1. Why the time a (p.3) was powered as time increases?
2. The author assumed the missing mechanism was caused by slope/intercept parameters, how can we interpret slope/intercept parameter in practical? Poor progress during high school?
3. The authors introduced the risk index in real data analysis and presented Figure 2. Why did it being omitted in simulation study as well as the group factor?
4. The y was substituted by estimate of theta score, it may be risky to ignore the standard error of theta.