6,978 research outputs found
Subjective Truths
__Abstract__
On the one hand, economists heavily rely on hard numbers: GDP, growth rate, and exchange rates. On the other hand, their explanations often rely on soft factors: executive confidence in the economy, consumer sentiment, and investor expectations. The hard numbers are objective, but the soft factors are subjective and depend on each individual. Economists increasingly recognize the need to study subjective factors.
The first part of the lecture illustrates the key role of subjective truths in modern economics. For instance, measures of subjective well-being are now being proposed to replace or at least complement GDP. Economic policies often rely on subjective forecasting by experts. The second part of the lecture will show that even though they are subjective, the soft factors can still be studied objectively. We will see how to incentivize people to reveal their expectations about future events but also their confidence in their expectations. Finally, I will show how to make people reveal truths that are completely unverifiable
Bayesian markets to elicit private information
Financial markets reveal what investors think about the future, and prediction markets are used to forecast election results. Could markets also encourage people to reveal private information, such as subjective judgments (e.g., âAre you satisfied with your life?â) or unverifiable facts? This paper shows how to design such markets, called Bayesian markets. People trade an asset whose value represents the proportion of affirmative answers to a question. Their trading position then reveals their own answer to the question. The results of this paper are based on a Bayesian setup in which people use their private information (their âtypeâ) as a signal. Hence, beliefs about othersâ types are correlated with oneâs own type. Bayes
Microlensing Surveys of M31 in the Wide Field Imaging Era
The Andromeda Galaxy (M31) is the closest large galaxy to the Milky Way, thus
it is an important laboratory for studying massive dark objects in galactic
halos (MACHOs) by gravitational microlensing. Such studies strongly complement
the studies of the Milky Way halo using the the Large and Small Magellanic
Clouds. We consider the possibilities for microlensing surveys of M31 using the
next generation of wide field imaging telescopes with fields of view in the
square degree range. We consider proposals for such imagers both on the ground
and in space. For concreteness, we specialize to the SNAP proposal for a space
telescope and the LSST proposal for a ground based telescope. We find that a
modest space-based survey of 50 visits of one hour each is considerably better
than current ground based surveys covering 5 years. Crucially, systematic
effects can be considerably better controlled with a space telescope because of
both the infrared sensitivity and the angular resolution. To be competitive, 8
meter class wide-field ground based imagers must take exposures of several
hundred seconds with several day cadence.Comment: 10 pages, 4 figures, 2 table
Optimal Microlensing Observations
One of the major limitations of microlensing observations toward the Large
Magellanic Cloud (LMC) is the low rate of event detection. What can be done to
improve this rate? Is it better to invest telescope time in more frequent
observations of the inner high surface-brightness fields, or in covering new,
less populated outer fields? How would a factor 2 improvement in CCD
sensitivity affect the detection efficiency? Would a series of major (factor
2--4) upgrades in telescope aperture, seeing, sky brightness, camera size, and
detector efficiency increase the event rate by a huge factor, or only
marginally? I develop a simplified framework to address these questions. With
observational resources fixed at the level of the MACHO and EROS experiments,
the biggest improvement (factor ~2) would come by reducing the time spent on
the inner ~25 deg^2 and applying it to the outer ~100 deg^2. By combining this
change with the characteristics of a good medium-size telescope (2.5 m mirror,
1" point spread function, thinned CCD chips, 1 deg^2 camera, and dark sky), it
should be possible to increase the detection of LMC events to more than 100 per
year (assuming current estimates of the optical depth apply to the entire LMC).Comment: Submitted to ApJ, 13 pages plus 3 figure
Search for supersymmetry in pp collisions at 7 TeV in events with jets and missing transverse energy
Acknowledge support from:
FMSR (Austria); FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ,
and FAPESP (Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC
(China); COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus);
Academy of Sciences and NICPB (Estonia); Academy of Finland,
ME, and HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG,
and HGF (Germany); GSRT (Greece); OTKA and NKTH (Hungary);
DAE and DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF
and WCU (Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and
UASLP-FAI (Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal);
JINR (Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST
and MAE (Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss
Funding Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK
(Turkey); STFC (United Kingdom); DOE and NSF (USA).A search for supersymmetry with R-parity conservation in protonâproton collisions at a centre-of-mass
energy of 7 TeV is presented. The data correspond to an integrated luminosity of 35 pbâ1 collected by
the CMS experiment at the LHC. The search is performed in events with jets and significant missing
transverse energy, characteristic of the decays of heavy, pair-produced squarks and gluinos. The primary
background, from standard model multijet production, is reduced by several orders of magnitude to a
negligible level by the application of a set of robust kinematic requirements. With this selection, the
data are consistent with the standard model backgrounds, namely tÂŻt, W + jet and Z + jet production,
which are estimated from data control samples. Limits are set on the parameters of the constrained
minimal supersymmetric extension of the standard model. These limits extend those set previously by
experiments at the Tevatron and LEP colliders.23 pĂĄginas, 5 figuras, 2 tablas.-- Open access:
This article is distributed under the terms of the Creative Commons Attribution
License 3.0.-- CMS Collaboration: et al.Peer reviewe
Measurement of WÎł and ZÎł production in pp collisions at âs = 7 TeV
21 pĂĄginas, 7 figuras, 2 tablas.-- Open access:
This article is distributed under the terms of the Creative Commons Attribution
License 3.0.-- CMS collaboration: et al.A measurement of WÎł and ZÎł production in protonâproton collisions at âs = 7 TeV is presented. Results
are based on a data sample recorded by the CMS experiment at the LHC, corresponding to an
integrated luminosity of 36 pbâ1. The electron and muon decay channels of the W and Z are used. The
total cross sections are measured for photon transverse energy EÎł
T > 10 GeV and spatial separation from
charged leptons in the plane of pseudorapidity and azimuthal angle R( ,Îł) > 0.7, and with an additional
dilepton invariant mass requirement of M > 50 GeV for the ZÎł process. The following cross
section times branching fraction values are found: Ï(ppâWÎł + X) Ă B(Wâ Îœ) = 56.3 ± 5.0(stat.) ± 5.0(syst.)±2.3(lumi.) pb and Ï(ppâZÎł + X)ĂB(Zâ ) = 9.4±1.0(stat.)±0.6(syst.)±0.4(lumi.) pb.
These measurements are in agreement with standard model predictions. The first limits on anomalous
WWÎł , ZZÎł , and Zγγ trilinear gauge couplings at âs =7 TeV are set.Acknowledge support from: FMSR (Austria);
FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP
(Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China);
COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); Academy
of Sciences and NICPB (Estonia); Academy of Finland, ME, and
HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF
(Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and
DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU
(Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI
(Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR
(Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE
(Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss Funding
Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey);
STFC (United Kingdom); DOE and NSF (USA).Peer reviewe
Searching for the reference point
Although reference dependence plays a central role in explaining behavior, little is known about the way that reference points are selected. This paper identifies empirically which reference point people use in decision under risk. We assume a comprehensive reference-dependent model that nests the main reference-dependent theories, including prospect theory, and that allows for isolating the reference point rule from other behavioral parameters. Our experiment involved high stakes with payoffs up to a week's salary. We used an optimal design to select the choices in the experiment and Bayesian hierarchical modeling for estimation. The most common reference points were the status quo and a security level (the maximum of the minimal outcomes of the prospects in a choice). We found little support for the use of expectations-based reference points
Search for a W boson decaying to a muon and a neutrino in pp collisions at âs = 7 TeV
20 pĂĄginas, 4 figuras, 3 tablas.-- Open access:
This article is distributed under the terms of the Creative Commons Attribution
License 3.0.-- CMS Collaboration: et al.A new heavy gauge boson, W', decaying to a muon and a neutrino, is searched for in pp collisions at a
centre-of-mass energy of 7 TeV. The data, collected with the CMS detector at the LHC, correspond to an
integrated luminosity of 36 pbâ1. No significant excess of events above the standard model expectation
is found in the transverse mass distribution of the muonâneutrino system. Masses below 1.40 TeV are
excluded at the 95% confidence level for a sequential standard-model-like W'. The W' mass lower limit
increases to 1.58 TeV when the present analysis is combined with the CMS result for the electron channel.Acknowledge support from: FMSR (Austria);
FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP
(Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China); COLCIENCIAS
(Colombia); MSES (Croatia); RPF (Cyprus); Academy of
Sciences and NICPB (Estonia); Academy of Finland, ME, and HIP
(Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF
(Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and
DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU
(Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI
(Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR
(Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE
(Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss Funding
Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey);
STFC (United Kingdom); DOE and NSF (USA).Peer reviewe
First measurement of the cross section for top-quark pair production in protonâproton collisions at âs = 7 TeV
20 pĂĄginas, 3 figuras, 1 tabla.-- This article is published Open Access at sciencedirect.com. It
is distributed under the terms of the Creative Commons Attribution
License 3.0.-- CMS Collaboration: et al.The first measurement of the cross section for top-quark pair production in pp collisions at the
Large Hadron Collider at center-of-mass energy âs = 7 TeV has been performed using a data sample
corresponding to an integrated luminosity of 3.1 ± 0.3 pbâ1 recorded by the CMS detector. This result
utilizes the final state with two isolated, highly energetic charged leptons, large missing transverse
energy, and two or more jets. Backgrounds from DrellâYan and non-W/Z boson production are estimated
from data. Eleven events are observed in the data with 2.1 ± 1.0 events expected from background. The
measured cross section is 194±72(stat.)±24(syst.)±21(lumi.) pb, consistent with next-to-leading order
predictions.Acknowledge support from: FMSR (Austria);
FNRS and FWO (Belgium); CNPq, CAPES, FAPERJ, and FAPESP
(Brazil); MES (Bulgaria); CERN; CAS, MoST, and NSFC (China);
COLCIENCIAS (Colombia); MSES (Croatia); RPF (Cyprus); Academy
of Sciences and NICPB (Estonia); Academy of Finland, ME, and
HIP (Finland); CEA and CNRS/IN2P3 (France); BMBF, DFG, and HGF
(Germany); GSRT (Greece); OTKA and NKTH (Hungary); DAE and
DST (India); IPM (Iran); SFI (Ireland); INFN (Italy); NRF and WCU
(Korea); LAS (Lithuania); CINVESTAV, CONACYT, SEP, and UASLPFAI
(Mexico); PAEC (Pakistan); SCSR (Poland); FCT (Portugal); JINR
(Armenia, Belarus, Georgia, Ukraine, Uzbekistan); MST and MAE
(Russia); MSTD (Serbia); MICINN and CPAN (Spain); Swiss Funding
Agencies (Switzerland); NSC (Taipei); TUBITAK and TAEK (Turkey);
STFC (United Kingdom); DOE and NSF (USA).Peer reviewe
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