why are correlation coefficients used in a co-variance matrix? how to do a correlation test on a matrix can a weighted average get out of range what is the difference between a ga and a negative weight combining correlated measurements with uncorrelated error is how to calculate weighted average what is the correlation coefficient for a covariance matrix? how to find correlation coefficient of a correlation matrix can you measure the same thing two different way when are paired pairs correlated? combining correlated measurements what are correlation coefficients used for what is the correct way to measure a statistic why are the systematic errors larger? how to find out if a weighted average is uncorrelated? when to find the correlation coefficient in rho can i combine a gaussian error and a negative value from an opps matrix why are gaussian errors a negative measure how to find if a measure is in the same range as another why does the matrix of a weighted average have a negative correlation coefficient?