Rao,
Here are the common errors that the student made in doing
Homework 6. I’m typing up the answer sheet, will send you when finish.
1.1. Some student
found wrong plan with least number of action. Fewer mistakes in finding plan
with shortest plan (which involve more actions)
1.2. The common
mistake here are:
-
Do not explicitly say what happen at
each time point.
-
Assign the wrong time points for
achieving time of different fact.
-
Use one fuel level for all vehicles.
-
Mistake in checking the goal
satisfaction condition. Thus, only consider goals are satisfied when the state
subsumes the goals, instead of earlier time point where there are events that
achieve goals before goal deadlines.
2.1-2.2 Drawing the RTPG: many
students seemed to visualize the “real” plan when drawing the RTPG.
Thus, the actions are put in the RTPG at the wrong time point (later than it
should be). Therefore, wrong makespan values are
measured, which lead to wrong slack values too. Many made wrong cost value
measurement due to missing some actions when propagate the cost function.
Some students missed some critical actions, or place them at
the wrong time points.
2.3 Some people seem to “forget” this question and
did not list step-by-step how the relaxed plan can be found and simplified the
question by only listing the actions in the plan. Only Dan Bryce did it
right.
2.4 The common mistake here is to order actions without mutex relations as if it’s a real plan already (I
think the plans found in 1.1 influenced the answers for later questions).
Therefore, with mutex taken in, the plan looks the
same.
3 Common mistake is over concentrating
on the search strategy but not the expressiveness of the two planners.
Minh