Correlation and Regression Evaluate overall pattern: form, strength, direction Least-squares regression line: = 0 + 1 Residual: observed - predicted = The conditions to perform regression: The samples are random Data is linear Variance is constant Standard error of 1 is found using computer output. Test statistic for 0:1 = 0: = 1 0 1 = 2 what do all of the signs and letters stand for or represent