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A common observation in the informal literature of economics (and elsewhere) is that in multistage "games," players may seek early in the game to acquire a reputation for being "tough" or "benevolent" or something else. But this phenomenon is not observed in some formal game-theoretic analyses of finite games, such as Selten's finitely repeated chain-store game or in the finitely repeated prisoners' dilemma. We reexamine Selten's model, adding to it a "small" amount of imperfect (or incomplete) information about players' payoffs, and we find that this addition is sufficient to give rise to the "reputation effect" that one intuitively expects. Journal of Economic Literature,

We summarize five years of continuous monitoring of accretion-powered pulsars with the Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray Observatory. Our 20-70 keV observations have determined or refined the orbital parameters of 13 binaries, discovered 5 new transient accreting pulsars, measured the pulsed flux history during outbursts of 12 transients (GRO J1744-28, 4U 0115+634, GRO J1750-27, GS 0834-430, 2S 1417-624, GRO J1948+32, EXO 2030+375, GRO J1008-57, A 0535+26, GRO J2058+42, 4U 1145-619 and A 1118-616), and also measured the accretion torque history of during outbursts of 6 of those transients whose orbital parameters were also known. We have also continuously measured the pulsed flux and spin frequency for eight persistently accreting pulsars (Her X-1, Cen X-3, Vela X-1, OAO 1657-415, GX 301-2, 4U 1626-67, 4U 1538-52, and GX 1+4). Because of their continuity and uniformity over a long baseline, BATSE observations have provided new insights into the long-term behavior of accreting magnetic stars. We have found that all accreting pulsars show stochastic variations in their spin frequencies and luminosities, including those displaying secular spin-up or spin-down on long time scales, blurring the conventional distinction between disk-fed and wind-fed binaries. Pulsed flux and accretion torque are strongly correlated in outbursts of transient accreting pulsars, but uncorrelated, or even anticorrelated, in persistent sources.Comment: LaTeX, psfig, 90 pages, 42 figures. To appear in Dec. 1997 ApJS, Vol 113, #

A common observation in experiments involving finite repetition of the prisoners' dilemma is that players do not always play the single-period dominant strategies ("finking"), but instead achieve some measure of cooperation. Yet finking at each stage is the only Nash equilibrium in the finitely repeated game. We show here how incomplete information about one or both players' options, motivation or behavior can explain the observed cooperation. Specifically, we provide a bound on the number of rounds at which Fink may be played, when one player may possibly be committed to a "Tit-for-Tat" strategy.

Sequential allocation is a simple mechanism for sharing multiple indivisible items. We study strategic behavior in sequential allocation. In particular, we consider Nash dynamics, as well as the computation and Pareto optimality of pure equilibria, and Stackelberg strategies. We first demonstrate that, even for two agents, better responses can cycle. We then present a linear-time algorithm that returns a profile (which we call the "bluff profile") that is in pure Nash equilibrium. Interestingly, the outcome of the bluff profile is the same as that of the truthful profile and the profile is in pure Nash equilibrium for all cardinal utilities consistent with the ordinal preferences. We show that the outcome of the bluff profile is Pareto optimal with respect to pairwise comparisons. In contrast, we show that an assignment may not be Pareto optimal with respect to pairwise comparisons even if it is a result of a preference profile that is in pure Nash equilibrium for all utilities consistent with ordinal preferences. Finally, we present a dynamic program to compute an optimal Stackelberg strategy for two agents, where the second agent has a constant number of distinct values for the items.

Observations have been made of a new terrestrial phenomenon: brief (-millisecond), intense flashes of gamma rays, observed with space-borne detectors. These flashes must originate at altitudes in the atmosphere above at least 30 km in order to be observable by orbiting detectors aboard the Compton Gamma-Ray Observatory (CGRO). At least a dozen events have been detected over the past 2 years. The photon spectra from the events are very hard and are consistent with bremsstrahlung emission from energetic (MeV) electrons. The most likely origin of these high energy electrons, while speculative at this time, is a rare type of high altitude electrical discharge above thunderstorm regions. 3 / 9 3 0064142https://ntrs.nasa.gov/search.jsp?R=19960001309 2018-05-11T01:44:02+00:00ZWe report here the serendipedous detection of high-energy photons from the Earth's upper atmosphere, observed by the Burst and Transient Source Experiment1 (BATSE) on the CGRO.Their apparent correlation with storm systems leads us to implicate as their cause, electrical discharges from these systems to the stratosphere/ionosphere. Runaway discharges to the ionosphere had been predicted in the early literaturG3 and modeled in detail pre~iously.~ These gamma-ray events may also be related to recently recorded optical discharge phenomena above thunderstorms5 and to other cloud-to-stratosphere discharges that have been reported in the past.6-7The Compton Observatory was launched in April 199 1 to perform observations of celestial gamma-ray sources. The BATSE experiment1 is one of four experiments on the observatory. It serves as an all-sky monitor and has detected over 800 cosmic gamma-ray bursts, several hard xray transients, numerous persistent and pulsed hard x-ray sources and several thousand solar flares. In addition to these celestial sources, on m occasions BATSE has responded to gammaray flashes from the Earth, previously unreported.BATSE consists of an array of eight detector modules located at the corners of the observatory, arranged to provide maximum unobstructed sky coverage. The scintillation detectors are sensitive to photons with energies above 20 keV. It is believed that prior instrumentation and experiments were incapable of detecting this phenomenon for several reasons, or these events were overlooked as being spurious. Most detectors used in high-energy astronomy are collimated and would likely have missed these rare events andor data are not analyzed during Earth-viewing times. Also, the temporal resolution of most experiments would not have been able to respond to these very brief events and would thus have had p r signal-to-noise when sampled with coarser time resolution. The BATSE array of multiple, independent detectors viewing different directions gives us confidence in the reality of these events as opposed to some instrumental or spacecraft effect such as electronic noise. The multiple, wide-field detectors also allow a direction determination to be made for each events The observed counting rate ratios of the detec...

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