuition-free enrollment. To address potential sources of endogeneity, the intervention was designed as a randomized control trial (RCT): 263 villages were identified as qualifying for the program, of which 200 were randomly assigned a school. In addition, half of the treatment villages were assigned a subsidy scheme whereby entrepreneurs were paid slightly more for girls than boys. The program proved remarkably effective, with enrollment increasing by 30-50 percentage points. Child test scores also improved considerably, with children in treatment villages scoring 0.67 standard deviations higher on administered exams. Interestingly, there was no differential effect on female enrollment for either subsidy scheme, which we attribute to the lack of a pre-existing gender gap in enrollment
The Inner Halo of M87: A First Direct View of the Red-Giant Population
An unusually deep (V,I) imaging dataset for the Virgo supergiant M87 with the
Hubble Space Telescope ACS successfully resolves its brightest red-giant stars,
reaching M_I(lim) = -2.5. After assessing the photometric completeness and
biasses, we use this material to estimate the metallicity distribution for the
inner halo of M87, finding that the distribution is very broad and likely to
peak near [m/H] ~ -0.4 and perhaps higher. The shape of the MDF strongly
resembles that of the inner halo for the nearby giant E galaxy NGC 5128. As a
byproduct of our study, we also obtain a preliminary measurement of the
distance to M87 with the TRGB (red-giant branch tip) method; the result is
(m-M)_0 = 31.12 +- 0.14 (d = 16.7 +- 0.9 Mpc). Averaging this result with three
other recent techniques give a weighted mean d(M87) = (16.4 +- 0.5) Mpc.Comment: In press for Astronomy and Astrophysic
Global Patterns of Lightning Properties Derived by LIS
The Lightning Imaging Sensor LIS aboard the TRMM satellite provides unmatched empirical data of the global lightning distribution (up to approx.35deg S/N) since end of 1997. Climatological flash rate densities derived from LIS are standard references, e.g. for flash rate parameterizations used in GCMs. It is known that flash characteristics are quite variable, and that various quantities (like the flash energy or the NOx production per flash) vary considerably, statistically as well as systematically on regional and seasonal scales. LIS provides information beyond flash counts, in particular radiance and flash footprint. Here we present an analysis of global patterns of various lightning properties derived from LIS, in relation to the number of flashes. These normalized flash characteristics show consistent spatial patterns of regions with "strong" versus regions with "weak" lightning. Most striking is a clear land-ocean contrast, with oceanic flashes being "stronger" than continental flashes. But also over continents, flash strength shows systematic variations. Highest continental values are found over the US, while values over South America and India are quite low. These regional variations cannot be simply parameterized as function of latitude. Information on spatial patterns of mean flash "strength", though rather qualitative up to now, is potentially a valuable input for improving empirical parameterizations based on flash counts (like precipitation or lightning NOx). Further investigation is in progress to come to a more physical and quantitative understanding of the spatial patterns of the different LIS properties. In particular, it has to be checked how far they could be related to established lightning properties (like energy or the fraction of intra-cloud to cloud-to-ground flashes) or to meteorological quantities (like CAPE)
The Principal Axis of the Virgo Cluster
Using accurate distances to individual Virgo cluster galaxies obtained by the
method of Surface Brightness Fluctuations, we show that Virgo's brightest
ellipticals have a remarkably collinear arrangement in three dimensions. This
axis, which is inclined by 10 to 15 degrees from the line of sight, can be
traced to even larger scales where it appears to join a filamentary bridge of
galaxies connecting Virgo to the rich cluster Abell 1367. The orientations of
individual Virgo ellipticals also show some tendency to be aligned with the
cluster axis, as does the jet of the supergiant elliptical M87. These results
suggest that the formation of the Virgo cluster, and its brightest member
galaxies, have been driven by infall of material along the Virgo-A1367
filament.Comment: 8 pages, 4 figures, accepted for publication in ApJ Letter
Surface Brightness Fluctuations from archival ACS images: a stellar population and distance study
We derive Surface Brightness Fluctuations (SBF) and integrated magnitudes in
the V- and I-bands using Advanced Camera for Surveys (ACS) archival data. The
sample includes 14 galaxies covering a wide range of physical properties:
morphology, total absolute magnitude, integrated color. We take advantage of
the latter characteristic of the sample to check existing empirical
calibrations of absolute SBF magnitudes both in the I- and V-passbands.
Additionally, by comparing our SBF and color data with the Teramo-SPoT simple
stellar population models, and other recent sets of population synthesis
models, we discuss the feasibility of stellar population studies based on
fluctuation magnitudes analysis. The main result of this study is that
multiband optical SBF data and integrated colors can be used to significantly
constrain the chemical composition of the dominant stellar system in the
galaxy, but not the age in the case of systems older than 3 Gyr.
SBF color gradients are also detected and analyzed. These SBF gradient data,
together with other available data, point to the existence of mass dependent
metallicity gradients in galaxies, with the more massive objects showing a
non--negligible SBF versus color gradient. The comparison with models suggests
that such gradients imply more metal rich stellar populations in the galaxies'
inner regions with respect to the outer ones.Comment: ApJ Accepte
Imprints of Environment on Cluster and Field Late-type Galaxies at z~1
We present a comparison of late-type galaxies (Sa and later) in intermediate
redshift clusters and the field using ACS imaging of four cluster fields:
CL0152-1357, CL1056-0337 (MS1054), CL1604+4304, and CL1604+4321. Concentration,
asymmetry, and clumpiness parameters are calculated for each galaxy in blue
(F606W or F625W) and red (F775W or F814W) filters. Galaxy half-light radii,
disk scale lengths, color gradients, and overall color are compared. We find
marginally significant differences in the asymmetry distributions of spiral and
irregular galaxies in the X-ray luminous and X-ray faint clusters. The massive
clusters contain fewer galaxies with large asymmetries. The physical sizes of
the cluster and field populations are similar; no significant differences are
found in half-light radii or disk scale lengths. The most significant
difference is in rest-frame color. Late-type cluster galaxies are
significantly redder, magnitudes at rest-frame , than their
field counterparts. Moreover, the intermediate-redshift cluster galaxies tend
to have blue inward color gradients, in contrast to the field galaxies, but
similar to late-type galaxies in low redshift clusters. These blue inward color
gradients are likely to be the result of enhanced nuclear star formation rates
relative to the outer disk. Based on the significant rest-frame color
difference, we conclude that late-type cluster members at are not a
pristine infalling field population; some difference in past and/or current
star formation history is already present. This points to high redshift
``groups'', or filaments with densities similar to present-day groups, as the
sites where the first major effects of environment are imprinted.Comment: updated titl
The Next Generation Virgo Cluster Survey (NGVS). XVIII. Measurement and Calibration of Surface Brightness Fluctuation Distances for Bright Galaxies in Virgo (and Beyond)
We describe a program to measure surface brightness fluctuation (SBF)
distances to galaxies observed in the Next Generation Virgo Cluster Survey
(NGVS), a photometric imaging survey covering of the Virgo cluster
in the bandpasses with the Canada-France Hawaii Telescope. We
describe the selection of the sample galaxies, the procedures for measuring the
apparent -band SBF magnitude , and the calibration of the absolute
as a function of observed stellar population properties. The
multi-band NGVS data set provides multiple options for calibrating the SBF
distances, and we explore various calibrations involving individual color
indices as well as combinations of two different colors. Within the color range
of the present sample, the two-color calibrations do not significantly improve
the scatter with respect to wide-baseline, single-color calibrations involving
. We adopt the calibration as reference for the present
galaxy sample, with an observed scatter of 0.11 mag. For a few cases that lack
good photometry, we use an alternative relation based on a combination
of and colors, with only a slightly larger observed scatter of
0.12 mag. The agreement of our measurements with the best existing distance
estimates provides confidence that our measurements are accurate. We present a
preliminary catalog of distances for 89 galaxies brighter than
mag within the survey footprint, including members of the background M and W
Clouds at roughly twice the distance of the main body of the Virgo cluster. The
extension of the present work to fainter and bluer galaxies is in progress.Comment: ApJ accepte
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