Taking a simplified approach to statistics, this textbook teaches students the skills required to conduct and understand quantitative research. It provides basic mathematical instruction without compromising on analytical rigor, covering the essentials of research design; descriptive statistics;...

Researchers in many fields, such as demography, economics, and sociology, have established various data collection methodologies and principles to answer a range of academic and policy questions on migration. Although the progress has been impressive, some basic challenges remain. This paper...

The aim of this paper is to introduce a practical nonlinear generalization of PCA that captures nonlinear forms of dependence and delivers truly independent factors. The output of the method is a low-dimensional curvilinear coordinate system that tracks the important features of the data. The...