This thesis studies the effect of unstable leaders in Paxos protocol. Paxos algorithm is one of the most popular solutions for distributed consensus, and is often used for building replicated state machines. Safety is guaranteed by Paxos algorithm regardless of various machine and communication failures. However, the liveness is compromised when multiple Paxos leaders exist at the same time. Al...

A Web portal is a site that aggregates information from multiple sources on the World Wide Web and organizes this material in an easy user-friendly manner. Portals usually consist of a search engine, e-mail, news, and interactive chat facilities. The two main types of portals are horizontal and vertical portals. A horizontal portal is a Web site that provides consumers access to a number of dif...

This paper proves, in very general settings, that convex risk minimization is a procedure to select a unique conditional probability model determined by the classification problem. Unlike most previous work, we give results that are general enough to include cases in which no minimum exists, as occurs typically, for instance, with standard boosting algorithms. Concretely, we first show that any...

Empirical evidence shows that entrepreneurs hold a large fraction of wealth, have higher saving rates than workers, and face substantial uninsurable entrepreneurial and investment risks. This paper constructs a heterogeneous-agent general equilibrium model with uninsurable entrepreneurial risk and capital-market imperfections to explore the implications of uninsurable entrepreneurial risk for w...

Let (X ,μ) be a probability space, set X to be distributed according to μ and put Y to be an unknown target random variable. In the usual setup in learning theory, one observes N independent couples (Xi, Yi)Ni=1 in X × R, distributed according to the joint distribution of X and Y . The goal is to construct a real-valued function f which is a good guess/prediction of Y . A standard way of measur...

BACKGROUND Building highly qualified General Practitioners (GPs) is key to the development of primary health care. It's therefore urgent to ensure the GPs' quality service under the background of the new round of health care system reforms in China. A new model of GP qualification examination was originally implemented in Pudong New Area of Shanghai, China, which aimed to empirically evaluate t...

Gaze tracking is the technology that identifies a region in space that a user is looking at. Most previous non-wearable gaze tracking systems use a near-infrared (NIR) light camera with an NIR illuminator. Based on the kind of camera lens used, the viewing angle and depth-of-field (DOF) of a gaze tracking camera can be different, which affects the performance of the gaze tracking system. Nevert...