In many learning settings, active/adaptive querying is possible, but the number of rounds of adaptivity is limited. We study the relationship between query complexity and adaptivity in identifying the k most biased coins among a set of n coins with unknown biases. This problem is a common abstraction of many well-studied problems, including the problem of identifying the k best arms in a stocha...

We construct a random matching model of a monetary economy with commodity money in the form of potentially different types of silver coins that are distinguishable by the quantity of metal they contain. The quantity of silver in the economy is assumed to be fixed, but agents can mint and melt coins. Coins yield no utility, but can be traded. Uncoined silver yields direct utility to the holder. ...

Analysing Roman coins found in archaeology sites has been traditionally done manually by an operator using volumetric image slices provided by a computed tomography scanner. In order to automate the counting process, a good segmentation for the coins has to be achieved to separate the touching surfaces of the coins. Separating touching surfaces in volumetric images has not yet attracted much at...

We present a bandwidth-efficient off-line anonymous e-cash scheme with traceable coins. Once a user double-spends, his identity can be revealed and all his coins in the system can be traced, without resorting to TTP. For a security level comparable with 1024-bit standard RSA signature, the payment transcript size is only 512 bytes. Security of the proposed scheme is proven under the q-strong Di...

Treasury bonds provide money-like services, while other bonds do not. These money-like services, which include safety and liquidity, are valued more during financial crises, reducing the substitutability of actual Treasuries and synthetic Treasuries—other types of bonds that yield the same cash flows. Large equilibrium yield spreads between actual and synthetic Treasuries result. During the rec...

Given a set of n coins, some of them weighing H, the others weighing h, h < H, we prove that to determine the set of heavy coins, an optimal algorithm requires an average of 1+ρ 1+ρ+ρ n + O(1) comparisons, using a beam balance, in which ρ denotes the ratio of the probabilities of being light and heavy. A simple quasi-optimal algorithm is described. Similar results are derived for the majority p...