Figure 5From: Evolving stochastic context-free grammars for RNA secondary structure predictionBrute force search. The distribution of sensitivity and corresponding PPV of grammars with at most 2 nonterminal variables. Approximately one quarter of grammars have sensitivity 0, as many cannot produce long strings. It is only the larger grammars that start to predict long strings which might correspond to structure. However, the prediction quality is still poor by both measures.Back to article page