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Robert H. Romer

Other affiliations: Princeton University
Bio: Robert H. Romer is an academic researcher from Amherst College. The author has contributed to research in topics: Elementary particle & Sign (mathematics). The author has an hindex of 14, co-authored 59 publications receiving 10445 citations. Previous affiliations of Robert H. Romer include Princeton University.


Papers
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Journal ArticleDOI
TL;DR: The pages of this expensive but invaluable reference work are dense with formulae of stupefying complexity as discussed by the authors, where definite/indefinite integral properties of a great variety of special functions are discussed.
Abstract: The pages of this expensive but invaluable reference work are dense with formulae of stupefying complexity. Chapters 1 and 2 treat definite/indefinite integral properties of a great variety of special functions, Chapters 3 and 4 (which are relatively brief) treat definite integrals of some piece-wi

3,784 citations

Journal ArticleDOI
TL;DR: The Formulaire Reference Record was created on 2004-09-07, modified on 2016-08-08 as discussed by the authors, and is based on the formulaire reference record (FRS).
Abstract: Keywords: Mathematique ; Formulaire Reference Record created on 2004-09-07, modified on 2016-08-08

120 citations

Journal ArticleDOI
TL;DR: In this paper, a microwave resonance line was obtained having widths substantially less than the normal Doppler width, which depends on the properties of a radiating gas when contained in a cavity in the form of a pillbox, of diameter large compared to height.
Abstract: An experiment is described in which microwave resonance lines have been obtained having widths substantially less than the normal Doppler width. The line shape obtained depends on the properties of a radiating gas when contained in a cavity in the form of a pillbox, of diameter large compared to height. Collisions of molecules with the walls take place in such a manner that the collisions narrow the line instead of broadening it. The 1.25-cm inversion transition in ammonia was observed, and lines one quarter the normal Doppler width of 73 kc/sec obtained; further narrowing appears feasible. The line shapes and widths are in good agreement with the calculations.

80 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, an exponential ARCH model is proposed to study volatility changes and the risk premium on the CRSP Value-Weighted Market Index from 1962 to 1987, which is an improvement over the widely-used GARCH model.
Abstract: This paper introduces an ARCH model (exponential ARCH) that (1) allows correlation between returns and volatility innovations (an important feature of stock market volatility changes), (2) eliminates the need for inequality constraints on parameters, and (3) allows for a straightforward interpretation of the "persistence" of shocks to volatility. In the above respects, it is an improvement over the widely-used GARCH model. The model is applied to study volatility changes and the risk premium on the CRSP Value-Weighted Market Index from 1962 to 1987. Copyright 1991 by The Econometric Society.

10,019 citations

Journal ArticleDOI
S. ten Brink1
TL;DR: A code search based on the EXIT chart technique has been performed yielding new recursive systematic convolutional constituent codes exhibiting turbo cliffs at lower signal-to-noise ratios than attainable by previously known constituent codes.
Abstract: Mutual information transfer characteristics of soft in/soft out decoders are proposed as a tool to better understand the convergence behavior of iterative decoding schemes. The exchange of extrinsic information is visualized as a decoding trajectory in the extrinsic information transfer chart (EXIT chart). This allows the prediction of turbo cliff position and bit error rate after an arbitrary number of iterations. The influence of code memory, code polynomials as well as different constituent codes on the convergence behavior is studied for parallel concatenated codes. A code search based on the EXIT chart technique has been performed yielding new recursive systematic convolutional constituent codes exhibiting turbo cliffs at lower signal-to-noise ratios than attainable by previously known constituent codes.

2,498 citations

Journal ArticleDOI
01 Oct 1991-Genetics
TL;DR: In an exponentially growing population in which the product of the current population size and the growth rate is substantially larger than one, the analytical and simulation results show that most coalescent events occur relatively early and in a restricted range of times.
Abstract: We consider the distribution of pairwise sequence differences of mitochondrial DNA or of other nonrecombining portions of the genome in a population that has been of constant size and in a population that has been growing in size exponentially for a long time. We show that, in a population of constant size, the sample distribution of pairwise differences will typically deviate substantially from the geometric distribution expected, because the history of coalescent events in a single sample of genes imposes a substantial correlation on pairwise differences. Consequently, a goodness-of-fit test of observed pairwise differences to the geometric distribution, which assumes that each pairwise comparison is independent, is not a valid test of the hypothesis that the genes were sampled from a panmictic population of constant size. In an exponentially growing population in which the product of the current population size and the growth rate is substantially larger than one, our analytical and simulation results show that most coalescent events occur relatively early and in a restricted range of times. Hence, the "gene tree" will be nearly a "star phylogeny" and the distribution of pairwise differences will be nearly a Poisson distribution. In that case, it is possible to estimate r, the population growth rate, if the mutation rate, mu, and current population size, N0, are assumed known. The estimate of r is the solution to ri/mu = ln(N0r) - gamma, where i is the average pairwise difference and gamma approximately 0.577 is Euler's constant.

2,260 citations

Journal ArticleDOI
TL;DR: A survey and review of the major econometric work on long memory processes, fractional integration, and their applications in economics and finance and some of the definitions of long memory are reviewed.

1,950 citations

Journal ArticleDOI
TL;DR: A key finding is that the feedback rate per mobile must be increased linearly with the signal-to-noise ratio (SNR) (in decibels) in order to achieve the full multiplexing gain.
Abstract: Multiple transmit antennas in a downlink channel can provide tremendous capacity (i.e., multiplexing) gains, even when receivers have only single antennas. However, receiver and transmitter channel state information is generally required. In this correspondence, a system where each receiver has perfect channel knowledge, but the transmitter only receives quantized information regarding the channel instantiation is analyzed. The well-known zero-forcing transmission technique is considered, and simple expressions for the throughput degradation due to finite-rate feedback are derived. A key finding is that the feedback rate per mobile must be increased linearly with the signal-to-noise ratio (SNR) (in decibels) in order to achieve the full multiplexing gain. This is in sharp contrast to point-to-point multiple-input multiple-output (MIMO) systems, in which it is not necessary to increase the feedback rate as a function of the SNR

1,717 citations