the temporal aspect of role performance.

$$f_{2}=\left\{\begin{array}{ll}h(lat\,e,\alpha)&\mbox{if}\,late>0\\ 0&\mbox{otherwise}\end{array}\right.\tag{13}$$

where late is the difference between the scheduled meeting time and the time the user arrives at the meeting room. late is probabilistically calculated by the MDP based on the user's current location and a model of the user's behavior.

$$f_{3}=\left\{\begin{array}{ll}r_{\alpha}+r_{uwr}&\mbox{if the user attends}\\ r_{\alpha}&\mbox{if the meeting takes place,but the user does not attend}\\ 0&\mbox{otherwise}\end{array}\right.\tag{14}$$

The value, r α , models the inherent value of α , while the value r u ser models the user's individual value to α .

f was given previously in Equation 11. The cost of communicating with the user depends on the medium which is used to communicate. For example, there is higher cost to communicating via a WAP phone than via a workstation dialog box.

When the users are asked for input, it is assumed that, if they respond, their response will be "correct", i.e., if a user says to delay the meeting by 15 minutes, we assume the user will arrive on time for the re-scheduled meeting. If the user is asked while in front of his/her workstation, a dialog like the one shown in Figure 5 is popped up, allowing the user to select the action to be taken. The expected quality of the agent's decision is calculated by considering the agent's proposed decision and the possible outcomes of that decision.

For example, if the agent proposes delaying the meeting by 15 minutes, the calculation of the decision quality includes the probability and benefits that the user will actually arrive 15 minutes after the originally scheduled meeting time, the probability and costs that the user arrives at the originally scheduled meeting time, etc.

![0_image_0.png](0_image_0.png)

The delay MDP also represents probabilities that a change in user location (e.g., from office to meeting location) will occur in a given time interval. Figure 5(b) shows a portion