Time series model update (#278)

* updated lectures

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Co-authored-by: mmcky <[email protected]>
Co-authored-by: mmcky <[email protected]>
Co-authored-by: Trang Truong <[email protected]>
Co-authored-by: Jesse Perla <[email protected]>

Author: 4 people

lectures/continuous_time/covid_sde.md

@@ -624,4 +624,4 @@ In this case, there are significant differences between the early and late death
 
 This bleak simulation has assumed that no individuals has long-term immunity and that there will be no medical advancements on that time horizon - both of which are unlikely to be true.
 
-Nevertheless, it suggests that the timing of lifting lockdown has a more profound impact after 18 months if we allow stochastic shocks imperfect immunity.
+Nevertheless, it suggests that the timing of lifting lockdown has a more profound impact after 18 months if we allow stochastic shocks imperfect immunity.