For the lower branch, the evaluator is expected to produce:
These formulas can be verified by looking at the utility function in Section 4.5.1. To find a decision surface between the two alternatives, the points in the belief space at which the alternatives have equal utility are found. There is one solution in this case.
Therefore, it can be expected that the second agent will lend the car spanner when , and will lend the bike spanner when . Figure 4.4 is a plot of the planner's output, which conforms to expectations. This is the plot for which is identical to the plots for the other training levels, 2, 32 and 128.