what is the use of the second time point why do i use the second time point what is the mean of the 2nd time point? how to compute correlation of two observations if a time series is stationary and the variance is equal, how should i calculate the correlation? what is the correlation between a time series what point should you use to compute correlation when calculating correlation when to use second time point what is the second time point of the sample for the first set of observations? why use 2nd time point for the mean of a time series why not use the second time point for the mean how to use the second time point which time period is included in measuring correlation between samples of unequal size? what point of time should i use to compute correlation when do you compute the correlation how to calculate correlation between two samples how to figure correlation between time series and samples what points do you use to compute correlation when do you use the 2nd time point in the correlation of the two time series?