panel regression ols gmm iv linear-models asset-pricing panel-data fixed-effects random-effects instrumental-variable statistical-model between-estimator first-difference clustered-standard-errors pooled-ols panel-models panel-regression seemingly-unrelated-regression fama-macbeth

machine-learning linear-regression regression estimation econometrics ols regression-models ols-regression fixed-effects clustered-standard-errors heteroskedasticity estimation-algorithm