If the specification test suggests unmeasured stable factors are important, difference-in-difference fixed effects estimators can provide unbiased impact estimates under some assumptions.
However, when shrinkage estimation procedures are used, transformations of the predictors can potentially impact estimates of effects and predictions.
Notes on chart sizing, from McKinsey Global Institute: These economic impact estimates are not comprehensive and include potential direct impact of sized applications only.
By quarter 10, impact estimates were nearly $200, implying about a 5percentt earnings increment.
Results presented in this paper are based on "intent-to-treat" impact estimates.
Step 2. The impact estimates were used to populate a spreadsheet.
However the dose, duration, and effectiveness of biological treatments significantly impact estimates of their cost-effectiveness.
Impact estimates could be inflated because a matched comparison group was used rather than random assignment, introducing unobserved selection bias.
Non-participation in the Employment Retention and Advancement Study: Implications for the experimental fourth-year impact estimates.. 2011.
If the program had little effect on nonparticipants, the impact estimates will understate the actual effects on the "treated" enrollees.
Figure 4 provides earnings impact estimates for the three states where ES recipients form the comparison group.
