which model does first-difference analysis depend on? what is the difference between a first-difference estimator, a column estimator or an OLS model? what's the difference between the pooled and the first-difference estimators? which ols estimator is more efficient which is stronger first-difference or pooled ols what is the first difference in a pooled ols analysis how do you calculate the average ols which two-period model would always be a first-difference how to estimate the ols for the first period why are first-difference estimators better than pooled ols what is the ols pool what is the value of delta_i in a first-difference estimator how to find the difference between pooled and first-difference models what is delta_i what is delta_i if i have a linear regression what is the value for a ols model when to use the ols first difference estimator what is pooled ols how to find the value for delta of a ols model