In this paper, we propose a framework to build prediction models from data streams which contain both labeled and unlabeled examples. We argue that due to the increasing data collection ability but limited resources for labeling, stream data collected at hand may only have a small number of...

The first essay uses a model of profit-maximizing hospitals to examine hospital responses to global budgeting in the forms of dumping and cost shifting. The main findings include: (1) Hospitals dump insured patients when the covered services are priced under costs. Whetherthe budget target is...

In this study, we employ a statistical arbitrage approach to demonstrate that momentum investment strategy tend to work better in periods longer than six months, a result different from findings in past literature. Compared with standard parametric tests, the statistical arbitrage method...

The first essay uses a model of profit-maximizing hospitals to examine hospital responses to global budgeting in the forms of dumping and cost shifting. The main findings include: (1) Hospitals dump insured patients when the covered services are priced under costs. Whetherthe budget target is...

Is a more heterogeneous population beneficial or harmful to long-term economic performance? This paper addresses this and other questions in a dynamic general equilibrium model where consumers have different labour productivity and time preference. We show how differences in the cross-sectional...

Is a more heterogeneous population conducive or detrimental to capital accumulation and economic growth? This paper addresses this question using a dynamic general equilibrium model with ex ante heterogeneous consumers and progressive taxation. We show that the answer depends crucially on the...

This paper examines the relation between diversity and long-term economic performance in a dynamic general equilibrium model where consumers differ ex ante in time preference and labour productivity. We show that changing the distribution of these characteristics will affect the steady state by...