This simulation illustrates least squares regression and how the least squares solution minimizes the sum of the squared residuals. The applet demonstrates, in a visual manner, various concepts related to least squares regression. These include residuals, sum of squares, the mean line, how the line of best fit is determined, and how the line of least squares solution minimizes the sum of the squared residuals.
This site is a collection of resources related to experiments. The site includes references, resources, and articles related to the scientific method, experimental research, ethics in research, and research design. It also includes tips on writing scientific papers, and there are several statistics tutorials on the site. Another interesting feature of the site is a collection of case studies that include descriptions of famous research studies in fields like social psychology, sociology, physics, biology, and medicine.