15,988 research outputs found
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Advertising and Word-of-Mouth Effects on Pre-launch Consumer Interest and Initial Sales of Experience Products
This study examines how consumers' interest in a new experience product develops as a result of advertising and word-of-mouth activities during the pre-launch period. The empirical settings are the U.S. motion picture and video game industries. The focal variables include weekly ad spend, blog volume, online search volume during pre-launch periods, opening-week sales, and product characteristics. We treat pre-launch search volume of keywords as a measure of pre-launch consumer interest in the related product. To identify probable persistent effects among the pre-launch time-series variables, we apply a vector autoregressive modeling approach. We find that blog postings have permanent, trend-setting effects on pre-launch consumer interest in a new product, while advertising has only temporary effects. In the U.S. motion picture industry, the four-week cumulative elasticity of pre-launch consumer interest is 0.187 to advertising and 0.635 to blog postings. In the U.S. video game industry, the elasticities are 0.093 and 1.306, respectively. We also find long-run co-evolution between blog and search volume, which suggests that consumers' interest in the upcoming product cannot grow without bounds for a given level of blog volume
Sun-as-a-Star Observation of Flares in Lyman {\alpha} by the PROBA2/LYRA radiometer
There are very few reports of flare signatures in the solar irradiance at H i
Lyman {\alpha} at 121.5 nm, i.e. the strongest line of the solar spectrum. The
LYRA radiometer onboard PROBA2 has observed several flares for which
unambiguous signatures have been found in its Lyman-{\alpha} channel. Here we
present a brief overview of these observations followed by a detailed study of
one of them, the M2 flare that occurred on 8 February 2010. For this flare, the
flux in the LYRA Lyman-{\alpha} channel increased by 0.6%, which represents
about twice the energy radiated in the GOES soft X-ray channel and is
comparable with the energy radiated in the He ii line at 30.4 nm. The
Lyman-{\alpha} emission represents only a minor part of the total radiated
energy of this flare, for which a white-light continuum was detected.
Additionally, we found that the Lyman-{\alpha} flare profile follows the
gradual phase but peaks before other wavelengths. This M2 flare was very
localized and has a very brief impulsive phase, but more statistics are needed
to determine if these factors influence the presence of a Lyman-{\alpha} flare
signal strong enough to appear in the solar irradiance.Comment: in press for Solar Physic
Quasi-periodic pulsations in solar and stellar flares: re-evaluating their nature in the context of power-law flare Fourier spectra
The nature of quasi-periodic pulsations in solar and stellar flares remains
debated. Recent work has shown that power-law-like Fourier power spectra, also
referred to as 'red' noise processes, are an intrinsic property of solar and
stellar flare signals, a property that many previous studies of this phenomenon
have not accounted for. Hence a re-evaluation of the existing interpretations
and assumptions regarding QPP is needed. Here we adopt a Bayesian method for
investigating this phenomenon, fully considering the Fourier power law
properties of flare signals. Using data from the PROBA2/LYRA, Fermi/GBM,
Nobeyama Radioheliograph and Yohkoh/HXT instruments, we study a selection of
flares from the literature identified as QPP events. Additionally we examine
optical data from a recent stellar flare that appears to exhibit oscillatory
properties. We find that, for all but one event tested, an explicit oscillation
is not required in order to explain the observations. Instead, the flare
signals are adequately described as a manifestation of a power law in the
Fourier power spectrum, rather than a direct signature of oscillating
components or structures. However, for the flare of 1998 May 8, strong evidence
for the existence of an explicit oscillation with P ~ 14-16 s is found in the
17 GHz radio data and the 13-23 keV Yohkoh HXT data. We conclude that, most
likely, many previously analysed events in the literature may be similarly
described in terms of power laws in the flare Fourier power spectrum, without
the need to invoke a narrowband, oscillatory component. As a result the
prevalence of oscillatory signatures in solar and stellar flares may be less
than previously believed. The physical mechanism behind the appearance of the
observed power laws is discussed.Comment: 11 pages, 7 figures, 1 table. Accepted for publication in The
Astrophysical Journa
Incentive Contracts and Total Factor Productivity
This paper proposes a transactions cost theory of total factor productivity. In a world with asymmetric information and transactions costs, effort, and thus productivity, must be induced by incentive schemes. Labor contracts trade off the marginal benefits and the marginal costs of effort. The latter include, in addition to the workers? marginal disutility of effort, also organizational costs and rents. As the economy grows, the optimal contracts change endogenously, inducing higher effort and measured productivity. Transactions costs are also affected by societal characteristics that determine the power of incentive contracts. Therefore, differences in these characteristics may explain cross-economy productivity differences. Numerical experiments demonstrate that the model is consistent both with time series and cross-country observations. --incentive contracts,total factor productivity,economic growth
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Marketing and Data Science: Together the Future is Ours
The synergistic use of computer science and marketing science techniques offers the best avenue for knowledge development and improved applications. A broad area of complementarity between the typical focus in statistics and computer science and that in marketing offers great potential. The former fields tend to focus on pattern recognition, control and prediction. Many marketing analyses embrace these directions, but also contribute by modeling structure and exploring causal relationships. Marketing has successfully combined foci from management science with foci from psychology and economics. These fields complement each other because they enable a broad spectrum of scientific approaches. Combined, they provide both understanding and practical solutions to important and relevant managerial marketing problems, and marketing science is already very successful at obtaining unique insights from big data
Pairing correlations in a trapped one-dimensional Fermi gas
We use a BCS-type variational wavefunction to study attractively-interacting
quasi one-dimensional (1D) fermionic atomic gases, motivated by cold-atom
experiments that access the 1D regime using an anisotropic harmonic trapping
potential (with trapping frequencies ) that
confines the gas to a cigar-shaped geometry. To handle the presence of the trap
along the -direction, we construct our variational wavefunction from the
harmonic oscillator Hermite functions that are the eigenstates of the
single-particle problem. Using an analytic determination of the effective
interaction among harmonic oscillator states along with a numerical solution of
the resulting variational equations, we make specific experimental predictions
for how pairing correlations would be revealed in experimental probes like the
local density and the momentum correlation function.Comment: 8 pages, 6 figures. Published in Phys. Rev.
Measuring belief in conspiracy theories: Validation of a French and English single-item scale
We designed, in French and in English, a single-item scale to measure people’s general tendency to believe in conspiracy theories. The validity and reliability of this scale was assessed in 3 studies (total N = 555). In Study 1 (N = 152), positive correlations between the single-item scale and 3 other conspiracy belief scales on a French student sample suggested good concurrent validity. In Study 2 (N = 292), we replicated these results on a larger and more heterogeneous Internet American sample. Moreover, the scale showed good predictive validity—responses predicted participants’ willingness to receive a bi-monthly newsletter about alleged conspiracy theories. Finally, in Study 3 (N = 111), we observed good test-retest reliability and demonstrated both convergent and discriminant validity of the single-item scale. Overall these results suggest that the single-item conspiracy belief scale has good validity and reliability and may be used to measure conspiracy belief in favor of lengthier existing scales. In addition, the validation of the single-item scale led us to develop and start validating French versions of the Generic Conspiracist Beliefs scale, the Conspiracy Mentality Questionnaire, and a 10-item version (instead of the 15-item original version) of the Belief in Conspiracy Theories Inventory
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