Visuals and graphics have been used for communicating complex ideas since 1786 when William Playfair first invented the line graph and bar chart. Graphs and charts are useful for interpretation and making sense of data. For instance, John Snow's scatter plot helped pinpoint the source of a cholera outbreak in London in 1854 and also changed…

Newer statistical procedures are typically introduced to help address the limitations of those already in practice or to deal with emerging research needs. Quantile regression (QR) is introduced in this paper as a relatively new methodology, which is intended to overcome some of the limitations of least squares mean regression (LMR). QR is more…

Several statistical techniques that can be used to ameliorate the difficulties inherent in the data analysis of longitudinal studies are presented. The first step in longitudinal data analysis is graphing. This permits visual inspection of the data, and with educated viewing can yield insights into the nature of the underlying mechanisms. The next…

THIS ARTICLE PRESENTS SIZE AND GROWTH VELOCITY DATA COLLECTED DURING A LONGITUDINAL STUDY OF 111 NORMAL, HEALTHY NEGRO INFANTS FROM LOWER-MIDDLE-CLASS FAMILIES. DATA WERE OBTAINED FROM BIRTH RECORDS AND MEASUREMENTS TAKEN DURING ROUTINE PHYSICAL EXAMINATIONS. WHEN THIS NEGRO SAMPLE WAS COMPARED WITH WHITE INFANTS IN SIMILAR STUDIES IT WAS FOUND…

This research discusses the relationship between the migration of skilled professional and managerial workers from Canada to the United States, the so called "brain drain," and seeks to determine if and how the Canada-U.S. Free Trade Agreement (F.T.A.) and the North American Free Trade Agreement (NAFTA) may have affected bilateral flows…