Selfish Mining and Dyck Words in Bitcoin and Ethereum Networks

The main goal of this article is to present a direct approach for the formula giving the long-term apparent hashrates of Selfish Mining strategies using only elementary probabilities and combinatorics, more precisely, Dyck words. We can avoid computing stationary probabilities on Markov chain, nor stopping times for Poisson processes as in previous analysis. We do apply these techniques to other bockwithholding strategies in Bitcoin, and then, we consider also selfish mining in Ethereum

Agent-Based Simulations of Blockchain protocols illustrated via Kadena's Chainweb

While many distributed consensus protocols provide robust liveness and consistency guarantees under the presence of malicious actors, quantitative estimates of how economic incentives affect security are few and far between. In this paper, we describe a system for simulating how adversarial agents, both economically rational and Byzantine, interact with a blockchain protocol. This system provides statistical estimates for the economic difficulty of an attack and how the presence of certain actors influences protocol-level statistics, such as the expected time to regain liveness. This simulation system is influenced by the design of algorithmic trading and reinforcement learning systems that use explicit modeling of an agent's reward mechanism to evaluate and optimize a fully autonomous agent. We implement and apply this simulation framework to Kadena's Chainweb, a parallelized Proof-of-Work system, that contains complexity in how miner incentive compliance affects security and censorship resistance. We provide the first formal description of Chainweb that is in the literature and use this formal description to motivate our simulation design. Our simulation results include a phase transition in block height growth rate as a function of shard connectivity and empirical evidence that censorship in Chainweb is too costly for rational miners to engage in. We conclude with an outlook on how simulation can guide and optimize protocol development in a variety of contexts, including Proof-of-Stake parameter optimization and peer-to-peer networking design.Comment: 10 pages, 7 figures, accepted to the IEEE S&B 2019 conferenc

The taxation of discrete investment choices

Traditional analysis of the taxation of income from capital has focused on the impact of tax on marginal investment decisions; the principal impact of tax on investment is through the cost of capital, and is generally measured by an effective marginal tax rate. In this paper, we consider cases in which investors face a choice between two or more mutually exclusive projects, both of which are expected to earn at least the minimum required rate of return. Examples include the location decisions of multinationals, firms' choice of technology, and the choice of investment projects in the presence of binding financial constraints. In these cases the choice depends on the effective average tax rate. We propose a measure of this rate and demonstrate its relationship to the conventional effective marginal tax rate. Estimates of both are presented and compared for domestic and international investment in Germany, Japan, the UK and USA between 1979 and 1997

Taxing the Informal Economy: The Current State of Knowledge and Agendas for Future Research

This paper reviews the literature on taxation of the informal economy, taking stock of key debates and drawing attention to recent innovations. Conventionally, the debate on whether to tax has frequently focused on the limited revenue potential, high cost of collection, and potentially adverse impact on small firms. Recent arguments have increasingly emphasised the more indirect benefits of informal taxation in relation to economic growth, broader tax compliance, and governance. More research is needed, we argue, into the relevant costs and benefits for all, including quasi-voluntary compliance, political and administrative incentives for reform, and citizen-state bargaining over taxation

The taxation of discrete investment choices

Traditional analysis of the taxation of income from capital has focused on the impact of tax on marginal investment decisions; the principal impact of tax on investment is through the cost of capital, and is generally measured by an effective marginal tax rate. In this paper, we consider cases in which investors face a choice between two or more mutually exclusive projects, both of which are expected to earn at least the minimum required rate of return. Examples include the location decisions of multinationals, firms’ choice of technology, and the choice of investment projects in the presence of binding financial constraints. In these cases the choice depends on the effective average tax rate. We propose a measure of this rate and demonstrate its relationship to the conventional effective marginal tax rate. Estimates of both are presented and compared for domestic and international investment in Germany, Japan, the UK and USA between 1979 and 1997.