Affordance Extraction with an External Knowledge Database for Text-Based Simulated Environments

The evaluation in the previous Section showed that external databases can be used to generate affordance for text based input with comparatively little effort. The results however have to be interpreted carefully to account for all upsides and limitations of this simple approach. For the automated evaluation (see Tables 1 and 2) three major observations have been made: The total amount and percentage of valid commands for the basic approach is rather low, yielding 52 commands (0.4%) for Jericho and 330 commands (6.4%) for TextWorld. This serves as an illustration point to the many potential challenges of automated affordance extraction. The amount of valid commands is increased by a factor of 2.9 (for Jericho) and 1.3 (for TextWorld), respectively, by manually adding trivial "take"- affordances to every evaluation step. This illustrates that information retrieved by external databases might often omit "trivial" information. The comparison between the results of Jericho and TextWorld showed a significant increase of the percentage of valid commands (by a factor of ca.