code: def t_stat(Y):
      """Returns the t stat of the sample on each row of the matrix
  
      Parameters
      ----------
      Y, array of shape (n_samples, n_tests)
  
      Returns
      -------
      t_variates, array of shape (n_tests)
      """
      return Y.mean(0) / Y.std(0) * np.sqrt(Y.shape[0] - 1)
  
file_path: nipy/nipy/algorithms/statistics/mixed_effects_stat.py
imports: import numpy
label_desc: Use image node_id 3 for calling a global function with example usage: t_stat(Y) and returns: unknown