4,458 research outputs found
The Distortionary Effects of Government Procurement: Evidance From Medicaid Prescription Drug Purchasing
In 2003 the federal-state Medicaid program provided prescription drug coverage to more than 50 million people. To determine the price that it will pay for each drug, Medicaid uses the average private sector price. When Medicaid is a large part of the demand for a drug, this creates an incentive for its maker to increase prices for other health care consumers. Using drug utilization and expenditure data for the top 200 drugs in 1997 and in 2002, we investigate the relationship between the Medicaid market share (MMS) and the average price of a prescription. Our estimates imply that a 10-percentage-point increase in the MMS is associated with a 7 to 10 percent increase in the average price of a prescription. In addition, the Medicaid rules increase a firm\u27s incentive to introduce new versions of a drug in order to raise price. We find empirical evidence that firms producing newer drugs with larger sales to Medicaid are more likely to introduce new versions. Taken together, our findings suggest that government procurement rules can alter equilibrium price and product proliferation in the private sector
Numerical Prediction and Wind Tunnel Experiment for a Pitching Unmanned Combat Air Vehicle
The low-speed flowfield for a generic unmanned combat air vehicle (UCAV) is investigated both experimentally and numerically. A wind tunnel experiment was conducted with the Boeing 1301 UCAV at a variety of angles of attack up to 70 degrees, both statically and with various frequencies of pitch oscillation (0.5, 1.0, and 2.0 Hz). In addition, pitching was performed about three longitudinal locations on the configuration (the nose, 35% MAC, and the tail). Solutions to the unsteady, laminar, compressible Navier–Stokes equations were obtained on an unstructured mesh to match results from the static and dynamic experiments. The computational results are compared with experimental results for both static and pitching cases. Details about the flowfield, including vortex formation and interaction, are shown and discussed, including the non-linear aerodynamic characteristics of the vehicle
Addictive Technology and Its Implications for Antitrust Enforcement
The advent of mobile devices and digital media platforms in the past decade represents the biggest shock to cognition in human history. Robust medical evidence is emerging that digital media platforms are addictive and, when used in excess, harmful to users’ mental health. Other types of addictive products, like tobacco and prescription drugs, are heavily regulated to protect consumers. Currently, there is no regulatory structure protecting digital media users from these harms. Antitrust enforcement and regulation that lowers entry barriers could help consumers of social media by increasing competition. Economic theory tells us that more choice in digital media will increase the likelihood that some firms will vie to offer higher-quality and safer platforms. For this reason, evaluating harm to innovation (especially safety innovation) and product variety may be particularly important in social media merger and conduct cases. Another critical element to antitrust enforcement in this space is a correct accounting of social media’s addictive qualities. Standard antitrust analysis seeks to prohibit conduct that harms consumer welfare. Economists have taught the antitrust bar that the output of a product or service is a reliable proxy for consumer welfare. However, output and welfare do not have this relationship when a product is addictive. Indeed, in social media markets, increased output is often harmful. We argue that antitrust analysis must reject the output proxy and return to a focus on consumer welfare itself in cases involving addictive social media platforms. In particular, courts should reject defenses that rely only on gross output measures without evidence that any alleged increases in output actually benefit consumers
Entry Decisions in the Generic Pharmaceutical Industry
In this paper I use data on all generic drug approvals granted from 1984- 1994 to examine whether heterogeneity among potential generic entrants can be used to predict which firms will choose to enter a particular market. The findings suggest that a firm's portfolio characteristics, namely, its previous experience with a drug or therapy reduces the cost of preparing an ANDA and increases the probability of entry. A subsidiary's parent's experience is not generally significant in predicting entry of the subsidiary. Firms also prefer entering markets that are similar, in terms of revenue and sales to hospitals, to markets already in their portfolios. On both scientific and marketing dimensions evidence shows that firms are specializing. I explore several different ways of constructing the set of potential entrants and find the results are not affected by methodological variation. Standard IO theory suggests that profits per entrant will decline in the number of entrants. Previous research has found that generic prices depend on the number of generic entrants, and the results presented here show that the total number of entrants increases with the size of the market (revenue). These findings imply that generic firms face a negative competition externality which makes their expectations about who else might be planning to enter any given market important in the entry decision. The limited evidence on entrant beliefs supports this conjecture as do several features of a regulatory upheaval when firms began entering different markets than they had in the past.
Bio-inspired all-optical artificial neuromast for 2D flow sensing
We present the design, fabrication and testing of a novel all-optical 2D flow velocity sensor, inspired by a fish lateral line neuromast. This artificial neuromast consists of optical fibres inscribed with Bragg gratings supporting a fluid force recipient sphere. Its dynamic response is modelled based on the Stokes solution for unsteady flow around a sphere and found to agree with experimental results. Tuneable mechanical resonance is predicted, allowing a deconvolution scheme to accurately retrieve fluid flow speed and direction from sensor readings. The optical artificial neuromast achieves a low frequency threshold flow sensing of 5 mm s(-1) and 5 mu m s(-1) at resonance, with a typical linear dynamic range of 38 dB at 100 Hz sampling. Furthermore, the optical artificial neuromast is shown to determine flow direction within a few degrees
Love or Money? The Effects of Owner Motivation in the California Wine Industry
Many industries are characterized by heterogeneous objectives on the part of firm owners. Owners of private firms, in particular, are likely to maximize utility, rather than profits. In this paper, we model and measure motivations of owners in on particular industry, the California wine industry. In both a formal model and an empirical analysis, we examine the implications of these motivations for market behavior. We find evidence that owners with strong non-financial motivations choose higher prices for their wines, controlling for quality; owners with strong profit-maximizing motives choose lower prices for their wines, controlling for quality. We also find that utility-maximizers are more likely to locate at the higher end of the quality spectrum, whereas profit-maximizers are more likely to locate at the lower end. We explore how the presence of a significant number of utility maximizers within an industry affects the competitive interactions within that industry. We conclude that some winery owners consume' features of their product or business as a substitute for profits and, in the process, provide softer price competition for for-profits. Additionally, in aggregate, their preference for quality can prevent entry into the high-quality segment on the part of profit-maximizing firms.
CARMA CO(J = 2 - 1) Observations of the Circumstellar Envelope of Betelgeuse
We report radio interferometric observations of the 12C16O 1.3 mm J = 2-1
emission line in the circumstellar envelope of the M supergiant Alpha Ori and
have detected and separated both the S1 and S2 flow components for the first
time. Observations were made with the Combined Array for Research in
Millimeter-wave Astronomy (CARMA) interferometer in the C, D, and E antenna
configurations. We obtain good u-v coverage (5-280 klambda) by combining data
from all three configurations allowing us to trace spatial scales as small as
0.9\arcsec over a 32\arcsec field of view. The high spectral and spatial
resolution C configuration line profile shows that the inner S1 flow has
slightly asymmetric outflow velocities ranging from -9.0 km s-1 to +10.6 km s-1
with respect to the stellar rest frame. We find little evidence for the outer
S2 flow in this configuration because the majority of this emission has been
spatially-filtered (resolved out) by the array. We also report a SOFIA-GREAT
CO(J= 12-11) emission line profile which we associate with this inner higher
excitation S1 flow. The outer S2 flow appears in the D and E configuration maps
and its outflow velocity is found to be in good agreement with high resolution
optical spectroscopy of K I obtained at the McDonald Observatory. We image both
S1 and S2 in the multi-configuration maps and see a gradual change in the
angular size of the emission in the high absolute velocity maps. We assign an
outer radius of 4\arcsec to S1 and propose that S2 extends beyond CARMA's field
of view (32\arcsec at 1.3 mm) out to a radius of 17\arcsec which is larger than
recent single-dish observations have indicated. When azimuthally averaged, the
intensity fall-off for both flows is found to be proportional to R^{-1}, where
R is the projected radius, indicating optically thin winds with \rho \propto
R^{-2}.Comment: 11 pages, 8 figures To be published in the Astronomical Journal
(Received 2012 February 10; accepted 2012 May 25
Microseismic joint location and anisotropic velocity inversion for hydraulic fracturing in a tight Bakken reservoir
To improve the accuracy of microseismic event locations, we developed a new inversion method with double-difference constraints for determining the hypocenters and the anisotropic velocity model for unconventional reservoirs. We applied this method to a microseismic data set monitoring a Middle Bakken completion in the Beaver Lodge area of North Dakota. Geophone arrays in four observation wells improved the ray coverage for the velocity inversion. Using an accurate anisotropic velocity model is important to correctly assess the height growth of the hydraulically induced fractures in the Middle Bakken. Our results showed that (1) moderate-to-strong anisotropy exists in all studied sedimentary layers, especially in the Upper and Lower Bakken shale formations, where the Thomsen parameters (ϵ and γ) can be greater than 0.4, (2) all the events selected for high signal-to-noise ratio and used for the joint velocity inversion are located in the Bakken and overlying Lodgepole formations, i.e., no events are detected in the Three Forks formation below the Bakken, and (3) more than half of the strong events are in two clusters at approximately 100 and 150 m above the Middle Bakken. Reoccurrence of strong, closely clustered events suggested activation of natural fractures or faults in the Lodgepole formation. The sensitivity analysis for the inversion results showed that the relative uncertainty in parameter δ is larger than other anisotropy parameters. The microseismic event locations and the anisotropic velocity model are validated by comparing synthetic and observed seismic waveforms and by S-wave splitting.Shell Oil Compan
The Keck+Magellan Survey for Lyman Limit Absorption II: A Case Study on Metallicity Variations
We present an absorption line analysis of the Lyman limit system (LLS) at
z=3.55 in our Magellan/MIKE spectrum of PKS2000-330. Our analysis of the Lyman
limit and full HI Lyman series constrains the total HI column density of the
LLS (N_HI = 10^[18.0 +/- 0.25] cm^{-2} for b_HI >= 20 km/s) and also the N_HI
values of the velocity subsystems comprising the absorber. We measure ionic
column densities for metal-line transitions associated with the subsystems and
use these values to constrain the ionization state (>90% ionized) and relative
abundances of the gas. We find an order of magnitude dispersion in the
metallicities of the subsystems, marking the first detailed analysis of
metallicity variations in an optically thick absorber. The results indicate
that metals are not well mixed within the gas surrounding high galaxies.
Assuming a single-phase photoionization model, we also derive an N_H-weighted
metallicity, = -1.66 +/- 0.25, which matches the mean metallicity in
the neutral ISM in high z damped Lya systems (DLAs). Because the line density
of LLSs is ~10 times higher than the DLAs, we propose that the former dominate
the metal mass-density at z~3 and that these metals reside in the galaxy/IGM
interface. Considerations of a multi-phase model do not qualitatively change
these conclusions. Finally, we comment on an anomalously large O^0/Si^+ ratio
in the LLS that suggests an ionizing radiation field dominated by soft UV
sources (e.g. a starburst galaxy). Additional abundance analysis is performed
on the super-LLS systems at z=3.19.Comment: 20 pages, 7 figures (most in color). Accepted to Ap
Effect of the look-up line on the gaze and head orientation of elite ice hockey players
A “look-up-line” (LUL) has been proposed for ice hockey, which is an orange 1 m (40 in) warning line (WL) painted on the ice at the base of the boards. The LUL purports to provide an early warning to players to keep their head up prior to, and as they are being checked. We determined if players looked-up more on a rink with the LUL compared to a traditional Control rink. Elite offensive (O) and defensive (D) players competed 1 vs 1, while wearing an eye tracker that recorded their quiet eye (QE) and fixation tracking (F-T) and an electro-goniometer that measured head angle. External cameras recorded skate duration during four skate phases: P1 preparation, P2 decision-making, P3 cut to boards, P4 contact. The QE was the final fixation prior to contact between O and D as they skated toward and across the WL during P3 and P4. Skate phase durations (%) did not differ by rink or rink by position. More QE and F-T occurred on the WL on the LUL rink than on the Control. The expected increase in head angle on the LUL rink did not occur during P3 or P4. Post-hoc results also showed O and D skated further from the boards on the LUL rink, suggesting the players preferred to control the puck on white ice, rather than the orange color of the LUL rink. More research is needed to determine if these results apply to the competitive setting
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