ABSTRACT
This chapter provides the techniques for estimating a regression equation, the standard error, and the coefficients of determination and correlation. It explains the purpose of regression and correlation analysis in agricultural and environmental research. The chapter evaluates the regression equation and the standard error of estimate. It utilizes the computed equation to prepare interval estimates, and makes predictions for forecasting purposes. The chapter computes a measure of the strength of the correlation between two variables (coefficients of determination and correlation). It provides tests of hypothesis about the relationship of the two variables. The chapter presents the assumptions of linear regression analysis, and point out pitfalls in using the regression and correlation techniques. The standard error of estimate is used as a measure of scatter or dispersion of the points about the regression line, just as one uses the standard deviation to measure the deviation of the individual observations about the mean of those values.
