For Grammar Error Correction task, why F0.5 is consider for evaluation and not F1? (Giving twice weight to precision than recall)

[Chayan Dhaddha]

For Grammar Error Correction task, why F0.5 is consider for evaluation and not F1? (Giving twice weight to precision than recall)

[vdobrovolskii]

You might want to check the CoNLL-2014 publication at https://aclanthology.org/W14-1701/
Section 4:

F0.5 emphasizes precision twice as much as recall, while F1 weighs precision and recall equally. When a grammar checker is put into actual use, it is important that its proposed corrections are highly accurate in order to gain user acceptance. Neglecting to propose a correction is not as bad as proposing an erroneous correction.