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MAST: Mental Ambidexterity in Strategic Thinking
There are two fundamental ways to think about what strategy is. The first one is strategy as a plan of action for reaching one or several goals. The second one is strategy as discipline, a formalized body of knowledge. The latter can be understood as the set of governing ideas that guide managers in the identification of opportunities for value creation and the realization of that value. In the present article, we argue that these ideas tend to fall into two main paradigms, which come with two metaphors about managers: managers as commanders and managers as designers. We further argue that these represent two fundamental ways of thinking, which in turn become ways of âseeingâ and even feeling. Is one better than the other? We suggest that is not the right question to ask. Rather it is important to appreciate that these are worldviews that affect how we interpret our day-to-day reality and our ability to see opportunities. We introduce the notion of Mental Ambidexterity in Strategic Thinking (MAST) and define it as the ability to hold both views of the worldâthat of the commander and that of the designerâ and play with them simultaneously, rather than focusing solely on one and rejecting the other. MAST is an individual level capability; it is a flexible, non-ideological and fluid mode of cognition. At the core, it is characterized by switching flexibility back and forth between rational decisionmaking among alternatives, and creation of new alternatives, between what is and what could be. We illustrate three principles â i) intellectual humility, ii) contingent thinking and iii) poke into ambiguity â that act as catalysts for individuals to develop MAST capabilities
Quantum mechanics with time-dependent parameters
Smooth composite bundles provide the adequate geometric description of
classical mechanics with time-dependent parameters. We show that the Berry's
phase phenomenon is described in terms of connections on composite Hilbert
space bundles.Comment: 7 pages, LaTe
A recalibration of IUE NEWSIPS low dispersion data
While the low dispersion IUE NEWSIPS data products represent a significant
improvement over original IUE SIPS data, they still contain serious systematic
effects which compromise their utility for certain applications. We show that
NEWSIPS low resolution data are internally consistent to only 10-15% at best,
with the majority of the problem due to time dependent systematic effects. In
addition, the NEWSIPS flux calibration is shown to be inconsistent by nearly
10%.
We examine the origin of these problems and proceed to formulate and apply
algorithms to correct them to ~ 3% level -- a factor of 5 improvement in
accuracy. Because of the temporal systematics, transforming the corrected data
to the IUE flux calibration becomes ambiguous. Therefore, we elect to transform
the corrected data onto the HST FOS system. This system is far more
self-consistent, and transforming the IUE data to it places data from both
telescopes on a single system.
Finally, we argue that much of the remaining 3% systematic effects in the
corrected data is traceable to problems with the NEWSIPS intensity
transformation function (ITF). The accuracy could probably be doubled by
rederiving the ITF.Comment: Submitted to ApJ Supplement, 35 pages, 13 figures, LaTeX - AASTEX
aas2pp4.st
Measurement of the boosted tÂŻt differential cross section in lepton + jets channel in pp collisions with the ATLAS experiment
The top quark is the heaviest particle in Standard Model. When it is produced with a large Lorentz boost, its decay products tend to overlap, making the standard reconstruction techniques inefficient; large R jet substructure analysis techniques allow to increase the detection efficiency for these events. Differential cross section measurements of boosted tÂŻt from pp collisions with
âs = 8TeV will be shown, using a sample of ⌠20 fbâ1, recorded by ATLAS during 2012
Signature of wide-spread clumping in B supergiant winds
We seek to establish additional observational signatures of the effects of
clumping in OB star winds. The action of clumping on strategic wind-formed
spectral lines is tested to steer the development of models for clumped winds
and thus improve the reliability of mass-loss determinations for massive
stars.The SiIV 1400 resonance line doublets of B0 to B5 supergiants are
analysed using empirical line-synthesis models. The focus is on decoding
information on wind clumping from measurements of ratios of the radial optical
depths (tau_(rad)(w)) of the red and blue components of the SiIV doublet. We
exploit in particular the fact that the two doublet components are decoupled
and formed independently for targets with relatively low wind terminal
velocities. Line-synthesis analyses reveal that the mean ratio of tau_(rad)(w)
of the blue to red SiIV components are rarely close to the canonical value of ~
2 (expected from atomic constants), and spread instead over a range of values
between ~1 and 2. These results are interpreted in terms of a photosphere that
is partially obscured by optically thick structures in the outflowing gas.The
spectroscopic signatures established in this study demonstrate the wide-spread
existence of wind clumping in B supergiants. The additional information in
unsaturated doublet profiles provides a means to quantify the porosity of the
winds.Comment: Accepted for publication in A&A Letter
An Analysis of the Shapes of Interstellar Extinction Curves. VI. The Near-IR Extinction Law
We combine new HST/ACS observations and existing data to investigate the
wavelength dependence of NIR extinction. Previous studies suggest a power-law
form, with a "universal" value of the exponent, although some recent
observations indicate that significant sight line-to-sight line variability may
exist. We show that a power-law model provides an excellent fit to most NIR
extinction curves, but that the value of the power, beta, varies significantly
from sight line-to-sight line. Therefore, it seems that a "universal NIR
extinction law" is not possible. Instead, we find that as beta decreases, R(V)
[=A(V)/E(B-V)] tends to increase, suggesting that NIR extinction curves which
have been considered "peculiar" may, in fact, be typical for different R(V)
values. We show that the power law parameters can depend on the wavelength
interval used to derive them, with the beta increasing as longer wavelengths
are included. This result implies that extrapolating power law fits to
determine R(V) is unreliable. To avoid this problem, we adopt a different
functional form for NIR extinction. This new form mimics a power law whose
exponent increases with wavelength, has only 2 free parameters, can fit all of
our curves over a longer wavelength baseline and to higher precision, and
produces R(V) values which are consistent with independent estimates and
commonly used methods for estimating R(V). Furthermore, unlike the power law
model, it gives R(V)'s that are independent of the wavelength interval used to
derive them. It also suggests that the relation R(V) = -1.36 E(K-V)/E(B-V) -
0.79 can estimate R(V) to +/-0.12. Finally, we use model extinction curves to
show that our extinction curves are in accord with theoretical expectations.Comment: To appear in the Astrophysical Journa
Quantile Regression Estimates of Confidence Intervals for WASDE Price Forecasts
This study uses quantile regressions to estimate historical forecast error distributions for WASDE forecasts of corn, soybean, and wheat prices, and then compute confidence limits for the forecasts based on the empirical distributions. Quantile regressions with fit errors expressed as a function of forecast lead time are consistent with theoretical forecast variance expressions while avoiding assumptions of normality and optimality. Based on out-of-sample accuracy tests over 1995/96â2006/07, quantile regression methods produced intervals consistent with the target confidence level. Overall, this study demonstrates that empirical approaches may be used to construct accurate confidence intervals for WASDE corn, soybean, and wheat price forecasts.commodity, evaluating forecasts, government forecasting, judgmental forecasting, prediction intervals, price forecasting, Crop Production/Industries, Demand and Price Analysis,
Quantile Regression Methods of Estimating Confidence Intervals for WASDE Price Forecasts
This paper explores the use of quantile regression for estimation of empirical confidence limits for WASDE forecasts of corn, soybean, and wheat prices. Quantile regressions for corn, soybean, and wheat forecast errors over 1980/81 through 2006/07 were specified as a function of forecast lead time. Estimated coefficients were used to calculate forecast intervals for 2007/08. The quantile regression approach to calculating forecast intervals was evaluated based on out-of-sample performance. The accuracy of the empirical confidence intervals was not statistically different from the target level about 87% of the time prior to harvest and 91% of the time after harvest.Demand and Price Analysis,
An analysis of the shapes of interstellar extinction curves. VII Milky Way spectrophotometric optical-through-ultraviolet extinction and its R-dependence
We produce a set of 72 NIR-through-UV extinction curves by combining new Hubble Space Telescope/STIS optical spectrophotometry with existing International Ultraviolet Explorer spectrophotometry (yielding gapless coverage from 1150 to 10000 ?) and NIR photometry. These curves are used to determine a new, internally consistent NIR-through-UV Milky Way mean curve and to characterize how the shapes of the extinction curves depend on R(V). We emphasize that while this dependence captures much of the curve variability, considerable variation remains that is independent of R(V). We use the optical spectrophotometry to verify the presence of structure at intermediate wavelength scales in the curves. The fact that the optical-through-UV portions of the curves are sampled at relatively high resolution makes them very useful for determining how extinction affects different broadband systems, and we provide several examples. Finally, we compare our results to previous investigations
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