How to Run Sentiment Analysis in Python using VADER

We have explained how to get a sentiment score for words in Python. Instead of building our own lexicon, we can use a pre-trained one like the VADER which stands from Valence Aware Dictionary and sEntiment Reasoner and is specifically attuned to sentiments expressed in social media. You can install the VADER library using pip like pip install vaderSentiment or you can get it directly from NTLK. You can have a look at VADER documentation. Notice that the pos, neu and neg probabilities add up to 1. Also, the compound score is a very useful metric in case we want a single measure of sentiment.