1,383 research outputs found
Pricing of insurance policies against cloud storage price rises
When a company migrates to cloud storage, the way back is neither easy nor
cheap. The company is then locked up in the storage contract and exposed to
upward market prices, which reduce the company's profit and may even bring it
below zero. We propose a protection means based on an insurance contract, by
which the cloud purchaser is indemnified when the current storage price exceeds
a pre-defined threshold. By applying the financial options theory, we provide a
formula for the insurance price (the premium). By using historical data on
market prices for disks, we apply the formula in realistic scenarios. We show
that the premium grows nearly quadratically with the length of the coverage
period as long as this is below one year, but grows more slowly, though faster
than linearly, over longer coverage periods
First--order continuous models of opinion formation
We study certain nonlinear continuous models of opinion formation derived
from a kinetic description involving exchange of opinion between individual
agents. These models imply that the only possible final opinions are the
extremal ones, and are similar to models of pure drift in magnetization. Both
analytical and numerical methods allow to recover the final distribution of
opinion between the two extremal ones.Comment: 17 pages, 4 figure
Estimation of traf- fic matrices in the presence of long memory traffic
The estimation of traffic matrices in a communications network on the basis of a set of traffic measurements on the network links is a well-known problem, for which a number of solutions have been proposed when the traffic does not show dependence over time, as in the case of the Poisson process. However, extensive measurements campaigns conducted on IP networks have shown that the traffic exhibits long range dependence. Here a method is proposed for the estimation of traffic matrices in the case of long range dependence, and its theoretical properties are studied. Its merits are then evaluated via a simulation study. Finally, an application to real data is provided
A rank-and-compare algorithm to detect abnormally low bids in procurement auctions
3noDetecting abnormally low bids in procurement auctions is a recognized problem, since their acceptance
could result in the winner not being able to provide the service or work awarded by the auction, which is
a significant risk for the auctioneer. A rank-and-compare algorithm is considered to detect such anomalous
bids and help auctioneers in achieving an effective rejection decision. Analytical expressions and
simulation results are provided for the detection probability, as well as for the false alarm probability.
The suggested range of application of the detection algorithm leaves out the cases of many tenderers
(more than 20) and quite dispersed bids (coefficient of variation larger than 0.15). An increase in the
number of tenderers leads to contrasting effects, since both the false alarm probability and the detection
probability are reduced. If the bids are spread over a large range, we have instead a double negative effect,
with more false alarms and less detections. The presence of multiple anomalous bids worsens the performance
of the algorithm as well. On the other hand, the method is quite robust to the presence of courtesy
bids.reservedmixedL. De Giovanni; P. L. Conti; M. NaldiDE GIOVANNI, Livia; P. L., Conti; M., Nald
Related and unrelated industry variety and the internationalization of start-ups
We study the relationship between industry variety in a start-up's home location and the start-up's internationalization in terms of both the likelihood of and persistence in exporting. Using a unique sample of Swedish start-ups, we find that related industry variety is positively associated with exporting likelihood and persistence, whereas unrelated industry variety is positively associated with exporting likelihood and persistence when the start-ups’ employees possess technological knowledge. We also find that employees’ international experience strengthens the positive relationship between related industry variety and start-ups’ export persistence. We provide auxiliary evidence of the proposed mechanisms through which related and unrelated industry variety affects start-ups’ internationalization—that is, through their effects on start-ups’ ability to launch novel products in foreign markets. The findings of our study provide policymakers preliminary evidence on th
Related and unrelated industry variety and the internationalization of start-ups
We study the relationship between industry variety in a start-up's home location and the start-up's internationalization in terms of both the likelihood of and persistence in exporting. Using a unique sample of Swedish start-ups, we find that related industry variety is positively associated with exporting likelihood and persistence, whereas unrelated industry variety is positively associated with exporting likelihood and persistence when the start-ups’ employees possess technological knowledge. We also find that employees’ international experience strengthens the positive relationship between related industry variety and start-ups’ export persistence. We provide auxiliary evidence of the proposed mechanisms through which related and unrelated industry variety affects start-ups
New radio observations of anomalous microwave emission in the HII region RCW175
We have observed the HII region RCW175 with the 64m Parkes telescope at
8.4GHz and 13.5GHz in total intensity, and at 21.5GHz in both total intensity
and polarization. High angular resolution, high sensitivity, and polarization
capability enable us to perform a detailed study of the different constituents
of the HII region. For the first time, we resolve three distinct regions at
microwave frequencies, two of which are part of the same annular diffuse
structure. Our observations enable us to confirm the presence of anomalous
microwave emission (AME) from RCW175. Fitting the integrated flux density
across the entire region with the currently available spinning dust models,
using physically motivated assumptions, indicates the presence of at least two
spinning dust components: a warm component with a relatively large hydrogen
number density n_H=26.3/cm^3 and a cold component with a hydrogen number
density of n_H=150/cm^3. The present study is an example highlighting the
potential of using high angular-resolution microwave data to break model
parameter degeneracies. Thanks to our spectral coverage and angular resolution,
we have been able to derive one of the first AME maps, at 13.5GHz, showing
clear evidence that the bulk of the AME arises in particular from one of the
source components, with some additional contribution from the diffuse
structure. A cross-correlation analysis with thermal dust emission has shown a
high degree of correlation with one of the regions within RCW175. In the center
of RCW175, we find an average polarized emission at 21.5GHz of
2.2\pm0.2(rand.)\pm0.3(sys.)% of the total emission, where we have included
both systematic and statistical uncertainties at 68% CL. This polarized
emission could be due to sub-dominant synchrotron emission from the region and
is thus consistent with very faint or non-polarized emission associated with
AME.Comment: Accepted for publication in the Astrophysical Journa
- …