43,543 research outputs found
In the field:Coase an exemplar in the tradition of Smith, Marshall and Ostrom
This paper argues that Coase provides the primary 20th century exemplar of the grounding of analytical developments in economics in direct fieldwork observation. In particular, his focus on the business enterprise, its internal functions (including decision-making), and its external relations (including contracting) has provided a stimulus for radical developments in microeconomics and in managerial and decision economics in particular. The argument is developed by a stylization of the development of economics, referring to Adam Smith in the 18th century, Alfred Marshall in the 19th century, Ronald Coase in the 20th century, and Elinor Ostrom in the 21st century
Solar Activity and the Sea-surface Temperature Record-evidence of a Long-period Variation in Solar Total Irradiance
There have been many suggestions over the years of a connection between solar activity and the Earth's climate on time scales long compared to the 11-year sunspot cycle. They have remained little more than suggestions largely because of the major uncertainties in the climate record itself, and the difficulty in trying to compile a global average from an assembly of measurements that are uneven in both quality and distribution. Different climate time response to solar activity, some suggesting a positive correlation, some a negative correlation, and some no correlation at all. The only excuse for making yet another such suggestion is that much effort has been devoted in recent years to compiling climate records for the past century or more that are internally consistent and believable, and that a decadal-scale record of solar total irradiance is emerging from spacecraft measurements, and can be used to set limits on the variation that is likely to have occurred on these time scales. The work described here was originally inspired by the observation that the time series of globally averaged sea-surface temperatures over the past 120 years or so, as compiled by the British Meteorological Office group (Folland and Kates, 1984), bore a resonable similarity to the long-term average sunspot number, which is an indicator of the secular variability of solar activity. The two time series are shown where the sunspot number is shown as the 135-month running mean, and the SST variation is shown as the departure from an arbitrary average value. The simplest explanation of the similarity, if one accepts it as other than coincidental, is that the sun's luminosity may have been varying more or less in step with the level of solar activity, or in other words that there is a close coupling between the sun's magnetic condition and its radiative output on time scales longer than the 11-year cycle. Such an idea is not new, and in fact the time series shown can be regarded as a modern extension of the proposal put forward by Eddy (1977) to explain the covariance between various global climate indicators and solar activity as revealed by the C-14 record over the past millenium
Performance and strategy:simultaneous equations analysis of long-lived firms
A simultaneous equations model of performance, strategy and size is tested using fieldwork evidence on long-lived firms in Scotland. Estimation is by I3SLS, with correction for sample selection bias. The contributions of this paper are that it: (a) grounds estimation on fieldwork evidence; (b) calibrates performance and competitive strategy; (c) tests and models endogeneity; and (d) computes robust trade-off elasticities between firm size and performance. It shows how this trade-off provides the entrepreneur with two strong incentives: (i) to seek greater efficiency typically by an increase in the human capital of the ‘core’ workforce; (ii) to achieve higher levels of performance by adopting more diverse competitive strategies
Multifrequency microwave radiometer (MFMR) L-band modification
The redesign of the L-band part of the multifrequency microwave radiometer (MFMR) was conducted to provide an instrument with improved sensitivity and accuracy. The results are discussed
Controlling tetramer formation, subunit rotation and DNA ligation during Hin-catalyzed DNA inversion.
Two critical steps controlling serine recombinase activity are the remodeling of dimers into the chemically active synaptic tetramer and the regulation of subunit rotation during DNA exchange. We identify a set of hydrophobic residues within the oligomerization helix that controls these steps by the Hin DNA invertase. Phe105 and Met109 insert into hydrophobic pockets within the catalytic domain of the same subunit to stabilize the inactive dimer conformation. These rotate out of the catalytic domain in the dimer and into the subunit rotation interface of the tetramer. About half of residue 105 and 109 substitutions gain the ability to generate stable synaptic tetramers and/or promote DNA chemistry without activation by the Fis/enhancer element. Phe106 replaces Phe105 in the catalytic domain pocket to stabilize the tetramer conformation. Significantly, many of the residue 105 and 109 substitutions support subunit rotation but impair ligation, implying a defect in rotational pausing at the tetrameric conformer poised for ligation. We propose that a ratchet-like surface involving Phe105, Met109 and Leu112 within the rotation interface functions to gate the subunit rotation reaction. Hydrophobic residues are present in analogous positions in other serine recombinases and likely perform similar functions
Decision support for firm performance by real options analytics
This paper develops a real options decision support tool for raising the performance of the firm. It shows how entrepreneurs can use our intuitive tool quickly to assess the nature and type of action required for improved performance. This exploits our estimated econometric relationship between precipitators of entrepreneurial opportunities, time until exercise, and firm performance. Our 3D chromaticity plots show how staging investments, investment time, and firm performance support entrepreneurial decisions to embed, or to expedite, investments. Speedy entrepreneurial action is securely supported with this tool, without expertise in econometric estimation or in formulae for real options valuation
Realities of long-term post investment performance for venture-backed enterprises
This paper constructs a model of long-run performance for SMEs that have received venture capital backing. The model explains performance by financial structure. FAME data are used for estimating performance equations over the period 1989 to 2004 for UK businesses in their post-investment period. The econometrics uses robust techniques, including least absolute error (LAE) and Tukey trimean estimation. It is shown that the key determinants of performance (measured by ROSF) are profit margins and risk, with lesser, but significant, roles played by liquidity and gearing. The sample is used to identify consistently high performers, and chronic low performers. From the latter group, two detailed case studies illustrate how chronic low performance can emerge, in each case caused by failure to achieve technological milestones, and thereby failing, ultimately, to convince investors of potential company worth
High-Growth Elementary Schools in Arkansas Based on Performance on the ACT Aspire Examinations
This section highlights elementary schools across the state whose students demonstrated high growth on the Arkansas ACT Aspire exams. The ACT Aspire was administered to students in grades 3 through 10 in April 2018 in Math and ELA courses which include English, Writing, and Reading
- …