fix a typo in ml_intro.md, tress -> trees
vector responses.
- Another optional component is the mask of missing measurements. Most algorithms require all the
components in all the training samples be valid, but some other algorithms, such as decision
- tress, can handle the cases of missing measurements.
+ trees, can handle the cases of missing measurements.
- In the case of classification problem user may want to give different weights to different
classes. This is useful, for example, when:
- user wants to shift prediction accuracy towards lower false-alarm rate or higher hit-rate.