125,826 research outputs found
From New London to Norwood: A Year in the Life of Eminent Domain
A little more than a year after the U.S. Supreme Court\u27s decision in Kelo v. City of New London upheld the use of eminent domain for economic development, the Ohio Supreme Court became the first state supreme court to address a factual situation raising the same issues. In City of Norwood v. Horney, the Ohio court repudiated the Kelo rationale and rejected Norwood\u27s proposed takings. Property rights advocates quickly hailed Norwood as a model for other state courts to follow in defending individual land owners from eminent domain abuse. This Note argues that Norwood\u27s holding is incoherent and does nothing to resolve the language-based quagmire that inflames the eminent domain debate. This Note instead contends that the Connecticut Supreme Court\u27s more nuanced Kelo v. City of New London opinion is a superior state court model, which better captures the necessary balance between individual property rights and urban revitalization plans involving eminent domain
Derivatives of Entropy Rate in Special Families of Hidden Markov Chains
Consider a hidden Markov chain obtained as the observation process of an
ordinary Markov chain corrupted by noise. Zuk, et. al. [13], [14] showed how,
in principle, one can explicitly compute the derivatives of the entropy rate of
at extreme values of the noise. Namely, they showed that the derivatives of
standard upper approximations to the entropy rate actually stabilize at an
explicit finite time. We generalize this result to a natural class of hidden
Markov chains called ``Black Holes.'' We also discuss in depth special cases of
binary Markov chains observed in binary symmetric noise, and give an abstract
formula for the first derivative in terms of a measure on the simplex due to
Blackwell.Comment: The relaxed condtions for entropy rate and examples are taken out (to
be part of another paper). The section about general principle and an example
to determine the domain of analyticity is taken out (to be part of another
paper). A section about binary Markov chains corrupted by binary symmetric
noise is adde
Direct solar-pumped iodine laser amplifier
This semiannual progress report covers the period from March 1, 1987 to September 30, 1987 under NASA grant NAG1-441 entitled 'Direct solar-pumped iodine laser amplifier'. During this period Nd:YAG and Nd:Cr:GSGG crystals have been tested for the solar-simulator pumped cw laser, and loss mechanisms of the laser output power in a flashlamp-pumped iodine laser also have been identified theoretically. It was observed that the threshold pump-beam intensities for both Nd:YAG and Nd:Cr:GSGG crystals were about 1000 solar constants, and the cw laser operation of the Nd:Cr:GSGG crystal was more difficult than that of the Nd:YAG crystal under the solar-simulator pumping. The possibility of the Nd:Cr:GSGG laser operation with a fast continuously chopped pumping was also observed. In addition, good agreement between the theoretical calculations and the experimental data on the loss mechanisms of a flashlamp-pumped iodine laser at various fill pressures and various lasants was achieved
High-dimensional Linear Regression for Dependent Data with Applications to Nowcasting
Recent research has focused on penalized least squares (Lasso)
estimators for high-dimensional linear regressions in which the number of
covariates is considerably larger than the sample size . However, few
studies have examined the properties of the estimators when the errors and/or
the covariates are serially dependent. In this study, we investigate the
theoretical properties of the Lasso estimator for a linear regression with a
random design and weak sparsity under serially dependent and/or nonsubGaussian
errors and covariates. In contrast to the traditional case, in which the errors
are independent and identically distributed and have finite exponential
moments, we show that can be at most a power of if the errors have only
finite polynomial moments. In addition, the rate of convergence becomes slower
owing to the serial dependence in the errors and the covariates. We also
consider the sign consistency of the model selection using the Lasso estimator
when there are serial correlations in the errors or the covariates, or both.
Adopting the framework of a functional dependence measure, we describe how the
rates of convergence and the selection consistency of the estimators depend on
the dependence measures and moment conditions of the errors and the covariates.
Simulation results show that a Lasso regression can be significantly more
powerful than a mixed-frequency data sampling regression (MIDAS) and a Dantzig
selector in the presence of irrelevant variables. We apply the results obtained
for the Lasso method to nowcasting with mixed-frequency data, in which serially
correlated errors and a large number of covariates are common. The empirical
results show that the Lasso procedure outperforms the MIDAS regression and the
autoregressive model with exogenous variables in terms of both forecasting and
nowcasting
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