728 research outputs found
All-pay auctions with resale
We study equilibria of first- and second-price all-pay auctions with resale when playersâ signals are affiliated and symmetrically distributed. We show that existence of resale possibilities introduces an endogenous element to playersâ valuations and creates a signaling incentive for players. We characterize symmetric bidding equilibria for both firstand second-price all-pay auctions with resale and provide sufficient conditions for existence of symmetric equilibria. Under our conditions we show that second-price all-pay auctions generate no less expected revenue than first-price all-pay auctions with resale. The initial seller could benefit from publicly disclosing his private information which is affiliated with playersâ signals.all-pay auction, resale
A study of the high-inclination population in the Kuiper belt - II. The Twotinos
As the second part of our study, in this paper we proceed to explore the
dynamics of the high-inclination Twotinos in the 1:2 Neptune mean motion
resonance (NMMR). Depending on the inclination , we show the existence of
two critical eccentricities and , which are lower limits of
the eccentricity for the resonant angle to exhibit libration and
asymmetric libration, respectively. Accordingly, we have determined the
libration centres for inclined orbits, which are strongly dependent
on . With initial on a fine grid of , the
stability of orbits in the 1:2 NMMR is probed by 4-Gyr integrations. It is
shown that symmetric librators are totally unstable for ; while
stable asymmetric librators exist for up to .
We further investigate the 1:2 NMMR capture and retention of planetesimals
with initial inclinations in the planet migration model
using a time-scale of yr. We find that: (1) the capture
efficiency of the 1:2 NMMR decreases drastically with the increase of ,
and it goes to 0 when ; (2) the probability of discovering
Twotinos with , beyond observed values, is roughly estimated to
be per cent; (3) more particles are captured into the leading rather
than the trailing asymmetric resonance for , but this number
difference appears to be the opposite at and is continuously
varying for even larger ; (4) captured Twotinos residing in the trailing
resonance or having are practically outside the Kozai mechanism,
like currently observed samples.Comment: 13 pages, 10 figures, Accepted by MNRAS. Comments welcome
Formation and transformation of the 3:1 mean-motion resonance in 55 Cancri System
We report in this paper the numerical simulations of the capture into the 3:1
mean-motion resonance between the planet b and c in the 55 Cancri system. The
results show that this resonance can be obtained by a differential planetary
migration. The moderate initial eccentricities, relatively slower migration and
suitable eccentricity damping rate increase significantly the probability of
being trapped in this resonance. Otherwise, the system crosses the 3:1
commensurability avoiding resonance capture, to be eventually captured into a
2:1 resonance or some other higher-order resonances. After the resonance
capture, the system could jump from one orbital configuration to another one if
the migration continues, making a large region of the configuration space
accessible for a resonance system. These investigations help us understand the
diversity of resonance configurations and put some constrains on the early
dynamical evolution of orbits in the extra-solar planetary systems.Comment: 6 pages with 2 figures. Submitted for publication in the proceedings
of IAU Symposium No.249. A paper telling much more details than this paper is
under preparin
THREE ESSAYS ON AUCTION THEORY AND CONTEST THEORY
In the first chapter, ¥°All-Pay Auctions with Resale¥±, I study equilibria of first- and second-price all-pay auctions with resale when players' signals are affiliated and symmetrically distributed. I show that existence of resale possibilities introduces an endogenous element to players' valuations and creates a signaling incentive for players. I characterize symmetric bidding equilibria for both first- and second-price all-pay auctions with resale and provide sufficient conditions for existence of symmetric equilibria. Under those conditions I show that second-price all-pay auctions generate no less expected revenue than first-price all-pay auctions with resale. The initial seller could benefit from publicly disclosing her private information which is affiliated with players' signals.Outcome in all-pay auctions is deterministic since the highest bidder wins the prize with probability one. However, many realistic contests have in-deterministic outcome and no player can guarantee winning the prize. The second chapter, ¥°Rent-Seeking Contest with Private Values and Resale¥±, studies rent-seeking contests with private values and resale possibilities. With an in-deterministic success function, the resulting possible inefficiency creates a motive for aftermarket trade. Players' valuations are endogenously determined when there is an opportunity of resale. I characterize symmetric equilibria. I assume that the winner has full bargaining power; however, the results extend to other resale mechanisms. I show that resale enhances allocative efficiency ex post at the expense of more wasted social resources since players compete more aggressively with resale possibilities.In the third chapter, ¥°The Imperfectly Discriminating Contests with Incomplete Information¥±, I study the existence of monotone pure-strategy equilibria in imperfectly discriminating contests with incomplete information. Sufficient conditions under which equilibria exist are provided for both finite-action and continuum-action cases. Using a two-bidder example, we derive some properties of equilibria and show a special case of revenue equivalence between contests with incomplete information and contests with complete information
Rent seeking contests with private values and resale
Abstract This paper studies rent-seeking contests with private values and resale possibilities. With a stochastic success function, the resulting possible inefficiency creates a motive for aftermarket trade. Players' valuations are endogenously determined when there is an opportunity of resale. We characterize symmetric equilibria. We assume that the winner has full bargaining power, however, the results extend to other resale mechanisms. We show that resale enhances allocative efficiency ex post at the expense of more wasted social resources since players compete more aggressively with resale possibilities
All-pay auctions with resale
We study equilibria of first- and second-price all-pay auctions with resale when playersâ signals are affiliated and symmetrically distributed. We show that existence of resale possibilities introduces an endogenous element to playersâ valuations and creates a signaling incentive for players. We characterize symmetric bidding equilibria for both firstand second-price all-pay auctions with resale and provide sufficient conditions for existence of symmetric equilibria. Under our conditions we show that second-price all-pay auctions generate no less expected revenue than first-price all-pay auctions with resale. The initial seller could benefit from publicly disclosing his private information which is affiliated with playersâ signals
All-pay auctions with resale
We study equilibria of first- and second-price all-pay auctions with resale when playersâ signals are affiliated and symmetrically distributed. We show that existence of resale possibilities introduces an endogenous element to playersâ valuations and creates a signaling incentive for players. We characterize symmetric bidding equilibria for both firstand second-price all-pay auctions with resale and provide sufficient conditions for existence of symmetric equilibria. Under our conditions we show that second-price all-pay auctions generate no less expected revenue than first-price all-pay auctions with resale. The initial seller could benefit from publicly disclosing his private information which is affiliated with playersâ signals
Religiosity and Risky Sexual Behavior Among Adolescents in Sarawak, Malaysia
Introduction: Risky sexual behavior is defined as a behavior that increases oneâs risk of contracting or being
infected by sexually transmitted infections (STIs) and experiencing unintended pregnancies. This study examined
the relationship between religiosity and risky sexual behavior among adolescents in the state of Sarawak,
Malaysia.
Methods: The inclusion criteria included 1,146 unmarried adolescents aged between 16 and 19 years, whereby
they answered a validated self-administered questionnaire using the modified Religion Scale and Risky Sexual
Behavior â Unsafe Sex Scale. The analysis was restricted to respondents who reported to have had sex.
Results: Overall, the response rate recorded 95% (n=1,086), whereby the prevalence of respondents who reported
that they have had sex was 9.5%, n=103 (71 males, 32 females, mean age 17.82). Descriptive results further
showed that the prevalence of those who have had sex for male and female were 6.53% and 2.94%, respectively.
The earliest sexual debut was revealed to be at 13 years of age. Moreover, bivariate analyses indicated a significant
and negative correlation between religious practice and risky sexual behavior (r= -.23; p<.05).
Conclusion: The study revealed that religious adolescents are more likely to avoid risky sexual behavior. This
means that religious practice may become a potential protective factor in influencing adolescents to avoid risky
sexual behaviors. (Abstract by authors
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