Cycle 1029 in figure 1b shows HAMB assigning low strengths to a task its heuristics suggest would not lead to a promising line of investigation.
HAMB selects a training set for inducing rules predicting crystal-form's values before doing so for other attributes primarily because crystal-form has the greatest a priori interest to the user but also because HAMB has discovered many good predictors of crystal-form.
HAMB creates the training set from the discovery database's examples that do not have uninformative values for crystal-form (for example, missing values, or "miscellaneous"), avoiding the induction of many uninteresting rules.
HAMB proposes the next step of inducing rules that predict crystal-form's values--selecting a feature set.
Because HAMB believes that it is harder to induce good rules using a small training set, HAMB assigns very low strengths to the reasons it provides for selecting a feature set for crystal-form, causing HAMB to postpone performing the newly proposed task until cycle 11,172.
When HAMB finally does induce a rule set for crystal-form, the accuracy of the induced role set on the testing database is 0.
This excerpt shows HAMB assigning low strengths to a task Its heuristics suggest would not lead to a promising line of investigation.
Cycle 1202 in figure 1c depicts HAMB beginning the process of inducing a rule set for a target attribute because it has found many reasons for doing so.
HAMB selects a training set for add-iron-[ii]-citrate before most of the attributes, not because it has a high estimated interestingness but because HAMB found many reasons for performing this task.
This excerpt depicts HAMB performing a task because it has determined that add-iron-[ii]-citrate might be an easy rule-induction target (not shown are the many reasons hamb found for doing so), not because add-iron-[ii]-citrate is especially interesting to the user.
HAMB'S ability to rediscover some of the patterns already known suggests that HAMB might be able to find equally useful patterns that are novel.
Other discoveries made by HAMB that increase our confidence in the results are its discovery of chemically reasonable patterns.