l1id Native language identification shared task code repo NLI Track 1 Experiments <tr> <td>punctuation</td> <td>0.21</td> <td>0.20</td> <td>0.23</td> </tr> <tr> <td>punctuation+POS bigram</td> <td>0.31</td> <td>0.29</td> <td>0.33</td> </tr> Conditionavgminmax