Task: Estimate the strength of emotion E in the tweet by assigning it a real-valued score between 0 and 1, where 0 signifies the least intensity and 1 signifies the greatest intensity.
Tweet: Why is it that we rejoice at a birth and grieve at a funeral? It is because we are not the person involved. ― Mark Twain
Emotion: sadness
Intensity score: 
0.354