4,086 research outputs found
Bayesian adaptation
In the need for low assumption inferential methods in infinite-dimensional
settings, Bayesian adaptive estimation via a prior distribution that does not
depend on the regularity of the function to be estimated nor on the sample size
is valuable. We elucidate relationships among the main approaches followed to
design priors for minimax-optimal rate-adaptive estimation meanwhile shedding
light on the underlying ideas.Comment: 20 pages, Propositions 3 and 5 adde
The ISO 170um Luminosity Function of Galaxies
We constructed a local luminosity function (LF) of galaxies using a
flux-limited sample (S_170 > 0.195Jy) of 55 galaxies at z < 0.3 taken from the
ISO FIRBACK survey at 170um. The overall shape of the 170-um LF is found to be
different from that of the total 60-um LF (Takeuchi et al. 2003): the bright
end of the LF declines more steeply than that of the 60-um LF. This behavior is
quantitatively similar to the LF of the cool subsample of the IRAS PSCz
galaxies. We also estimated the strength of the evolution of the LF by assuming
the pure luminosity evolution (PLE): L(z) \propto (1+z)^Q. We obtained
Q=5.0^{+2.5}_{-0.5} which is similar to the value obtained by recent Spitzer
observations, in spite of the limited sample size. Then, integrating over the
170-um LF, we obtained the local luminosity density at 170um, \rho_L(170um). A
direct integration of the LF gives \rho_L(170um) = 1.1 \times 10^8 h Lsun
Mpc^{-3}, whilst if we assume a strong PLE with Q=5, the value is 5.2 \times
10^7 h Lsun Mpc^{-3}. This is a considerable contribution to the local FIR
luminosity density. By summing up with other available infrared data, we
obtained the total dust luminosity density in the Local Universe,
\rho_L(dust)=1.1 \times 10^8 h Lsun Mpc^{-3}. Using this value, we estimated
the cosmic star formation rate (SFR) density hidden by dust in the Local
Universe. We obtained \rho_SFR(dust) \simeq 1.1-1.2 h \times 10^{-2} Msun
yr^{-1} Mpc^{-3}$, which means that 58.5% of the star formation is obscured by
dust in the Local Universe.Comment: A&A in pres
Your Morals Are Your Moods
We test the effect of players' moods on their behavior in a gift-exchange game. In the first stage of the game, player 1 chooses a transfer to player 2. In the second stage, player 2 chooses an effort level. Higher effort is more costly for player 2, but it increases player 1's payoff. We say that player 2 reciprocates if effort is increasing in the transfer received. Player 2 is generous if an effort is incurred even when no transfer is received. Subjects play this game in two different moods. To induce a `bad mood', subjects in the role of player 2 watched a sad movie before playing the game; to induce a `good mood', they watched a funny movie. Mood induction was effective: subjects who saw the funny movie reported a significantly better mood than those who saw the sad movie. These two moods lead to significant differences in player 2's behavior. We find that a bad mood implies more reciprocity while a good mood implies more generosity. Since high transfers are relatively more common, player 1 makes more money when second movers are in a bad mood.
Far-Ultraviolet and Far-Infrared Bivariate Luminosity Function of Galaxies: Complex Relation between Stellar and Dust Emission
Far-ultraviolet (FUV) and far-infrared (FIR) luminosity functions (LFs) of
galaxies show a strong evolution from to , but the FIR LF
evolves much stronger than the FUV one. The FUV is dominantly radiated from
newly formed short-lived OB stars, while the FIR is emitted by dust grains
heated by the FUV radiation field. It is known that dust is always associated
with star formation activity. Thus, both FUV and FIR are tightly related to the
star formation in galaxies, but in a very complicated manner. In order to
disentangle the relation between FUV and FIR emissions, we estimate the UV-IR
bivariate LF (BLF) of galaxies with {\sl GALEX} and {\sl AKARI} All-Sky Survey
datasets. Recently we invented a new mathematical method to construct the BLF
with given marginals and prescribed correlation coefficient. This method makes
use of a tool from mathematical statistics, so called "copula". The copula
enables us to construct a bivariate distribution function from given marginal
distributions with prescribed correlation and/or dependence structure. With
this new formulation and FUV and FIR univariate LFs, we analyze various FUV and
FIR data with {\sl GALEX}, {\sl Spitzer}, and {\sl AKARI} to estimate the UV-IR
BLF. The obtained BLFs naturally explain the nonlinear complicated relation
between FUV and FIR emission from star-forming galaxies. Though the faint-end
of the BLF was not well constrained for high- samples, the estimated linear
correlation coefficient was found to be very high, and is remarkably
stable with redshifts (from 0.95 at to 0.85 at ). This implies
the evolution of the UV-IR BLF is mainly due to the different evolution of the
univariate LFs, and may not be controlled by the dependence structure.Comment: 10 pages, 7 figures, Earth, Planets and Space, in pres
Your Morals are Your Moods
We test the effect of players' moods on their behavior in a gift-exchange game.In the first stage of the game, player 1 chooses a transfer to player 2.In the second stage, player 2 chooses an effort level.Higher effort is more costly for player 2, but it increases player 1's payoff.We say that player 2 reciprocates if effort is increasing in the transfer received.Player 2 is generous if an effort is incurred even when no transfer is received.Subjects play this game in two different moods.To induce a `bad mood', subjects in the role of player 2 watched a sad movie before playing the game; to induce a `good mood', they watched a funny movie.Mood induction was effective: subjects who saw the funny movie reported a significantly better mood than those who saw the sad movie.These two moods lead to significant differences in player 2's behavior.We find that a bad mood implies more reciprocity while a good mood implies more generosity.Since high transfers are relatively more common, player 1 make more money when second movers are in a bad mood.rationality;motivation;game theory;emotions;reciprocity;gift giving
THE VALUE OF WATER AS AN URBAN CLUB GOOD: A MATCHING APPROACH TO HOA-PROVIDED LAKES
Urban lakes located in arid environments require large quantities of water to maintain their water levels, with much of this water associated with high opportunity costs. Many of these lakes are manmade and provide various amenities to surrounding residents. In this paper we use matching techniques to recover the average capitalized value of lakes to surrounding communities and differentiate between community members and adjacent households to recover heterogeneous treatment effects. Importantly, we consider the role of both unobservable and observable features of matching to recover heterogeneous capitalization across lake communities. Our results suggest that the capitalized value of lakes to community residents is highly heterogeneous and ranges from an annual value of -20 per homeowner per acre foot of water. These results suggest that small changes in water pricing could remove the surplus benefits of lakes to community residents.Matching, Treatment effects, Urban lakes, Capitalization, Environmental Economics and Policy, Political Economy, Resource /Energy Economics and Policy,
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