Socially Optimal Mining Pools

Mining for Bitcoins is a high-risk high-reward activity. Miners, seeking to reduce their variance and earn steadier rewards, collaborate in pooling strategies where they jointly mine for Bitcoins. Whenever some pool participant is successful, the earned rewards are appropriately split among all pool participants. Currently a dozen of different pooling strategies (i.e., methods for distributing the rewards) are in use for Bitcoin mining. We here propose a formal model of utility and social welfare for Bitcoin mining (and analogous mining systems) based on the theory of discounted expected utility, and next study pooling strategies that maximize the social welfare of miners. Our main result shows that one of the pooling strategies actually employed in practice--the so-called geometric pay pool--achieves the optimal steady-state utility for miners when its parameters are set appropriately. Our results apply not only to Bitcoin mining pools, but any other form of pooled mining or crowdsourcing computations where the participants engage in repeated random trials towards a common goal, and where "partial" solutions can be efficiently verified

The Crucified Book, Textual Authority and the Gospel of Truth.

The Gospel of Truth depicts the crucified Jesus wrapped in a scroll, reading aloud the contents of his heart as he died. This is just one of many strange appearances by the physical book in the Gospel of Truth and the fragments of Valentinus. This dissertation argues that through its representations of the written word, the Gospel of Truth promoted a living document perspective on the holy book, encouraging the generation of religious books as new sources of revelatory authority. The text describes the existence of a divine spark (logos) within each member of humankind, endowing all with capacity to speak or write a version of the gospel. I place this Valentinian theory of open canon, and person-as-sacred-book within an empire-wide debate about books and their attendant authority. In Roman and Jewish texts we find similar efforts to equate holy person with holy text, while Christian heresiologists exhibit awareness of the living book through their fierce vituperations. Although the Gospel of Truth is often set apart from contemporary mainstream Christianity, its ideas about the nature of authoritative writing engaged with Greco-Roman culture and also cohered with Jewish and Christian ideas about books in antiquity. In particular, Valentinian views about the relationship between the oral and the written dovetailed with thinking on the nature of the sacred book that gradually became the trademark of Rabbinic Judaism. Ultimately, because the Gospel of Truth reflects a mind that was at the center of the discursive debates that formed Judaism and Christianity, this project demonstrates the usefulness of so-called heretical texts for discussions on the parting of the ways between the two traditions.PHDNear Eastern StudiesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/100046/1/akreps_1.pd

License prices for financially constrained firms

It is often alleged that high auction prices inhibit service deployment. We investigate this claim under the extreme case of financially constrained bidders. If demand is just slightly elastic, auctions maximize consumer surplus if consumer surplus is a convex function of quantity (a common assumption), or if consumer surplus is concave and the proportion of expenditure spent on deployment is greater than one over the elasticity of demand. The latter condition appears to be true for most of the large telecom auctions in the US and Europe. Thus, even if high auction prices inhibit service deployment, auctions appear to be optimal from the consumers’ point of view

Does timing of decisions in a mixed duopoly matter?

We determine the endogenous order of moves in a mixed pricesetting duopoly. In contrast to the existing literature on mixed oligopolies we establish the payo equivalence of the games with an exogenously given order of moves if the most plausible equilibrium is realized in the market. Hence, in this case it does not matter whether one becomes a leader or a follower. We also establish that replacing a private firm by a public firm in the standard Bertrand-Edgeworth game with capacity constraints increases social welfare and that a pure-strategy equilibrium always exists

Proceedings of the 2nd Workshop on Flavor Symmetries and Consequences in Accelerators and Cosmology (FLASY12)

These are the proceedings of the 2nd Workshop on Flavor Symmetries and Consequences in Accelerators and Cosmology, held 30 June 2012 - 4 July 2012, Dortmund, Germany.Comment: Order 400 pages, several figures including the group picture v2: corrected author list and contributio