I am trying to understand what the VADER does for analysis of sentences. Why is the hyper-parameter Alpha set to 15 here? I understand that the it is unstable when left unbound, but why 15?
def normalize(score, alpha=15):
"""
Normalize the score to be between -1 and 1 using an alpha that
approximates the max expected value
"""
norm_score = score/math.sqrt((score*score) + alpha)
return norm_score