Bitcoin networkThe Bitcoin network is a peer-to-peer network of nodes which implement the Bitcoin protocol. The protocol itself implements a highly available, public, and decentralized ledger. The nodes verify that each update to the ledger follows the rules of the Bitcoin protocol. Users broadcast cryptographically signed messages to the network using Bitcoin cryptocurrency wallet software. These messages are proposed transactions, changes to be made in the ledger. Each node has a copy of the ledger's entire transaction history.
Robust statisticsRobust statistics are statistics with good performance for data drawn from a wide range of probability distributions, especially for distributions that are not normal. Robust statistical methods have been developed for many common problems, such as estimating location, scale, and regression parameters. One motivation is to produce statistical methods that are not unduly affected by outliers. Another motivation is to provide methods with good performance when there are small departures from a parametric distribution.
Linear regressionIn statistics, linear regression is a linear approach for modelling the relationship between a scalar response and one or more explanatory variables (also known as dependent and independent variables). The case of one explanatory variable is called simple linear regression; for more than one, the process is called multiple linear regression. This term is distinct from multivariate linear regression, where multiple correlated dependent variables are predicted, rather than a single scalar variable.
Payment systemA payment system is any system used to settle financial transactions through the transfer of monetary value. This includes the institutions, payment instruments such as payment cards, people, rules, procedures, standards, and technologies that make its exchange possible. A common type of payment system, called an operational network, links bank accounts and provides for monetary exchange using bank deposits. Some payment systems also include credit mechanisms, which are essentially a different aspect of payment.