Description

Katie Leinenbach
1. Summary stats
Table 1 presents descriptive statistics for Medicare Part D Plans by Cohort from 2006 to 2010, a recreation of Table 1 in Ericson (2014).
2. Figure 3
Figure 1 presents the effect of the 2006 benchmark status on 2006 enrollment, a recreation of Figure 3 in Ericson (2014).
3. Figure 3
Figure 2 presents the effect of the 2006 benchmark status on 2006 enrollment with 10 bins instead of 20. Figure 3 presents the effect of the 2006 benchmark status on 2006 enrollment with 30 bins instead of 20. Changing the amount of bins does not change the trend. There is a jump in log enrollment share at the threshold, and the trends to the right and left of the threshold match in all three figures.
4. Evenly Spaced Optimal Bins
Figure 4 presents the effect of the 2006 benchmark status on 2006 enrollment with evenly spaced, optimal bins. This figure matches the figure from part 2 exactly, indicating that the optimal bins is 20.
5. Discrete Jump Test
Figure 5 shows that there is no statistical evidence of a manipulation of the running variable.
6. Recreate Table 3
Unfortunately I was unable to recreate Table 3.
7. CE Optimal Bandwidth
I do not understand how to apply the results from rdrobust to reestimate the RD results.
8. IV
Based on the regression, it appears that market share has a negative relationship with future premium changes. As a company has more market shares, they are less likely to change their premiums in the
future.
9. Comparison to Table 4
My values do not match the general trend found in Ericson (2014). I do not think I fully understand this assignment. I need to go back and reread this paper before attempting to complete the questions again.
10. Discussion
Tables and Figures
Table 1: Descriptive Statistics of Medicare Part D Plans
Cohort
2010
Mean monthly premium $37 $40 $36 $30 $33
(13) (17) (20) (5) (9)
Mean deductible $92 $114 $146 $253 $118
(116) (128) (125) (102) (139)
Fraction enhanced benefit 0.43 0.43 0.58 0.03
Fraction of plans offered by firms already offering a plan 0.69
….in the United States 0.00 0.76 0.98 1.00 0.97
….in the same state 0.00 0.53 0.91 0.68 0.86
Number of unique firms 51 38 16 5 6
Number of plans 1,429 658 202 68 107

Figure 1: Figure 3 Recreated

Figure 2: Figure 3 – 10 Bins

Figure 3: Figure 3 – 30 Bins

Figure 4: Figure 4 – Optimal Bins

Figure 5: Figure 5 – Jump Manipulation Test